renamed position_element() to layout_element()

thank you renderdoc for making me feel less stupid

.ecode/project_build.json

@@ -0,0 +1,43 @@
+{
+  "Debug": {
+    "build": [
+      {
+        "args": "-C resources/shaders",
+        "command": "make",
+        "working_dir": ""
+      },
+      {
+        "args": "build -g",
+        "command": "c3c",
+        "working_dir": ""
+      }
+    ],
+    "build_types": [],
+    "clean": [
+      {
+        "args": "clean",
+        "command": "c3c",
+        "working_dir": ""
+      }
+    ],
+    "config": {
+      "clear_sys_env": false
+    },
+    "os": [
+      "linux"
+    ],
+    "output_parser": {
+      "config": {
+        "relative_file_paths": true
+      }
+    },
+    "run": [
+      {
+        "args": "",
+        "command": "build/ugui",
+        "name": "Custom Executable",
+        "working_dir": ""
+      }
+    ]
+  }
+}

.gitignore

@@ -2,3 +2,7 @@
 *.a
 build/*
 **/.ccls-cache
+perf.data*
+*.rdc
+test_renderer
+resources/shaders/compiled/**

.gitmodules

@@ -1,3 +1,16 @@
-[submodule "lib/raylib.c3l"]
-	path = lib/raylib.c3l
-	url = https://github.com/NexushasTaken/raylib.c3l
+[submodule "lib/grapheme.c3l/thirdparty/libgrapheme"]
+	path = lib/grapheme.c3l/thirdparty/libgrapheme
+	url = git://git.suckless.org/libgrapheme
+	ignore = dirty
+[submodule "lib/schrift.c3l/thirdparty/libschrift"]
+	path = lib/schrift.c3l/thirdparty/libschrift
+	url = https://github.com/tomolt/libschrift
+	ignore = dirty
+[submodule "lib/sdl3.c3l"]
+	path = lib/sdl3.c3l
+	url = https://git.alemauri.eu/alema/sdl3.c3l
+	ignore = dirty
+[submodule "lib/vendor"]
+	path = lib/vendor
+	url = https://github.com/c3lang/vendor
+	ignore = dirty

Makefile

@@ -0,0 +1,3 @@
+test_renderer: test_renderer.c3 src/renderer.c3 resources/shaders/source/*
+	scripts/compile_shaders.sh
+	c3c compile -g -O0 test_renderer.c3 src/renderer.c3 --libdir lib --lib sdl3 --lib ugui

TODO

@@ -1,32 +1,127 @@
 # TODOs, semi-random sorting
+
 [x] Implement glyph draw command
 [x] Implement div.view and scrollbars
-[ ] Port font system from C to C3 (rewrite1)
+[x] Port font system from C to C3 (rewrite1)
 [ ] Update ARCHITECTURE.md
 [ ] Write a README.md
 [ ] Use an arena allocator for cache
 [ ] Do not redraw if there was no update (no layout and no draw)
-[ ] Better handling of the active and focused widgets, try
-    to maintain focus until mouse release (fix scroll bars)
+[ ] Do command buffer damage tracking based on a context grid (see rxi writeup)
+[x] Better handling of the active and focused widgets, try
+to maintain focus until mouse release (fix scroll bars)
+[x] Clip element bounds to parent div, specifically text
+[ ] Resizeable divs
+[x] Implement a z index and sort command buffer based on that
+    [ ] Ctx.set_z_index()
+    [x] Sort command buffer on insertion
+[x] Standardize element handling, for example all buttons do almost the same thing, so write a lot 
+    of boiler plate and reuse it
+[x] The id combination in gen_id() uses an intger division, which is costly, use another combination 
+    function that is non-linear and doesn't use division
+[ ] Animations, somehow
+[x] Maybe cache codepoint converted strings
+[x] Fix scroll wheel when div is scrolled
+[ ] Be consistent with the initialization methods some are foo.new() and some are foo.init()
+[ ] Implement image loading (.bmp, .ff, .qoi and .png), in the future even lossy images like .jpg
+    [x] .qoi
+    [ ] .ff
+    [ ] .bmp
+    [ ] .png
+    [ ] .jpg
+[ ] gif support?
+[ ] layout_set_max_rows() and layout_set_max_columns()
+[x] Maybe SDF sprites??
+[x] Stylesheets and stylesheet import
+[x] use SDF to draw anti-aliased rounded rectangles https://zed.dev/blog/videogame
+[ ] Subdivide modules into ugui::ug for exported functions and ugui::core for
+    internal use functions (used to create widgets)
+[x] The render loop RAPES the gpu, valve pls fix
+[ ] The way the element structures are implemented wastes a lot of memory since
+    each struct Elem, struct Cmd, etc. is as big as the largest element. It would
+    be better to use a different allcation strategy.
+[ ] Add a way to handle time events like double clicks
+[x] Fix how padding is applied in push_rect. In CSS padding is applied between the border and the
+    content, the background color is applied starting from the border. Right now push_rect() offsets
+    the background rect by both border and padding
+[ ] Investigate why the debug pointer (cyan rectangle) disappears... 
+
+## Layout
+
+[x] Flexbox
+[ ] Center elements to the row/column
+[x] Text wrapping / reflow
+[x] Implement a better and unified way to place a glyph and get the cursor position, maybe with a struct
+[ ] Correct whitespace handling in text (\t \r etc)
+[ ] Consider a multi-pass recursive approach to layout (like https://github.com/nicbarker/clay)
+    instead of the curren multi-frame approach.
+[ ] Implement column/row sizing (min, max)
+[ ] Find a way to concile pixel measurements to the mm ones used in css, for example in min/max sizing
+    of elements
+[ ] Center elements to div (center children_bounds to the center of the div bounds and shift the origin accordingly)
+[x] Use containing_rect() in position_element() to skip some computing and semplify the function
+[x] Rename position_element() to layout_element()
+[ ] Make functions to mark rows/columns as full, to fix the calculator demo
+
+## Input
+
+[x] Keyboard input
+[x] Mouse scroll wheel
+[ ] Touch input
+[x] Do not set input event to true if the movement was zero (like no mouse movement)
+[ ] Use input event flags, for example to consume the input event
+[ ] Fix bug in text box: when spamming keys you can get multiple characters in the text input field
+    of the context, this causes a bug where only the first char is actually used
 
 ## Commands
-[x] rect commads should have:
-	* border width
-	* border radius
-[x] add a command to update an atlas
 
-## Atlases
+[x] rect commads should have:
+    - border width
+    - border radius
+[x] add a command to update an atlas
+[ ] New window command, useful for popups
+[x] Text command returns the text bounds, this way we can avoid the pattern 
+    draw_text(a, pos) -> off = compute_bounds(a) -> draw_text(b, pos+off) -> ...
+[ ] Rounded rectangle with different radius for each corner
+
+## Atlas
+
 [ ] Add an interface to create, destroy, update and get atlases based on their ids
 [ ] Implement multiple font atlases
+[ ] Pixel format conversion
 
 ## Fonts
-[ ] Fix the missing alpha channel
+
+[x] Fix the missing alpha channel
 [x] Fix the alignment
 
-## Raylib
-[ ] Implement type (Rect, Color, Point) conversion functions between rl:: and ugui::
-[x] Implement pixel radius rounding for border radius
-
 ## Widgets
-[ ] Dynamic text box to implement an fps counter
-[ ] Button with label
+
+[x] Dynamic text box to implement an fps counter
+[x] Button with label
+[x] Text Input box
+[ ] Icon Buttons
+[x] Switch
+[x] Checkbox
+[ ] Selectable text box
+
+## API
+
+[ ] Introduce a Layout structure that specifies the positioning of elements inside
+    a Div element. This would allow specifying alignment, maximum and minimum sizing
+    margins between children, etc.
+    This is different from style which is applied per-element.
+[ ] Remove Ids for element that don't need them. Such elements are button, toggles,
+    and all elements which do not have internal data that has to be cached and/or
+    queried by the user for later use. This allows for smaller caches and in general
+    reduces some load, since most of the stuff is recomputed for every frame.
+
+## SDL3 Renderer
+
+[x] smart batching
+[x] maybe use instancing since we are always drawing the same geometry. With instancing every
+    different quad could have its coulour, border and radius with much better performance than
+    issuing a draw call for every quad (and uploading it)
+    https://rastertek.com/dx11win10tut48.html
+    https://www.braynzarsoft.net/viewtutorial/q16390-33-instancing-with-indexed-primitives
+[ ] implement min and max fps

lib/grapheme.c3l/Makefile

@@ -1,3 +1,4 @@
 all:
 	make -C thirdparty/libgrapheme
+	mkdir -p linux-x64
 	cp thirdparty/libgrapheme/libgrapheme.a linux-x64/libgrapheme.a

lib/grapheme.c3l/project.json

@@ -0,0 +1,14 @@
+{
+  "langrev": "1",
+  "warnings": ["no-unused"],
+  "dependency-search-paths": [".."],
+  "dependencies": ["grapheme"],
+  "authors": ["Alessandro Mauri <alemauri001@gmail.com>", "Laslo Hunhold <dev@frign.de>"],
+  "version": "0.1.0",
+  "sources": [],
+  "output": "build",
+  "target": "linux-x64",
+  "features": [],
+  "cpu": "generic",
+  "opt": "O0"
+}

lib/libgrapheme.c3l/project.json

@@ -1,44 +0,0 @@
-{
-  // Language version of C3.
-  "langrev": "1",
-  // Warnings used for all targets.
-  "warnings": ["no-unused"],
-  // Directories where C3 library files may be found.
-  "dependency-search-paths": [".."],
-  // Libraries to use for all targets.
-  "dependencies": ["grapheme"],
-  // Authors, optionally with email.
-  "authors": ["Alessandro Mauri <alemauri001@gmail.com"],
-  // Version using semantic versioning.
-  "version": "0.1.0",
-  // Sources compiled for all targets.
-  "sources": [],
-  // C sources if the project also compiles C sources
-  // relative to the project file.
-  // "c-sources": [ "csource/**" ],
-  // Output location, relative to project file.
-  "output": "build",
-  // Architecture and OS target.
-  // You can use 'c3c --list-targets' to list all valid targets.
-  // "target": "windows-x64",
-  "features": [
-    // See rcore.c3
-    //"SUPPORT_INTERNAL_MEMORY_MANAGEMENT",
-    //"SUPPORT_STANDARD_FILEIO",
-    //"SUPPORT_FILE_SYSTEM_FUNCTIONS",
-    //"SUPPORT_DATA_ENCODER",
-    // See text.c3
-    //"SUPPORT_TEXT_CODEPOINTS_MANAGEMENT",
-    //"SUPPORT_TEXT_C_STRING_MANAGEMENT",
-    //"SUPPORT_RANDOM_GENERATION",
-    //"SUPPORT_RAYGUI",
-    //"RAYGUI_NO_ICONS",
-    //"RAYGUI_CUSTOM_ICONS",
-  ],
-  // Global settings.
-  // CPU name, used for optimizations in the LLVM backend.
-  "cpu": "generic",
-  // Optimization: "O0", "O1", "O2", "O3", "O4", "O5", "Os", "Oz".
-  "opt": "O0"
-  // See resources/examples/project_all_settings.json and 'c3c --list-project-properties' to see more properties.
-}

lib/libschrift.c3l/project.json

@@ -1,45 +0,0 @@
-{
-  // Language version of C3.
-  "langrev": "1",
-  // Warnings used for all targets.
-  "warnings": [ "no-unused" ],
-  // Directories where C3 library files may be found.
-  "dependency-search-paths": [ ".." ],
-  // Libraries to use for all targets.
-  "dependencies": [ "schrift" ],
-  // Authors, optionally with email.
-  "authors": [ "Alessandro Mauri <alemauri001@gmail.com" ],
-  // Version using semantic versioning.
-  "version": "0.1.0",
-  // Sources compiled for all targets.
-  "sources": [ ],
-  // C sources if the project also compiles C sources
-  // relative to the project file.
-  // "c-sources": [ "csource/**" ],
-  // Output location, relative to project file.
-  "output": "build",
-  // Architecture and OS target.
-  // You can use 'c3c --list-targets' to list all valid targets.
-  // "target": "windows-x64",
-  "features": [
-    // See rcore.c3
-    //"SUPPORT_INTERNAL_MEMORY_MANAGEMENT",
-    //"SUPPORT_STANDARD_FILEIO",
-    //"SUPPORT_FILE_SYSTEM_FUNCTIONS",
-    //"SUPPORT_DATA_ENCODER",
-    // See text.c3
-    //"SUPPORT_TEXT_CODEPOINTS_MANAGEMENT",
-    //"SUPPORT_TEXT_C_STRING_MANAGEMENT",
-    //"SUPPORT_RANDOM_GENERATION",
-
-    //"SUPPORT_RAYGUI",
-    //"RAYGUI_NO_ICONS",
-    //"RAYGUI_CUSTOM_ICONS",
-  ],
-  // Global settings.
-  // CPU name, used for optimizations in the LLVM backend.
-  "cpu": "generic",
-  // Optimization: "O0", "O1", "O2", "O3", "O4", "O5", "Os", "Oz".
-  "opt": "O0",
-  // See resources/examples/project_all_settings.json and 'c3c --list-project-properties' to see more properties.
-}

lib/raylib.c3l

@@ -1 +0,0 @@
-Subproject commit c7ebe054ce16136c1128fab54fcce4921044293e

lib/schrift.c3l/Makefile

@@ -1,3 +1,4 @@
 all:
 	make -C thirdparty/libschrift
+	mkdir -p linux-x64
 	cp thirdparty/libschrift/libschrift.a linux-x64/libschrift.a

lib/schrift.c3l/libschrift.c3

@@ -1,8 +1,8 @@
 module schrift;
 
-def SftFont = void*;
-def SftUChar = uint;
-def SftGlyph = uint;
+alias SftFont  = void*;
+alias SftUChar = uint;
+alias SftGlyph = uint;
 
 const int SFT_DOWNWARD_Y = 0x01;
 
@@ -45,10 +45,10 @@ struct SftImage
 	int   height;
 }
 
-extern fn char* sft_version() @extern("sft_version");
+extern fn ZString sft_version() @extern("sft_version");
 
 extern fn SftFont loadmem(void* mem, usz size) @extern("sft_loadmem");
-extern fn SftFont loadfile(char* filename) @extern("sft_loadfile");
+extern fn SftFont loadfile(ZString filename) @extern("sft_loadfile");
 extern fn void freefont(SftFont font) @extern("sft_freefont");
 
 extern fn int lmetrics(Sft* sft, SftLMetrics* metrics) @extern("sft_lmetrics");

lib/schrift.c3l/project.json

@@ -0,0 +1,14 @@
+{
+  "langrev": "1",
+  "warnings": [ "no-unused" ],
+  "dependency-search-paths": [ ".." ],
+  "dependencies": [ "schrift" ],
+  "authors": [ "Alessandro Mauri <alemauri001@gmail.com>", "Thomas Oltmann <thomas.oltmann.hhg@gmail.com>" ],
+  "version": "0.1.0",
+  "sources": [ ],
+  "output": "build",
+  "target": "linux-x64",
+  "features": [],
+  "cpu": "generic",
+  "opt": "O0",
+}

lib/sdl3.c3l

@@ -0,0 +1 @@
+Subproject commit 076355e2d126e7546e53663b97e8dec22667d34d

lib/ugui.c3l/README.md

@@ -0,0 +1 @@
+Welcome to the ugui library.

lib/ugui.c3l/manifest.json

@@ -0,0 +1,11 @@
+{
+  "provides" : "ugui",
+  "sources" : [ "src/**" ],
+  "targets" : {
+    "linux-x64" : {
+      "link-args" : [],
+      "dependencies" : ["schrift", "grapheme"],
+      "linked-libraries" : []
+    }
+  }
+}

lib/ugui.c3l/src/cache.c3

@@ -1,4 +1,4 @@
-module cache(<Key, Value, SIZE>);
+module cache{Key, Value, SIZE};
 
 /* LRU Cache
  * The cache uses a pool (array) to store all the elements, each element has
@@ -14,12 +14,13 @@ module cache(<Key, Value, SIZE>);
 //        happens at the same time
 
 import std::core::mem;
+import std::core::mem::allocator;
 import std::collections::bitset;
 import std::collections::map;
 
-def BitArr = bitset::BitSet(<SIZE>) @private;
-def IdTable = map::HashMap(<Key, usz>) @private;
-def IdTableEntry = map::Entry(<Key, usz>) @private;
+alias BitArr = bitset::BitSet{SIZE};
+alias IdTable = map::HashMap{Key, usz};
+alias IdTableEntry = map::Entry{Key, usz};
 
 const usz CACHE_NCYCLES = (usz)(SIZE * 2.0/3.0);
 
@@ -42,9 +43,9 @@ macro Cache.cycle(&cache) @private {
 	}
 }
 
-fn void! Cache.init(&cache)
+fn void? Cache.init(&cache)
 {
-	cache.table.new_init(capacity: SIZE);
+	cache.table.init(allocator::heap(), capacity: SIZE);
 	// FIXME: this shit is SLOW
 	foreach (idx, bit : cache.used) { cache.used[idx] = false; }
 	foreach (idx, bit : cache.present) { cache.present[idx] = false; }
@@ -57,21 +58,22 @@ fn void Cache.free(&cache)
 	(void)mem::free(cache.pool);
 }
 
-fn Value*! Cache.search(&cache, Key id)
+fn Value*? Cache.search(&cache, Key id)
 {
 	// get_entry() faults on miss
 	IdTableEntry* entry = cache.table.get_entry(id)!;
 
-	/* MISS */
+	/* MISS, wrong key */
 	if (entry.key != id) {
-		return SearchResult.MISSING?;
+		cache.table.remove(id)!;
+		return NOT_FOUND?;
 	}
 
 	/* MISS, the data is not valid (not present) */
 	if (!cache.present[entry.value]) {
 		// if the data is not present but it is still in the table, remove it
 		cache.table.remove(id)!;
-		return SearchResult.MISSING?;
+		return NOT_FOUND?;
 	}
 
 	/* HIT, set as recently used */
@@ -79,6 +81,18 @@ fn Value*! Cache.search(&cache, Key id)
 	return &(cache.pool[entry.value]);
 }
 
+fn void Cache.remove(&cache, Key id)
+{
+	IdTableEntry*? entry = cache.table.get_entry(id);
+	if (catch entry) {
+		return;
+	}
+
+	// found, remove it
+	cache.present[entry.value] = false;
+	(void)cache.table.remove(id);
+}
+
 /* Look for a free spot in the present bitmap and return its index */
 /* If there is no free space left then just return the first position */
 fn usz Cache.get_free_spot(&cache) @private
@@ -92,7 +106,7 @@ fn usz Cache.get_free_spot(&cache) @private
 	return 0;
 }
 
-fn Value*! Cache.insert_at(&cache, Value *g, Key id, usz index) @private
+fn Value*? Cache.insert_at(&cache, Value *g, Key id, usz index) @private
 {
 	// TODO: verify index, g and id
 	Value* spot;
@@ -109,17 +123,17 @@ fn Value*! Cache.insert_at(&cache, Value *g, Key id, usz index) @private
 }
 
 // Insert an element in the cache, returns the index
-fn Value*! Cache.insert_new(&cache, Value* g, Key id)
+fn Value*? Cache.insert_new(&cache, Value* g, Key id)
 {
 	usz index = cache.get_free_spot();
 	return cache.insert_at(g, id, index);
 }
 
-fn Value*! Cache.get_or_insert(&cache, Value* g, Key id, bool *is_new = null)
+fn Value*? Cache.get_or_insert(&cache, Value* g, Key id, bool *is_new = null)
 {
-	Value*! c = cache.search(id);
+	Value*? c = cache.search(id);
 	if (catch e = c) {
-		if (e != SearchResult.MISSING) {
+		if (e != NOT_FOUND) {
 			return e?;
 		} else {
 			// if the element is new (inserted) set the is_new flag

lib/ugui.c3l/src/fifo.c3

@@ -0,0 +1,91 @@
+module fifo::faults;
+faultdef FULL, EMPTY;
+
+module fifo{Type};
+
+import std::core::mem;
+import std::sort;
+
+// TODO: specify the allocator
+
+struct Fifo {
+	Type[] arr;
+	usz out;
+	usz count;
+}
+
+fn void? Fifo.init(&fifo, usz size)
+{
+	fifo.arr = mem::new_array(Type, size);
+	fifo.out = 0;
+	fifo.count = 0;
+}
+
+fn void Fifo.free(&fifo)
+{
+	(void)mem::free(fifo.arr);
+}
+
+fn void? Fifo.enqueue(&fifo, Type *elem)
+{
+	if (fifo.count >= fifo.arr.len) {
+		return fifo::faults::FULL?;
+	}
+	usz in = (fifo.out + fifo.count) % fifo.arr.len;
+	fifo.arr[in] = *elem;
+	fifo.count++;
+}
+
+fn Type*? Fifo.dequeue(&fifo)
+{
+	if (fifo.count == 0) {
+		return fifo::faults::EMPTY?;
+	}
+	Type *ret = &fifo.arr[fifo.out];
+	fifo.count--;
+	fifo.out = (fifo.out + 1) % fifo.arr.len;
+	return ret;
+}
+
+macro Type Fifo.get(&fifo, usz i) @operator([])
+{
+	return fifo.arr[(fifo.out + i) % fifo.arr.len];
+}
+
+fn void Fifo.set(&fifo, usz i, Type val) @operator([]=)
+{
+	fifo.arr[(fifo.out + i) % fifo.arr.len] = val;
+}
+
+macro Type* Fifo.get_ref(&fifo, usz i) @operator(&[])
+{
+	return &fifo.arr[(fifo.out + i) % fifo.arr.len];
+}
+
+macro usz Fifo.len(&fifo) @operator(len)
+{
+	return fifo.count;
+}
+
+fn void? Fifo.sort(&fifo)
+{
+	Type[] arr = mem::new_array(Type, fifo.count);
+	defer mem::free(arr);
+
+	foreach(i, c: fifo) {
+		arr[i] = c;
+	}
+
+	// doesn't keep ordering
+	//sort::quicksort(arr);
+
+	// seems to keep the right order but we will never know...
+	// also since most things are already ordered the time is closer to O(n) than to O(n^2)
+	sort::insertionsort(arr);
+
+	fifo.count = 0;
+	fifo.out = 0;
+	foreach (&c: arr) {
+		fifo.enqueue(c)!;
+	}
+}

lib/ugui.c3l/src/ugui_atlas.c3

@@ -0,0 +1,131 @@
+module ugui;
+
+import std::io;
+
+faultdef CANNOT_PLACE, INVALID_TYPE;
+
+enum AtlasType {
+	ATLAS_GRAYSCALE,
+	ATLAS_R8G8B8A8,
+}
+
+// black and white atlas
+struct Atlas {
+	AtlasType type;
+	Id id;
+
+	ushort width, height;
+	char[] buffer;
+
+	Point row;
+	ushort row_h;
+}
+
+// bytes per pixel
+macro usz AtlasType.bpp(type)
+{
+	switch (type) {
+	case ATLAS_GRAYSCALE: return 1;
+	case ATLAS_R8G8B8A8: return 4;
+	}
+}
+
+macro typeid AtlasType.underlying(type)
+{
+	switch (type) {
+	case ATLAS_GRAYSCALE: return char;
+	case ATLAS_R8G8B8A8: return uint;
+	}
+}
+
+/*
+// FIXME: in and out types are not always known at compile time
+macro @pixel_convert(p, AtlasType $in, AtlasType $out)
+{
+	$if $in == $out:
+		return p;
+	$else
+		$switch
+		$case $in == ATLAS_R8G8B8A8 && $out == ATLAS_GRAYSCALE:
+			var r = ((p >> 0)  & 0xff);
+			var g = ((p >> 8)  & 0xff);
+			var b = ((p >> 16) & 0xff);
+			var a = ((p >> 24) & 0xff);
+			if (a == 0)	return (char)0;
+			return (ATLAS_GRAYSCALE.underlying())(((float)r+g+b) / 3.0f);
+		$case $in == ATLAS_GRAYSCALE && $out == ATLAS_R8G8B8A8:
+			var x = (char)(p/3.0);
+			return (ATLAS_R8G8B8A8.underlying())(x|(x<<8)|(x<<16)|(255<<24));
+		$default: $error "Unimplemented pixel format conversion";
+		$endswitch
+	$endif
+}
+*/
+
+fn void? Atlas.new(&atlas, Id id, AtlasType type, ushort width, ushort height)
+{
+	atlas.id = id;
+	atlas.type = type;
+	atlas.width = width;
+	atlas.height = height;
+
+	atlas.buffer = mem::new_array(char, (usz)atlas.width*atlas.height*type.bpp());
+}
+
+fn void Atlas.free(&atlas)
+{
+	free(atlas.buffer);
+}
+
+
+/*
+ * pixels -> +--------------+-----+
+ *           |              |     | h
+ *           |              |     | e
+ *           |              |     | i
+ *           |              |     | g
+ *           |              |     | h
+ *           |              |     | t
+ *           +--------------+-----+
+ *           |<--- width -->|
+ *           |<----- stride ----->|
+ * bytes per pixels are inferred and have to be the same
+ * as the atlas type
+ */
+// place a rect inside the atlas
+// uses a row first algorithm
+// TODO: use a skyline algorithm https://jvernay.fr/en/blog/skyline-2d-packer/implementation/
+fn Point? Atlas.place(&atlas, char[] pixels, ushort w, ushort h, ushort stride)
+{
+	Point p;
+
+	if (atlas.row.x + w <= atlas.width && atlas.row.y + h <= atlas.height) {
+		p = atlas.row;
+	} else {
+		atlas.row.x = 0;
+		atlas.row.y = atlas.row.y + atlas.row_h;
+		atlas.row_h = 0;
+		if (atlas.row.x + w <= atlas.width && atlas.row.y + h <= atlas.height) {
+			p = atlas.row;
+		} else {
+			return CANNOT_PLACE?;
+		}
+	}
+
+	usz bpp = atlas.type.bpp();
+	for (usz y = 0; y < h; y++) {
+		for (usz x = 0; x < w; x++) {
+			char[] buf = atlas.buffer[(usz)(p.y+y)*atlas.width*bpp + (p.x+x)*bpp ..];
+			char[] pix = pixels[(usz)y*stride*bpp + x*bpp ..];
+
+			buf[0..bpp-1] = pix[0..bpp-1];
+		}
+	}
+
+	atlas.row.x += w;
+	if (h > atlas.row_h) {
+		atlas.row_h = h;
+	}
+
+	return p;
+}

lib/ugui.c3l/src/ugui_button.c3

@@ -0,0 +1,153 @@
+module ugui;
+
+import std::io;
+
+// button element
+struct ElemButton {
+	int filler;
+}
+
+
+macro Ctx.button(&ctx, String label = "", String icon = "", ...)
+	=> ctx.button_id(@compute_id($vasplat), label, icon);
+fn ElemEvents? Ctx.button_id(&ctx, Id id, String label, String icon)
+{
+	id = ctx.gen_id(id)!;
+	Elem *parent = ctx.get_parent()!;
+	Elem *elem = ctx.get_elem(id, ETYPE_BUTTON)!;
+	Style* style = ctx.styles.get_style(@str_hash("button"));
+	
+	Sprite* sprite = icon != "" ? ctx.sprite_atlas.get(icon)! : &&(Sprite){};
+
+	Rect min_size = {0, 0, style.size, style.size};
+	Rect text_size = ctx.get_text_bounds(label)!;
+	Rect icon_size = sprite.rect();
+
+	ushort h_lh = (ushort)(ctx.font.line_height() / 2);
+	ushort left_pad = label != "" ? h_lh : 0;
+	ushort inner_pad = label != "" && icon != "" ? h_lh : 0;
+	ushort right_pad = left_pad;
+	
+	/*    |left_pad
+	 * +--v-----------------------------------+
+	 * |<->+--------+                         |
+	 * |   |        |   +-----------------+   |
+	 * |   |  icon  |   |     label       |   |
+	 * |   |        |   +-----------------+   |
+	 * |   +--------+<->|                 |<->|
+	 * +-------------^--------------------^---+
+	 *               |inner_pad           |right_pad
+	 */
+	
+	Rect tot_size = {
+		.w = (short)max(min_size.w, icon_size.w + text_size.w + left_pad + inner_pad + right_pad),
+		.h = (short)max(min_size.h, max(icon_size.h, text_size.h)),
+	};
+	
+	elem.bounds = ctx.layout_element(parent, tot_size, style);
+	if (elem.bounds.is_null()) return {};
+	elem.events = ctx.get_elem_events(elem);
+	Rect content_bounds = elem.content_bounds(style);
+	
+	Rect text_bounds = {
+		.x = content_bounds.x + icon_size.w + left_pad + inner_pad,
+		.y = content_bounds.y,
+		.w = content_bounds.w - icon_size.w - left_pad - inner_pad - right_pad,
+		.h = content_bounds.h
+	};
+	text_bounds = text_size.center_to(text_bounds);
+	
+	Rect icon_bounds = {
+		.x = content_bounds.x,
+		.y = content_bounds.y,
+		.w = icon_size.w + right_pad + inner_pad,
+		.h = (short)max(icon_size.h, content_bounds.h)
+	};
+	icon_bounds = icon_size.center_to(icon_bounds);
+	
+	bool is_active = ctx.elem_focus(elem) || elem.events.mouse_hover;
+	Style s = *style;
+	if (is_active) {
+		s.secondary = s.primary;
+		s.bg = s.accent;
+	}
+
+	ctx.push_rect(elem.bounds, parent.div.z_index, &s)!;
+	ctx.push_sprite(icon_bounds, sprite.uv(), ctx.sprite_atlas.id, parent.div.z_index, type: sprite.type)!;
+//	Style ss = {.bg = 0x000000ffu.@to_rgba()};
+//	ctx.push_rect(content_bounds, parent.div.z_index, &ss)!;
+	ctx.push_string(text_bounds, label, parent.div.z_index, style.fg)!;
+	
+	return elem.events;
+}
+
+
+// FIXME: this should be inside the style
+macro Ctx.checkbox(&ctx, String desc, Point off, bool* active, String tick_sprite = {}, ...)
+	=> ctx.checkbox_id(@compute_id($vasplat), desc, off, active, tick_sprite);
+fn void? Ctx.checkbox_id(&ctx, Id id, String description, Point off, bool* active, String tick_sprite)
+{
+	id = ctx.gen_id(id)!;
+
+	Elem *parent = ctx.get_parent()!;
+	Elem *elem = ctx.get_elem(id, ETYPE_BUTTON)!;
+	Style* style = ctx.styles.get_style(@str_hash("checkbox"));
+
+	Rect size = {off.x, off.y, style.size, style.size};
+	elem.bounds = ctx.layout_element(parent, size, style);
+
+	// if the bounds are null the element is outside the div view,
+	//  no interaction should occur so just return
+	if (elem.bounds.is_null()) return;
+
+	elem.events = ctx.get_elem_events(elem);
+	if (elem.events.mouse_hover && elem.events.mouse_release) *active = !(*active);
+	
+	if (tick_sprite != {}) {
+		ctx.push_rect(elem.bounds, parent.div.z_index, style)!;
+		if (*active) {
+			ctx.draw_sprite_raw(tick_sprite, elem.bounds, center: true)!;
+		}
+	} else {
+		ctx.push_rect(elem.bounds, parent.div.z_index, style)!;
+		if (*active) {
+			ushort x = style.size / 4;
+			Rect check = elem.bounds.add({x, x, -x*2, -x*2});
+			Style s = *style;
+			s.bg = s.primary;
+			s.margin = s.border = s.padding = {};
+			ctx.push_rect(check, parent.div.z_index, &s)!;
+		}
+	}
+}
+
+// FIXME: this should be inside the style
+macro Ctx.toggle(&ctx, String desc, Point off, bool* active)
+	=> ctx.toggle_id(@compute_id($vasplat), desc, off, active);
+fn void? Ctx.toggle_id(&ctx, Id id, String description, Point off, bool* active)
+{
+	id = ctx.gen_id(id)!;
+
+	Elem *parent = ctx.get_parent()!;
+	Elem *elem = ctx.get_elem(id, ETYPE_BUTTON)!;
+	Style* style = ctx.styles.get_style(@str_hash("toggle"));
+
+	Rect size = {off.x, off.y, style.size*2, style.size};
+	elem.bounds = ctx.layout_element(parent, size, style);
+
+	// if the bounds are null the element is outside the div view,
+	//  no interaction should occur so just return
+	if (elem.bounds.is_null()) return;
+
+	elem.events = ctx.get_elem_events(elem);
+	if (elem.events.mouse_hover && elem.events.mouse_release) *active = !(*active);
+
+	// Draw the button
+	// FIXME: THIS IS SHIT
+	ctx.push_rect(elem.bounds, parent.div.z_index, style)!;
+	Rect t = elem.bounds.add({*active ? (style.size+3) : +3, +3, -style.size-6, -6});
+	Style s = *style;
+	s.bg = s.primary;
+	s.margin = s.border = s.padding = {};
+	ctx.push_rect(t, parent.div.z_index, &s)!;
+}

lib/ugui.c3l/src/ugui_cmd.c3

@@ -0,0 +1,181 @@
+module ugui;
+
+import std::ascii;
+import std::io;
+
+// command type
+enum CmdType {
+	CMD_RECT,
+	CMD_UPDATE_ATLAS,
+	CMD_SPRITE,
+	CMD_SCISSOR,
+}
+
+// command to draw a rect
+struct CmdRect {
+	Rect rect;
+	ushort radius;
+	Color color;
+}
+
+struct CmdUpdateAtlas {
+	Id id;
+	char* raw_buffer;
+	short width, height, bpp;
+}
+
+struct CmdSprite {
+	Id texture_id;
+	SpriteType type;
+	Rect rect;
+	Rect texture_rect;
+	Color hue;
+}
+
+// if rect is zero Rect{0} then reset the scissor
+struct CmdScissor {
+	Rect rect;
+}
+
+// command structure
+struct Cmd (Printable) {
+	CmdType type;
+	int z_index; 
+	union {
+		CmdRect rect;
+		CmdUpdateAtlas update_atlas;
+		CmdSprite sprite;
+		CmdScissor scissor;
+	}
+}
+
+fn int Cmd.compare_to(Cmd a, Cmd b)
+{
+	if (a.z_index == b.z_index) return 0;
+	return a.z_index > b.z_index ? 1 : -1;
+}
+
+// implement the Printable interface
+fn usz? Cmd.to_format(Cmd* cmd, Formatter *f) @dynamic
+{
+	return f.printf("Cmd{ type: %s, z_index: %d }", cmd.type, cmd.z_index);
+}
+
+macro bool cull_rect(Rect rect, Rect clip = {0,0,short.max,short.max})
+{
+	bool no_area = rect.w <= 0 || rect.h <= 0;
+	return no_area || !rect.collides(clip);
+}
+
+// FIXME: this whole thing could be done at compile time, maybe
+macro Ctx.push_cmd(&ctx, Cmd *cmd, int z_index)
+{
+	cmd.z_index = z_index;
+	Rect rect;
+	switch (cmd.type) {
+	case CMD_RECT: rect = cmd.rect.rect;
+	case CMD_SPRITE: rect = cmd.sprite.rect;
+	default: return ctx.cmd_queue.enqueue(cmd);
+	}
+	if (cull_rect(rect, ctx.div_scissor)) return;
+	return ctx.cmd_queue.enqueue(cmd);
+}
+
+fn void? Ctx.push_scissor(&ctx, Rect rect, int z_index)
+{
+	Cmd sc = {
+		.type = CMD_SCISSOR,
+		.scissor.rect = rect.intersection(ctx.div_scissor),
+	};
+	ctx.push_cmd(&sc, z_index)!;
+}
+
+fn void? Ctx.push_rect(&ctx, Rect rect, int z_index, Style* style)
+{
+	Rect border        = style.border;
+	ushort radius      = style.radius;
+	Color bg           = style.bg;
+	Color border_color = style.secondary;
+
+	// FIXME: this implies that the border has to be uniform
+	if (!border.is_null()) {
+		Cmd cmd = {
+			.type = CMD_RECT,
+			.rect.rect = rect,
+			.rect.color = border_color,
+			.rect.radius = radius + border.x,
+		};
+		ctx.push_cmd(&cmd, z_index)!;
+	}
+
+	Cmd cmd = {
+		.type = CMD_RECT,
+		.rect.rect = {
+			.x = rect.x + border.x,
+			.y = rect.y + border.y,
+			.w = rect.w - (border.x+border.w),
+			.h = rect.h - (border.y+border.h),
+		},
+		.rect.color = bg,
+		.rect.radius = radius,
+	};
+	if (cull_rect(cmd.rect.rect, ctx.div_scissor)) return;
+	ctx.push_cmd(&cmd, z_index)!;
+}
+
+// TODO: accept a Sprite* instead of all this shit
+fn void? Ctx.push_sprite(&ctx, Rect bounds, Rect texture, Id texture_id, int z_index, Color hue = 0xffffffffu.to_rgba(), SpriteType type = SPRITE_NORMAL)
+{
+	Cmd cmd = {
+		.type = CMD_SPRITE,
+		.sprite.type = type,
+		.sprite.rect = bounds,
+		.sprite.texture_rect = texture,
+		.sprite.texture_id = texture_id,
+		.sprite.hue = hue,
+	};
+	ctx.push_cmd(&cmd, z_index)!;
+}
+
+// TODO: do not return the WHOLE TextInfo but instead something smaller
+fn TextInfo? Ctx.push_string(&ctx, Rect bounds, char[] text, int z_index, Color hue, bool reflow = false)
+{
+	if (text.len == 0) {
+		return {};
+	}
+
+	ctx.push_scissor(bounds, z_index)!;
+
+	Id texture_id = ctx.font.id;  // or ctx.font.atlas.id
+	Rect text_bounds = {bounds.x, bounds.y, 0, 0};
+
+	TextInfo ti;
+	ti.init(&ctx.font, (String)text, bounds);
+
+	while (ti.place_glyph(reflow)!) {
+		if (!cull_rect(ti.glyph_bounds, bounds)) {
+			ctx.push_sprite(ti.glyph_bounds, ti.glyph_uv, texture_id, z_index, hue)!;
+		}
+	}
+	
+	ctx.push_scissor({}, z_index)!;
+
+	return ti;
+}
+
+fn void? Ctx.push_update_atlas(&ctx, Atlas* atlas)
+{
+	Cmd up = {
+		.type = CMD_UPDATE_ATLAS,
+		.update_atlas = {
+			.id = atlas.id,
+			.raw_buffer = atlas.buffer,
+			.width = atlas.width,
+			.height = atlas.height,
+			.bpp = (ushort)atlas.type.bpp(),
+			},
+		};
+	// update the atlases before everything else
+	ctx.push_cmd(&up, -1)!;
+}
+

lib/ugui.c3l/src/ugui_core.c3

@@ -0,0 +1,333 @@
+module ugui;
+
+import vtree;
+import cache;
+import fifo;
+
+import std::io;
+import std::core::string;
+import std::core::mem::allocator;
+
+
+// element ids are just long ints
+alias Id = uint;
+
+enum ElemType {
+	ETYPE_NONE,
+	ETYPE_DIV,
+	ETYPE_BUTTON,
+	ETYPE_SLIDER,
+	ETYPE_TEXT,
+	ETYPE_SPRITE,
+}
+
+bitstruct ElemFlags : uint {
+	bool updated : 0;
+	bool is_new : 1;
+}
+
+bitstruct ElemEvents : uint {
+	bool key_press     : 0;
+	bool key_release   : 1;
+	bool key_hold      : 2;
+	bool mouse_hover   : 3;
+	bool mouse_press   : 4;
+	bool mouse_release : 5;
+	bool mouse_hold    : 6;
+	bool update        : 7;
+	bool text_input    : 8;
+}
+
+// element structure
+struct Elem {
+	Id id;
+	isz tree_idx;
+	ElemFlags flags;
+	ElemEvents events;
+	Rect bounds;
+	ElemType type;
+	union {
+		ElemDiv div;
+		ElemButton button;
+		ElemSlider slider;
+		ElemText text;
+		ElemSprite sprite;
+	}
+}
+
+
+// relationships between elements are stored in a tree, it stores just the ids
+alias IdTree = vtree::VTree{Id};
+
+// elements themselves are kept in a cache
+const uint MAX_ELEMENTS = 256;
+alias ElemCache = cache::Cache{Id, Elem, MAX_ELEMENTS};
+
+alias CmdQueue = fifo::Fifo{Cmd};
+
+faultdef INVALID_SIZE, EVENT_UNSUPPORTED, WRONG_ELEMENT_TYPE, WRONG_ID;
+
+const Rect DIV_FILL = { .x = 0, .y = 0, .w = 0, .h = 0 };
+
+const uint STACK_STEP = 10;
+const uint MAX_ELEMS  = 128;
+const uint MAX_CMDS   = 2048;
+const uint ROOT_ID    = 1;
+const uint TEXT_MAX   = 64;
+
+struct Ctx {
+	IdTree tree;
+	ElemCache cache;
+	CmdQueue cmd_queue;
+	StyleMap styles;
+	// total size in pixels of the context
+	ushort width, height;
+	Font font;
+	SpriteAtlas sprite_atlas;
+
+	bool has_focus;
+	struct input {
+		InputEvents events;
+		struct mouse {
+			Point pos, delta;
+			// mouse_down:      bitmap of mouse buttons that are held
+			// mouse_updated:   bitmap of mouse buttons that have been updated
+			// mouse_released = mouse_updated & ~mouse_down
+			// mouse_pressed  = mouse_updated & mouse_down
+			MouseButtons down;
+			MouseButtons updated;
+			// scroll wheel
+			Point scroll;
+		}
+		struct keyboard {
+			char[TEXT_MAX] text;
+			usz text_len;
+			ModKeys modkeys;
+		}
+	}
+
+	Id hover_id;
+	Id focus_id;
+
+	Rect div_scissor; // the current div bounds used for scissor test
+	isz active_div; // tree node indicating the current active div
+}
+
+// return a pointer to the parent of the current active div
+fn Elem*? Ctx.get_parent(&ctx)
+{
+	Id parent_id = ctx.tree.get(ctx.active_div)!;
+	Elem*? parent = ctx.cache.search(parent_id);
+	if (catch parent) return parent;
+	if (parent.type != ETYPE_DIV) return WRONG_ELEMENT_TYPE?;
+	return parent; 
+}
+
+macro @bits(#a) => $typeof(#a).sizeof*8;
+macro Id.rotate_left(id, uint $n) => (id << $n) | (id >> (@bits(id) - $n));
+const uint GOLDEN_RATIO = 0x9E3779B9;
+
+// generate an id combining the hashes of the parent id and the label
+// with the Cantor pairing function
+fn Id? Ctx.gen_id(&ctx, Id id2)
+{
+	Id id1 = ctx.tree.get(ctx.active_div)!;
+	// Mix the two IDs non-linearly
+	Id mixed = id1 ^ id2.rotate_left(13);
+	mixed ^= id1.rotate_left(7);
+	mixed += GOLDEN_RATIO;
+	return mixed;
+}
+
+// compute the id from arguments and the line of the call
+macro Id @compute_id(...)
+{
+	Id id = (Id)$$LINE.hash() ^ (Id)@str_hash($$FILE);
+	$for var $i = 0; $i < $vacount; $i++:
+		id ^= (Id)$vaconst[$i].hash();
+	$endfor
+	return id;
+}
+
+// get or push an element from the cache, return a pointer to it
+// resets all flags except is_new which is set accordingly
+fn Elem*? Ctx.get_elem(&ctx, Id id, ElemType type)
+{
+	Elem empty_elem;
+	bool is_new;
+	Elem* elem;
+	elem = ctx.cache.get_or_insert(&empty_elem, id, &is_new)!;
+	elem.flags = (ElemFlags)0;
+	elem.flags.is_new = is_new;
+	elem.id = id;
+	if (is_new == false && elem.type != type) {
+		return WRONG_ELEMENT_TYPE?;
+	} else {
+		elem.type = type;
+	}
+	elem.tree_idx = ctx.tree.add(id, ctx.active_div)!;
+	return elem;
+}
+
+// find an element, does not allocate a new one in cache
+// THIS HAS TO BE A MACRO SINCE IT RETURNS A POINTER TO A TEMPORARY VALUE
+macro Elem* Ctx.find_elem(&ctx, Id id)
+{
+	Elem*? elem;
+	elem = ctx.cache.search(id);
+	if (catch elem) {
+		return &&(Elem){};
+	}
+	return elem;
+}
+
+fn Elem*? Ctx.get_active_div(&ctx)
+{
+	Id id = ctx.tree.get(ctx.active_div)!;
+	return ctx.cache.search(id);
+}
+
+fn void? Ctx.init(&ctx)
+{
+	ctx.tree.init(MAX_ELEMENTS)!;
+	defer catch { (void)ctx.tree.free(); }
+
+	ctx.cache.init()!;
+	defer catch { (void)ctx.cache.free(); }
+
+	ctx.cmd_queue.init(MAX_CMDS)!;
+	defer catch { (void)ctx.cmd_queue.free(); }
+
+	ctx.styles.init(allocator::heap());
+	ctx.styles.register_style(&DEFAULT_STYLE, @str_hash("default"));
+	defer catch { ctx.styles.free(); }
+
+	ctx.active_div = 0;
+}
+
+fn void Ctx.free(&ctx)
+{
+	(void)ctx.tree.free();
+	(void)ctx.cache.free();
+	(void)ctx.cmd_queue.free();
+	(void)ctx.font.free();
+	(void)ctx.sprite_atlas.free();
+	(void)ctx.styles.free();
+}
+
+fn void? Ctx.frame_begin(&ctx)
+{
+	// 1. Reset the active div
+	// 2. Get the root element from the cache and update it
+	ctx.active_div = 0;
+	Elem* elem = ctx.get_elem(ROOT_ID, ETYPE_DIV)!;
+	ctx.active_div = elem.tree_idx;
+	// The root should have the updated flag only if the size of the window
+	// was changed between frasmes, this propagates an element size recalculation
+	// down the element tree
+	elem.flags.updated = ctx.input.events.resize;
+	// if the window has focus then the root element also has focus, no other
+	// computation needed, child elements need to check the mouse positon and
+	// other stuff
+	//elem.flags.has_focus = ctx.has_focus;
+
+	elem.bounds = {0, 0, ctx.width, ctx.height};
+	elem.div.layout = LAYOUT_ROW;
+	elem.div.z_index = 0;
+	elem.div.children_bounds = elem.bounds;
+	elem.div.scroll_x.enabled = false;
+	elem.div.scroll_y.enabled = false;
+	elem.div.pcb = {};
+	elem.div.origin_c = {};
+	elem.div.origin_r = {};
+
+	ctx.div_scissor = {0, 0, ctx.width, ctx.height};
+
+	// The root element does not push anything to the stack
+	// TODO: add a background color taken from a theme or config
+}
+
+const int DEBUG = 1;
+
+fn void? Ctx.frame_end(&ctx)
+{
+	// FIXME: this is not guaranteed to be root. the user might forget to close a div or some other element
+	Elem* root = ctx.get_active_div()!;
+	if (root.id != ROOT_ID) return WRONG_ID?;
+
+	// 1. clear the tree
+	ctx.tree.nuke();
+
+	// 2. clear input fields
+	ctx.input.events = (InputEvents)0;
+	ctx.input.keyboard.text_len = 0;
+
+	// send atlas updates
+	if (ctx.font.should_update) {
+		ctx.push_update_atlas(&ctx.font.atlas)!;
+		ctx.font.should_update = false;
+	}
+	if (ctx.sprite_atlas.should_update) {
+		ctx.push_update_atlas(&ctx.sprite_atlas.atlas)!;
+		ctx.sprite_atlas.should_update = false;
+	}
+
+// debug
+$if DEBUG == 1:
+	// draw mouse position
+	Cmd cmd = {
+		.type = CMD_RECT,
+		.z_index = int.max-1, // hopefully over everything else
+		.rect.rect = {
+			.x = ctx.input.mouse.pos.x - 2,
+			.y = ctx.input.mouse.pos.y - 2,
+			.w = 4,
+			.h = 4,
+		},
+		.rect.color = 0xff00ffffu.to_rgba()
+	};
+	ctx.cmd_queue.enqueue(&cmd)!;
+$endif
+
+	// sort the command buffer by the z-index
+	ctx.cmd_queue.sort()!;
+}
+
+<*
+ * @ensure elem != null
+*>
+macro bool Ctx.is_hovered(&ctx, Elem *elem)
+{
+	return ctx.input.mouse.pos.in_rect(elem.bounds);
+}
+
+macro bool Ctx.elem_focus(&ctx, Elem *elem)
+{
+	return ctx.focus_id == elem.id;
+}
+
+// TODO: add other events
+// FIXME: this does not work with touch
+// FIXME: hacked together, please do better
+fn ElemEvents Ctx.get_elem_events(&ctx, Elem *elem)
+{
+	bool hover = ctx.is_hovered(elem);
+	bool focus = ctx.focus_id == elem.id || (hover && ctx.is_mouse_pressed(BTN_LEFT));
+
+	if (ctx.is_mouse_pressed(BTN_ANY) && !hover){
+		focus = false;
+		if (ctx.focus_id == elem.id) ctx.focus_id = 0;
+	}
+
+	if (hover) { ctx.hover_id = elem.id; }
+	if (focus) { ctx.focus_id = elem.id; }
+
+	ElemEvents ev = {
+		.mouse_hover = hover,
+		.mouse_press = hover && focus && ctx.is_mouse_pressed(BTN_ANY),
+		.mouse_release = hover && focus && ctx.is_mouse_released(BTN_ANY),
+		.mouse_hold = hover && focus && ctx.is_mouse_down(BTN_ANY),
+		.text_input = focus && (ctx.input.keyboard.text_len || ctx.input.keyboard.modkeys & KMOD_TXT),
+	};
+	return ev;
+}

lib/ugui.c3l/src/ugui_div.c3

@@ -0,0 +1,155 @@
+module ugui;
+
+import std::io;
+import std::math;
+
+// div element
+struct ElemDiv {
+	Layout layout;
+	struct scroll_x {
+		bool enabled;
+		bool on;
+		float value;
+	}
+	struct scroll_y {
+		bool enabled;
+		bool on;
+		float value;
+	}
+	ushort scroll_size;
+	int z_index;
+	Rect children_bounds; // current frame children bounds
+	Rect pcb; // previous frame children bounds
+	Point origin_r, origin_c;
+}
+
+// begin a widget container, or div, the size determines the offset (x,y) width and height.
+// if the width or height are zero the width or height are set to the maximum available.
+// if the width or height are negative the width or height will be calculated based on the children size
+// sort similar to a flexbox, and the minimum size is set by the negative of the width or height
+// FIXME: there is a bug if the size.w or size.h == -0
+macro Ctx.div_begin(&ctx, Rect size, bool scroll_x = false, bool scroll_y = false, ...)
+	=> ctx.div_begin_id(@compute_id($vasplat), size, scroll_x, scroll_y);
+fn void? Ctx.div_begin_id(&ctx, Id id, Rect size, bool scroll_x, bool scroll_y)
+{
+	id = ctx.gen_id(id)!;
+
+	Elem* elem = ctx.get_elem(id, ETYPE_DIV)!;
+	Elem* parent = ctx.get_parent()!;
+	ctx.active_div = elem.tree_idx;
+
+	Style* style = ctx.styles.get_style(@str_hash("default"));
+	Style* slider_style = ctx.styles.get_style(@str_hash("slider"));
+
+	elem.div.scroll_x.enabled = scroll_x;
+	elem.div.scroll_y.enabled = scroll_y;
+	elem.div.scroll_size = slider_style.size ? slider_style.size : (style.size ? style.size : DEFAULT_STYLE.size);
+	elem.div.z_index = parent.div.z_index + 1;
+
+	// 2. layout the element
+	Rect wanted_size = {
+		.x = size.x,
+		.y = size.y,
+		.w = size.w < 0 ? max(elem.div.pcb.w, (short)-size.w) : size.w,
+		.h = size.h < 0 ? max(elem.div.pcb.h, (short)-size.h) : size.h,
+	};
+	elem.bounds = ctx.layout_element(parent, wanted_size, style);
+	elem.div.children_bounds = {};
+
+	// update the ctx scissor
+	ctx.div_scissor = elem.bounds;
+	ctx.push_scissor(elem.bounds, elem.div.z_index)!;
+
+	// 4. Fill the div fields
+	elem.div.origin_c = {
+		.x = elem.bounds.x,
+		.y = elem.bounds.y
+	};
+	elem.div.origin_r = elem.div.origin_c;
+	elem.div.layout   = parent.div.layout;
+
+	// Add the background to the draw stack
+	bool do_border = parent.div.layout == LAYOUT_FLOATING;
+	ctx.push_rect(elem.bounds, elem.div.z_index, style)!;
+
+	elem.events = ctx.get_elem_events(elem);
+
+	// TODO: check active
+	// TODO: check resizeable
+}
+
+fn void? Ctx.div_end(&ctx)
+{
+	// swap the children bounds
+	Elem* elem = ctx.get_active_div()!;
+	elem.div.pcb = elem.div.children_bounds;
+
+	// FIXME: this causes all elements inside the div to loose focus since the mouse press happens
+	//        both inside the element and inside the div bounds
+	//elem.events = ctx.get_elem_events(elem);
+
+	Rect cb = elem.div.pcb;
+	// children bounds bottom-right corner
+	Point cbc = {
+		.x = cb.x + cb.w,
+		.y = cb.y + cb.h,
+	};
+	// div bounds bottom-right corner
+	Point bc = {
+		.x = elem.bounds.x + elem.bounds.w,
+		.y = elem.bounds.y + elem.bounds.h,
+	};
+
+	// set the scrollbar flag, is used in layout
+	// horizontal overflow
+	elem.div.scroll_x.on = cbc.x > bc.x && elem.div.scroll_x.enabled;
+	// vertical overflow
+	elem.div.scroll_y.on = cbc.y > bc.y && elem.div.scroll_y.enabled;
+
+	Id hsid_raw = @str_hash("div_scrollbar_horizontal");
+	Id vsid_raw = @str_hash("div_scrollbar_vertical");
+	Id hsid_real = ctx.gen_id(@str_hash("div_scrollbar_horizontal"))!;
+	Id vsid_real = ctx.gen_id(@str_hash("div_scrollbar_vertical"))!;
+	short wdim = elem.div.scroll_y.on ? (ctx.focus_id == vsid_real || ctx.is_hovered(ctx.find_elem(vsid_real)) ? elem.div.scroll_size*2 : elem.div.scroll_size) : 0;
+	short hdim = elem.div.scroll_x.on ? (ctx.focus_id == hsid_real || ctx.is_hovered(ctx.find_elem(hsid_real)) ? elem.div.scroll_size*2 : elem.div.scroll_size) : 0;
+
+	if (elem.div.scroll_y.on) {
+		if (ctx.input.events.mouse_scroll && ctx.hover_id == elem.id) {
+			elem.div.scroll_y.value += ctx.input.mouse.scroll.y * 0.07f;
+			elem.div.scroll_y.value = math::clamp(elem.div.scroll_y.value, 0.0f, 1.0f);
+		}
+		Rect vslider = {
+			.x = elem.bounds.x + elem.bounds.w - wdim,
+			.y = elem.bounds.y,
+			.w = wdim,
+			.h = elem.bounds.h - hdim,
+		};
+		Layout prev_l = elem.div.layout;
+		elem.div.layout = LAYOUT_ABSOLUTE;
+		ctx.slider_ver_id(vsid_raw, vslider, &elem.div.scroll_y.value, max((float)bc.y / cbc.y, (float)0.15))!;
+		elem.div.layout = prev_l;
+	}
+
+	if (elem.div.scroll_x.on) {
+		if (ctx.input.events.mouse_scroll && ctx.hover_id == elem.id) {
+			elem.div.scroll_x.value += ctx.input.mouse.scroll.x * 0.07f;
+			elem.div.scroll_x.value = math::clamp(elem.div.scroll_x.value, 0.0f, 1.0f);
+		}
+		Rect hslider = {
+			.x = elem.bounds.x,
+			.y = elem.bounds.y + elem.bounds.h - hdim,
+			.w = elem.bounds.w - wdim,
+			.h = hdim,
+		};
+		Layout prev_l = elem.div.layout;
+		elem.div.layout = LAYOUT_ABSOLUTE;
+		ctx.slider_hor_id(hsid_raw, hslider, &elem.div.scroll_x.value, max((float)bc.x / cbc.x, (float)0.15))!;
+		elem.div.layout = prev_l;
+	}
+
+	// the active_div returns to the parent of the current one
+	ctx.active_div = ctx.tree.parentof(ctx.active_div)!;
+	Elem* parent = ctx.get_parent()!;
+	// TODO: reset the scissor back to the parent div
+	ctx.div_scissor = parent.bounds;
+}

lib/ugui.c3l/src/ugui_font.c3

@@ -0,0 +1,314 @@
+module ugui;
+
+import schrift;
+import grapheme;
+import std::collections::map;
+import std::core::mem;
+import std::core::mem::allocator;
+import std::io;
+import std::ascii;
+
+
+// unicode code point, different type for a different hash
+alias Codepoint = uint;
+
+//macro uint Codepoint.hash(self) => ((uint)self).hash();
+
+/* width and height of a glyph contain the kering advance
+ * (u,v)
+ *   +-------------*---+ -
+ *   |       ^     |   | ^
+ *   |       |oy   |   | |
+ *   |       v     |   | |
+ *   |      .ii.   |   | |
+ *   |     @@@@@@. |   | |
+ *   |    V@Mio@@o |   | |
+ *   |    :i.  V@V |   | h
+ *   |      :oM@@M |   | |
+ *   |    :@@@MM@M |   | |
+ *   |    @@o  o@M |   | |
+ *   |<->:@@.  M@M |   | |
+ *   |ox  @@@o@@@@ |   | |
+ *   |    :M@@V:@@.|   | v
+ *   +-------------*---+ -
+ *   |<---- w ---->|
+ *   |<------ adv ---->|
+ */
+struct Glyph {
+	Codepoint code;
+	ushort u, v;
+	ushort w, h;
+	short adv, ox, oy;
+}
+
+const uint FONT_CACHED = 255;
+alias GlyphTable = map::HashMap{Codepoint, Glyph};
+
+faultdef TTF_LOAD_FAILED, MISSING_GLYPH, BAD_GLYPH_METRICS, RENDER_ERROR;
+
+struct Font {
+	schrift::Sft sft;
+	String path;
+	Id id; // font id, same as atlas id
+	GlyphTable table;
+
+	float size;
+	float ascender, descender, linegap; // Line Metrics
+	Atlas atlas;
+	bool should_update; // should send update_atlas command, resets at frame_end()
+}
+
+fn void? Font.load(&font, String name, ZString path, uint height, float scale)
+{
+	font.table.init(allocator::heap(), capacity: FONT_CACHED);
+	font.id = name.hash();
+
+	font.size = height*scale;
+
+	font.sft = {
+		.xScale = (double)font.size,
+		.yScale = (double)font.size,
+		.flags = schrift::SFT_DOWNWARD_Y,
+	};
+
+	font.sft.font = schrift::loadfile(path);
+	if (font.sft.font == null) {
+		font.table.free();
+		return TTF_LOAD_FAILED?;
+	}
+
+	schrift::SftLMetrics lmetrics;
+	schrift::lmetrics(&font.sft, &lmetrics);
+	font.ascender  = (float)lmetrics.ascender;
+	font.descender = (float)lmetrics.descender;
+	font.linegap   = (float)lmetrics.lineGap;
+	//io::printfn("ascender:%d, descender:%d, linegap:%d", font.ascender, font.descender, font.linegap);
+
+	// TODO: allocate buffer based on FONT_CACHED and the size of a sample letter
+	//       like the letter 'A'
+	ushort size = (ushort)font.size*(ushort)($$sqrt((float)FONT_CACHED));
+	font.atlas.new(font.id, ATLAS_GRAYSCALE, size, size)!;
+
+	// preallocate the ASCII range
+	for (char c = ' '; c < '~'; c++) {
+		font.get_glyph((Codepoint)c)!;
+	}
+}
+
+fn Glyph*? Font.get_glyph(&font, Codepoint code)
+{
+	Glyph*? gp;
+	gp = font.table.get_ref(code);
+
+	if (catch excuse = gp) {
+		if (excuse != NOT_FOUND) {
+			return excuse?;
+		}
+	} else {
+		return gp;
+	}
+
+	// missing glyph, render and place into an atlas
+	Glyph glyph;
+
+	schrift::SftGlyph gid;
+	schrift::SftGMetrics gmtx;
+
+	if (schrift::lookup(&font.sft, (SftUChar)code, &gid) < 0) {
+		return MISSING_GLYPH?;
+	}
+
+	if (schrift::gmetrics(&font.sft, gid, &gmtx) < 0) {
+		return BAD_GLYPH_METRICS?;
+	}
+
+	schrift::SftImage img = {
+		.width = gmtx.minWidth,
+		.height = gmtx.minHeight,
+	};
+	char[] pixels = mem::new_array(char, (usz)img.width * img.height);
+	img.pixels = pixels;
+	if (schrift::render(&font.sft, gid, img) < 0) {
+		return RENDER_ERROR?;
+	}
+
+	glyph.code = code;
+	glyph.w = (ushort)img.width;
+	glyph.h = (ushort)img.height;
+	glyph.ox = (short)gmtx.leftSideBearing;
+	glyph.oy = (short)gmtx.yOffset;
+	glyph.adv = (short)gmtx.advanceWidth;
+	//io::printfn("code=%c, w=%d, h=%d, ox=%d, oy=%d, adv=%d",
+	//    glyph.code, glyph.w, glyph.h, glyph.ox, glyph.oy, glyph.adv);
+
+	Point uv = font.atlas.place(pixels, glyph.w, glyph.h, (ushort)img.width)!;
+	glyph.u = uv.x;
+	glyph.v = uv.y;
+
+	mem::free(pixels);
+
+	font.table.set(code, glyph);
+
+	font.should_update = true;
+	return font.table.get_ref(code);
+}
+
+fn void Font.free(&font)
+{
+	font.atlas.free();
+	font.table.free();
+	schrift::freefont(font.sft.font);
+}
+
+fn void? Ctx.load_font(&ctx, String name, ZString path, uint height, float scale = 1.0)
+{
+	return ctx.font.load(name, path, height, scale);
+}
+
+<*
+@require off != null
+@require str.ptr != null
+*>
+fn Codepoint str_to_codepoint(char[] str, usz* off)
+{
+	Codepoint cp;
+	isz b = grapheme::decode_utf8(str, str.len, (uint*)&cp);
+	if (b == 0 || b > str.len) {
+		return 0;
+	}
+	*off = b;
+	return cp;
+}
+
+const uint TAB_SIZE = 4;
+
+// TODO: change the name
+// TODO: reorder to make smaller
+struct TextInfo {
+	Font* font;
+	Rect bounds;
+	String text;
+	usz off;
+	
+	// current glyph info
+	Point origin;
+	Rect glyph_bounds;
+	Rect glyph_uv;
+	
+	// cursor info
+	usz cursor_idx;
+	Point cursor_pos;
+	
+	// current text bounds
+	Rect text_bounds;
+}
+
+<*
+@require f != null
+*>
+fn void TextInfo.init(&self, Font* f, String s, Rect bounds = RECT_MAX)
+{
+	*self = {};
+	self.font = f;
+	self.text = s;
+	self.bounds = bounds;
+	self.origin = bounds.position();
+	self.text_bounds = { .x = bounds.x, .y = bounds.y };
+}
+
+fn void TextInfo.reset(&self)
+{
+	TextInfo old = *self;
+	self.init(old.font, old.text, old.bounds);
+}
+
+fn bool? TextInfo.place_glyph(&self, bool reflow)
+{
+	if (self.off >= self.text.len) {
+		return false;
+	}
+	if (!self.origin.in_rect(self.bounds)) {
+		return false;
+	}
+
+	short baseline = (short)self.font.ascender;
+	short line_height = (short)self.font.ascender - (short)self.font.descender;
+	short line_gap = (short)self.font.linegap;
+
+	Codepoint cp;
+	Glyph* gp;
+	usz x;
+	
+	cp = str_to_codepoint(self.text[self.off..], &x);
+	if (cp == 0) return false;
+	self.off += x;
+
+	if (ascii::is_cntrl((char)cp) == false) {
+		gp = self.font.get_glyph(cp)!;
+		self.glyph_uv = {
+			.x = gp.u,
+			.y = gp.v,
+			.w = gp.w,
+			.h = gp.h,
+		};
+		self.glyph_bounds = {
+			.x = self.origin.x + gp.ox,
+			.y = self.origin.y + gp.oy + baseline,
+			.w = gp.w,
+			.h = gp.h,
+		};
+		// try to wrap the text if the charcater goes outside of the bounds
+		if (reflow && !self.bounds.contains(self.glyph_bounds)) {
+			self.origin.y += line_height + line_gap;
+			self.glyph_bounds.y += line_height + line_gap;
+
+			self.origin.x = self.bounds.x;
+			self.glyph_bounds.x = self.bounds.x;
+		}
+
+		// handle tab
+		if (cp == '\t') {
+			self.origin.x += gp.adv*TAB_SIZE;
+		} else {
+			self.origin.x += gp.adv;
+		}
+
+	} else if (cp == '\n'){
+		self.origin.y += line_height + line_gap;
+		self.origin.x = self.bounds.x;
+	}
+
+	self.text_bounds = containing_rect(self.text_bounds, self.glyph_bounds);
+
+	if (self.off == self.cursor_idx) {
+		self.cursor_pos = self.origin;
+	}
+
+	return true;
+}
+
+fn Rect? Ctx.get_text_bounds(&ctx, String text)
+{
+	TextInfo ti;
+	ti.init(&ctx.font, text);
+	while (ti.place_glyph(false)!);
+	return ti.text_bounds;
+}
+
+// TODO: check if the font is present in the context
+fn Id Ctx.get_font_id(&ctx, String label)
+{
+	return (Id)label.hash();
+}
+
+fn Atlas*? Ctx.get_font_atlas(&ctx, String name)
+{
+	// TODO: use the font name, for now there is only one font
+	if (name.hash() != ctx.font.id) {
+		return WRONG_ID?;
+	}
+
+	return &ctx.font.atlas;
+}
+
+fn int Font.line_height(&font) => (int)(font.ascender - font.descender + (float)0.5);

lib/ugui.c3l/src/ugui_input.c3

@@ -0,0 +1,204 @@
+module ugui;
+
+import grapheme;
+import std::io;
+import std::math;
+import std::core::string;
+
+bitstruct InputEvents : uint {
+	bool resize       : 0; // window size was changed
+	bool change_focus : 1; // window focus changed
+	bool mouse_move   : 2; // mouse was moved
+	bool mouse_btn    : 3; // mouse button pressed or released
+	bool mouse_scroll : 4; // mouse scroll wheel. x or y
+	bool text_input   : 5;
+	bool mod_key      : 6;
+}
+
+bitstruct MouseButtons : uint {
+	bool btn_left   : 0;
+	bool btn_middle : 1;
+	bool btn_right  : 2;
+	bool btn_4      : 3;
+	bool btn_5      : 4;
+}
+
+// FIXME: all of these names were prefixed with key_ idk if this is better,
+//        if it is remove the prefix on MouseButtons as well
+// Modifier Keys, intended as any key that is not text
+bitstruct ModKeys : uint {
+	bool lshift :  0;
+	bool rshift :  1;
+	bool lctrl  :  2;
+	bool rctrl  :  3;
+	bool lalt   :  4;
+	bool ralt   :  5;
+	bool lgui   :  6;
+	bool rgui   :  7;
+	bool num    :  8;
+	bool caps   :  9;
+	bool mode   : 10;
+	bool scroll : 11;
+	bool bkspc  : 12;
+	bool del    : 13;
+	// arrow keys
+	bool up     : 14;
+	bool down   : 15;
+	bool left   : 16;
+	bool right  : 17;
+}
+
+const ModKeys KMOD_CTRL  = {.lctrl  = true, .rctrl  = true};
+const ModKeys KMOD_SHIFT = {.lshift = true, .rshift = true};
+const ModKeys KMOD_ALT   = {.lalt   = true, .ralt   = true};
+const ModKeys KMOD_GUI   = {.lgui   = true, .rgui   = true};
+const ModKeys KMOD_TXT   = {.bkspc  = true, .del    = true}; // modkeys that act like text input
+const ModKeys KMOD_NONE  = {};
+const ModKeys KMOD_ANY   = (ModKeys)(ModKeys.inner.max);
+
+const MouseButtons BTN_NONE   = {};
+const MouseButtons BTN_ANY    = (MouseButtons)(MouseButtons.inner.max);
+const MouseButtons BTN_LEFT   = {.btn_left   = true};
+const MouseButtons BTN_MIDDLE = {.btn_middle = true};
+const MouseButtons BTN_RIGHT  = {.btn_right  = true};
+const MouseButtons BTN_4      = {.btn_4      = true};
+const MouseButtons BTN_5      = {.btn_5      = true};
+
+const ModKeys KEY_ANY = (ModKeys)(ModKeys.inner.max);
+
+fn bool Ctx.check_key_combo(&ctx, ModKeys mod, String keys)
+{
+	bool is_mod = (bool)(ctx.input.keyboard.modkeys & mod);
+	bool is_keys = true;
+	String haystack = (String)ctx.input.keyboard.text[0..ctx.input.keyboard.text_len];
+	char[2] needle;
+	foreach (c: keys) {
+		needle[0] = c;
+		is_keys = is_keys && haystack.contains((String)needle[..]);
+	}
+	return is_mod && is_keys;
+}
+
+// Window size was changed
+fn void? Ctx.input_window_size(&ctx, short width, short height)
+{
+	if (width <= 0 || height <= 0) {
+		return INVALID_SIZE?;
+	}
+	ctx.input.events.resize = ctx.width != width || ctx.height != height;
+	ctx.width = width;
+	ctx.height = height;
+}
+
+// Window gained/lost focus
+fn void Ctx.input_changefocus(&ctx, bool has_focus)
+{
+	// FIXME: raylib only has an API to query the focus status so we have to
+	//        update the input flag only if the focus changed
+	ctx.input.events.change_focus = ctx.has_focus != has_focus;
+	ctx.has_focus = has_focus;
+}
+
+macro Ctx.mouse_pressed(&ctx) => ctx.input.mouse.updated & ctx.input.mouse.down;
+macro Ctx.mouse_released(&ctx) => ctx.input.mouse.updated & ~ctx.input.mouse.down;
+macro Ctx.mouse_down(&ctx) => ctx.input.mouse.down;
+
+// FIXME: hthis compairson could be done with a cast using MouseButtons.inner
+// property but I could not figure out how
+macro Ctx.is_mouse_pressed(&ctx, MouseButtons btn) => (ctx.mouse_pressed() & btn) != BTN_NONE;
+macro Ctx.is_mouse_released(&ctx, MouseButtons btn) => (ctx.mouse_released() & btn) != BTN_NONE;
+macro Ctx.is_mouse_down(&ctx, MouseButtons btn) => (ctx.mouse_down() & btn) != BTN_NONE;
+
+// Mouse Buttons down
+fn void Ctx.input_mouse_button(&ctx, MouseButtons buttons)
+{
+	ctx.input.mouse.updated = ctx.input.mouse.down ^ buttons;
+	ctx.input.mouse.down = buttons;
+	ctx.input.events.mouse_btn = (uint)ctx.input.mouse.down != 0 || (uint)ctx.input.mouse.updated != 0;
+}
+
+// Mouse was moved, report absolute position
+fn void Ctx.input_mouse_abs(&ctx, short x, short y)
+{
+	ctx.input.mouse.pos.x = math::clamp(x, (short)0, ctx.width);
+	ctx.input.mouse.pos.y = math::clamp(y, (short)0, ctx.height);
+
+	short dx, dy;
+	dx = x - ctx.input.mouse.pos.x;
+	dy = y - ctx.input.mouse.pos.y;
+
+	ctx.input.mouse.delta.x = dx;
+	ctx.input.mouse.delta.y = dy;
+
+	ctx.input.events.mouse_move = dx != 0 || dy != 0;
+}
+
+// Mouse was moved, report relative motion
+fn void Ctx.input_mouse_delta(&ctx, short dx, short dy)
+{
+	ctx.input.mouse.delta.x = dx;
+	ctx.input.mouse.delta.y = dy;
+
+	short mx, my;
+	mx = ctx.input.mouse.pos.x + dx;
+	my = ctx.input.mouse.pos.y + dy;
+
+	ctx.input.mouse.pos.x = math::clamp(mx, (short)0, ctx.width);
+	ctx.input.mouse.pos.y = math::clamp(my, (short)0, ctx.height);
+
+	ctx.input.events.mouse_move = dx != 0 || dy != 0;
+}
+
+fn void Ctx.input_mouse_wheel(&ctx, short x, short y, float scale = 1.0)
+{
+	ctx.input.mouse.scroll.x = (short)((float)-x*scale);
+	ctx.input.mouse.scroll.y = (short)((float)-y*scale);
+	ctx.input.events.mouse_scroll = x !=0 || y != 0;
+}
+
+// append utf-8 encoded text to the context text input
+fn void Ctx.input_text_utf8(&ctx, char[] text)
+{
+	if (text.len == 0) { return; }
+
+	usz remaining = ctx.input.keyboard.text.len - ctx.input.keyboard.text_len;
+	usz len = text.len > remaining ? remaining : text.len;
+	char[] s = ctx.input.keyboard.text[ctx.input.keyboard.text_len ..];
+	s[..len-1] = text[..len-1];
+	ctx.input.keyboard.text_len += len;
+	ctx.input.events.text_input = true;
+}
+
+fn void Ctx.input_text_unicode(&ctx, char[] text)
+{
+	if (text.ptr == null || text.len == 0) { return; }
+
+	char[32] tmp;
+	usz remaining = ctx.input.keyboard.text.len - ctx.input.keyboard.text_len;
+	char[] s = ctx.input.keyboard.text[ctx.input.keyboard.text_len ..];
+
+	usz off;
+	foreach (idx, cp: text) {
+		if (off >= remaining) { break; }
+		usz enc = grapheme::encode_utf8(cp, tmp[..], tmp.len);
+		s[off..off+enc] = tmp[..enc];
+		off += enc;
+	}
+	ctx.input.keyboard.text_len += off;
+
+	ctx.input.events.text_input = true;
+}
+
+fn void Ctx.input_char(&ctx, char c)
+{
+	char[1] b = {c};
+	ctx.input_text_utf8(b[..]);
+}
+
+// Modifier keys, like control or backspace
+// TODO: make this call repetible to input modkeys one by one
+fn void Ctx.input_mod_keys(&ctx, ModKeys modkeys)
+{
+	ctx.input.keyboard.modkeys = modkeys;
+	ctx.input.events.mod_key = (uint)ctx.input.keyboard.modkeys != 0;
+}

lib/ugui.c3l/src/ugui_layout.c3

@@ -0,0 +1,157 @@
+module ugui;
+
+enum Layout {
+	LAYOUT_ROW,
+	LAYOUT_COLUMN,
+	LAYOUT_FLOATING,
+	LAYOUT_ABSOLUTE,
+}
+
+fn void? Ctx.layout_set_row(&ctx)
+{
+	Elem *parent = ctx.get_parent()!;
+	parent.div.layout = LAYOUT_ROW;
+}
+
+fn void? Ctx.layout_set_column(&ctx)
+{
+	Elem *parent = ctx.get_parent()!;
+	parent.div.layout = LAYOUT_COLUMN;
+}
+
+fn void? Ctx.layout_set_floating(&ctx)
+{
+	Elem *parent = ctx.get_parent()!;
+	parent.div.layout = LAYOUT_FLOATING;
+}
+
+fn void? Ctx.layout_next_row(&ctx)
+{
+	Elem *parent = ctx.get_parent()!;
+
+	parent.div.origin_r = {
+		.x = parent.bounds.x,
+		.y = parent.div.children_bounds.bottom_right().y,
+	};
+	parent.div.origin_c = parent.div.origin_r;
+}
+
+fn void? Ctx.layout_next_column(&ctx)
+{
+	Elem *parent = ctx.get_parent()!;
+
+	parent.div.origin_c = {
+		.x = parent.div.children_bounds.bottom_right().x,
+		.y = parent.bounds.y,
+	};
+	parent.div.origin_r = parent.div.origin_c;
+}
+
+macro Rect Elem.content_bounds(&elem, style) => elem.bounds.pad(style.border).pad(style.padding);
+
+macro Rect Elem.get_view(&elem)
+{
+	Rect off;
+	if (elem.div.scroll_x.enabled && elem.div.scroll_x.on) {
+		off.x = (short)((float)(elem.div.pcb.w - elem.bounds.w) * elem.div.scroll_x.value);
+		off.w = -elem.div.scroll_size;
+	}
+	if (elem.div.scroll_y.enabled && elem.div.scroll_y.on) {
+		off.y = (short)((float)(elem.div.pcb.h - elem.bounds.h) * elem.div.scroll_y.value);
+		off.h = -elem.div.scroll_size;
+	}
+	return elem.bounds.add(off);
+}
+
+macro Point Elem.get_view_off(&elem)
+{
+	return elem.get_view().sub(elem.bounds).position();
+}
+
+// position the rectangle inside the parent according to the layout
+// parent: parent div
+// rect: the requested size
+// style: apply style
+<*
+@require ctx != null
+@require parent.type == ETYPE_DIV
+*>
+fn Rect Ctx.layout_element(&ctx, Elem *parent, Rect rect, Style* style)
+{
+	ElemDiv* div = &parent.div;
+
+	Rect parent_bounds, parent_view;
+	Rect child_placement, child_occupied;
+
+	// 1. Select the right origin
+	Point origin;
+	switch (div.layout) {
+	case LAYOUT_ROW:
+		origin = div.origin_r;
+	case LAYOUT_COLUMN:
+		origin = div.origin_c;
+	case LAYOUT_FLOATING: // none, relative to zero zero
+	case LAYOUT_ABSOLUTE: // absolute position, this is a no-op, return the rect
+		return rect;
+	default: // error
+		return {};
+	}
+
+	// 2. Compute the parent's view
+	parent_bounds = parent.bounds;
+	parent_view = parent.get_view();
+
+	// 3. Compute the placement and occupied area
+
+	// grow rect (wanted size) when widht or height are less than zero
+	bool adapt_x = rect.w <= 0;
+	bool adapt_y = rect.h <= 0;
+	if (adapt_x) rect.w = parent_bounds.w - parent_bounds.x - origin.x;
+	if (adapt_y) rect.h = parent_bounds.h - parent_bounds.y - origin.y;
+
+	// offset placement and area
+	child_placement = child_placement.off(origin.add(rect.position()));
+	child_occupied  = child_occupied.off(origin.add(rect.position()));
+
+	Rect margin  = style.margin;
+	Rect border  = style.border;
+	Rect padding = style.padding;
+
+	// padding, grows both the placement and occupied area
+	child_placement = child_placement.grow(padding.position().add(padding.size()));
+	child_occupied  = child_occupied.grow(padding.position().add(padding.size()));
+	// border, grows both the placement and occupied area
+	child_placement = child_placement.grow(border.position().add(border.size()));
+	child_occupied  = child_occupied.grow(border.position().add(border.size()));
+	// margin, offsets the placement and grows the occupied area
+	child_placement = child_placement.off(margin.position());
+	child_occupied  = child_occupied.grow(margin.position().add(margin.size()));
+
+	// oh yeah also adjust the rect if i was to grow
+	if (adapt_x) rect.w -= padding.x+padding.w + border.x+border.w + margin.x+margin.w;
+	if (adapt_y) rect.h -= padding.y+padding.h + border.y+border.h + margin.y+margin.h;
+
+	// set the size
+	child_placement = child_placement.grow(rect.size());
+	child_occupied  = child_occupied.grow(rect.size());
+
+	// 4. Update the parent's origin
+	div.origin_r = {
+		.x = child_occupied.bottom_right().x,
+		.y = origin.y,
+	};
+	div.origin_c = {
+		.x = origin.x,
+		.y = child_occupied.bottom_right().y,
+	};
+
+	// 5. Update the parent's children bounds
+	div.children_bounds = containing_rect(div.children_bounds, child_occupied);
+
+	// 99. return the placement
+	if (child_placement.collides(parent_view)) {
+		return child_placement.off(parent.get_view_off().neg());
+	} else {
+		return {};
+	}
+}

lib/ugui.c3l/src/ugui_shapes.c3

@@ -0,0 +1,259 @@
+module ugui;
+
+
+// ---------------------------------------------------------------------------------- //
+//                                  RECTANGLE                                         //
+// ---------------------------------------------------------------------------------- //
+
+// Rect and it's methods
+struct Rect {
+	short x, y, w, h;
+}
+
+// TODO: find another name
+const Rect RECT_MAX = {0, 0, short.max, short.max};
+
+// return true if rect a contains b
+macro bool Rect.contains(Rect a, Rect b)
+{
+	return (a.x <= b.x && a.y <= b.y && a.x+a.w >= b.x+b.w && a.y+a.h >= b.y+b.h);
+}
+
+// returns the intersection of a and b
+macro Rect Rect.intersection(Rect a, Rect b)
+{
+	return {
+		.x = (short)max(a.x, b.x),
+		.y = (short)max(a.y, b.y),
+		.w = (short)min(a.x+a.w, b.x+b.w) - (short)max(a.x, b.x),
+		.h = (short)min(a.y+a.h, b.y+b.h) - (short)max(a.y, b.y),
+	};
+}
+
+// returns true if the intersection not null
+macro bool Rect.collides(Rect a, Rect b)
+{
+	return !(a.x > b.x+b.w || a.x+a.w < b.x || a.y > b.y+b.h || a.y+a.h < b.y);
+}
+
+// return a rect that contains both rects, a bounding box of both
+macro Rect containing_rect(Rect a, Rect b)
+{
+	short min_x = (short)min(a.x, b.x);
+	short min_y = (short)min(a.y, b.y);
+	short max_x = (short)max(a.x + a.w, b.x + b.w);
+	short max_y = (short)max(a.y + a.h, b.y + b.h);
+	return {
+		.x = min_x,
+		.y = min_y,
+		.w = (short)(max_x - min_x),
+		.h = (short)(max_y - min_y)
+	};
+}
+
+// check for empty rect
+macro bool Rect.is_null(Rect r) => r.x == 0 && r.y == 0 && r.x == 0 && r.w == 0;
+
+// returns the element-wise addition of r1 and r2
+macro Rect Rect.add(Rect r1, Rect r2)
+{
+	return {
+		.x = r1.x + r2.x,
+		.y = r1.y + r2.y,
+		.w = r1.w + r2.w,
+		.h = r1.h + r2.h,
+	};
+}
+
+// returns the element-wise subtraction of r1 and r2
+macro Rect Rect.sub(Rect r1, Rect r2)
+{
+	return {
+		.x = r1.x - r2.x,
+		.y = r1.y - r2.y,
+		.w = r1.w - r2.w,
+		.h = r1.h - r2.h,
+	};
+}
+
+// returns the element-wise multiplication of r1 and r2
+macro Rect Rect.mul(Rect r1, Rect r2)
+{
+	return {
+		.x = r1.x * r2.x,
+		.y = r1.y * r2.y,
+		.w = r1.w * r2.w,
+		.h = r1.h * r2.h,
+	};
+}
+
+macro Point Rect.position(Rect r)
+{
+	return {
+		.x = r.x,
+		.y = r.y,
+	};
+}
+
+macro Point Rect.size(Rect r)
+{
+	return {
+		.x = r.w,
+		.y = r.h,
+	};
+}
+
+macro Rect Rect.max(Rect a, Rect b)
+{
+	return {
+		.x = max(a.x, b.x),
+		.y = max(a.y, b.y),
+		.w = max(a.w, b.w),
+		.h = max(a.h, b.h),
+	};
+}
+
+macro Rect Rect.min(Rect a, Rect b)
+{
+	return {
+		.x = min(a.x, b.x),
+		.y = min(a.y, b.y),
+		.w = min(a.w, b.w),
+		.h = min(a.h, b.h),
+	};
+}
+
+// Offset a rect by a point
+macro Rect Rect.off(Rect r, Point p)
+{
+	return {
+		.x = r.x + p.x,
+		.y = r.y + p.y,
+		.w = r.w,
+		.h = r.h,
+	};
+}
+
+// Resize a rect width and height
+macro Rect Rect.grow(Rect r, Point p)
+{
+	return {
+		.x = r.x,
+		.y = r.y,
+		.w = r.w + p.x,
+		.h = r.h + p.y,
+	};
+}
+
+// Return the bottom-right corner of a rectangle
+macro Point Rect.bottom_right(Rect r)
+{
+	return {
+		.x = r.x + r.w,
+		.y = r.y + r.h,
+	};
+}
+
+macro Rect Rect.center_to(Rect a, Rect b)
+{
+	return {
+		.x = b.x + (b.w - a.w)/2,
+		.y = b.y + (b.h - a.h)/2,
+		.w = a.w,
+		.h = a.h,
+	};
+}
+
+macro Rect Rect.pad(Rect a, Rect b)
+{
+	return {
+		.x = a.x + b.x,
+		.y = a.y + b.y,
+		.w = a.w - b.x - b.w,
+		.h = a.h - b.y - b.h,
+	};
+}
+
+
+// ---------------------------------------------------------------------------------- //
+//                                    POINT                                           //
+// ---------------------------------------------------------------------------------- //
+
+struct Point {
+	short x, y;
+}
+
+// returns true if a point is inside the rectangle
+macro bool Point.in_rect(Point p, Rect r)
+{
+	return (p.x >= r.x && p.x <= r.x + r.w) && (p.y >= r.y && p.y <= r.y + r.h);
+}
+
+macro Point Point.add(Point a, Point b)
+{
+	return {
+		.x = a.x + b.x,
+		.y = a.y + b.y,
+	};
+}
+
+macro Point Point.sub(Point a, Point b)
+{
+	return {
+		.x = a.x - b.x,
+		.y = a.y - b.y,
+	};
+}
+
+macro Point Point.neg(Point p) => {-p.x, -p.y};
+
+macro Point Point.max(Point a, Point b)
+{
+	return {
+		.x = max(a.x, b.x),
+		.y = max(a.y, b.y),
+	};
+}
+
+macro Point Point.min(Point a, Point b)
+{
+	return {
+		.x = min(a.x, b.x),
+		.y = min(a.y, b.y),
+	};
+}
+
+// ---------------------------------------------------------------------------------- //
+//                                    COLOR                                           //
+// ---------------------------------------------------------------------------------- //
+
+struct Color{
+	char r, g, b, a;
+}
+
+macro Color uint.to_rgba(u)
+{
+	return {
+		.r = (char)((u >> 24) & 0xff),
+		.g = (char)((u >> 16) & 0xff),
+		.b = (char)((u >> 8) & 0xff),
+		.a = (char)((u >> 0) & 0xff)
+	};
+}
+
+
+macro Color uint.@to_rgba($u)
+{
+	return {
+		.r = (char)(($u >> 24) & 0xff),
+		.g = (char)(($u >> 16) & 0xff),
+		.b = (char)(($u >> 8) & 0xff),
+		.a = (char)(($u >> 0) & 0xff)
+	};
+}
+
+macro uint Color.to_uint(c)
+{
+	uint u = c.r | (c.g << 8) | (c.b << 16) | (c.a << 24);
+	return u;
+}

lib/ugui.c3l/src/ugui_slider.c3

@@ -0,0 +1,136 @@
+module ugui;
+
+import std::io;
+import std::math;
+
+// slider element
+struct ElemSlider {
+	Rect handle;
+}
+
+
+/*       handle
+ * +----+-----+---------------------+
+ * |    |#####|                     |
+ * +----+-----+---------------------+
+ */
+macro Ctx.slider_hor(&ctx, Rect size, float* value, float hpercent = 0.25, ...)
+	=> ctx.slider_hor_id(@compute_id($vasplat), size, value, hpercent);
+<*
+@require value != null
+*>
+fn ElemEvents? Ctx.slider_hor_id(&ctx, Id id, Rect size, float* value, float hpercent = 0.25)
+{
+	id = ctx.gen_id(id)!;
+
+	Elem* parent = ctx.get_parent()!;
+	Elem* elem = ctx.get_elem(id, ETYPE_SLIDER)!;
+	Style* style = ctx.styles.get_style(@str_hash("slider"));
+
+	// 2. Layout
+	elem.bounds = ctx.layout_element(parent, size, style);
+	if (elem.bounds.is_null()) return {};
+	Rect content_bounds = elem.content_bounds(style);
+
+	// handle width
+	short hw = (short)(content_bounds.w * hpercent);
+	Rect handle = {
+		.x = calc_slider(content_bounds.x, content_bounds.w-hw, *value),
+		.y = content_bounds.y,
+		.w = hw,
+		.h = content_bounds.h,
+	};
+	elem.slider.handle = handle;
+
+	Point m = ctx.input.mouse.pos;
+	elem.events = ctx.get_elem_events(elem);
+
+	if (ctx.elem_focus(elem) && ctx.is_mouse_down(BTN_LEFT)) {
+		*value = calc_value(content_bounds.x, m.x, content_bounds.w, hw);
+		elem.slider.handle.x = calc_slider(content_bounds.x, content_bounds.w-hw, *value);
+		elem.events.update = true;
+	}
+
+	// Draw the slider background and handle
+	Style s = *style;
+	Rect padding = s.padding;
+	s.padding = {};
+	ctx.push_rect(elem.bounds, parent.div.z_index, &s)!;
+	s.bg = s.primary;
+	s.padding = padding;
+	s.border = {};
+	ctx.push_rect(elem.slider.handle, parent.div.z_index, &s)!;
+
+	return elem.events;
+}
+
+
+/*
+ * +--+
+ * |  |
+ * |  |
+ * +--+
+ * |##| handle
+ * |##|
+ * +--+
+ * |  |
+ * |  |
+ * +--+
+ */
+macro Ctx.slider_ver(&ctx, Rect size, float* value, float hpercent = 0.25, ...)
+	=> ctx.slider_ver_id(@compute_id($vasplat), size, value, hpercent);
+fn ElemEvents? Ctx.slider_ver_id(&ctx, Id id, Rect size, float* value, float hpercent = 0.25)
+{
+	id = ctx.gen_id(id)!;
+
+	Elem *parent = ctx.get_parent()!;
+	Elem *elem = ctx.get_elem(id, ETYPE_SLIDER)!;
+	Style* style = ctx.styles.get_style(@str_hash("slider"));
+
+	// 1. Fill the element fields
+	if (elem.flags.is_new) {
+		elem.type = ETYPE_SLIDER;
+	} else if (elem.type != ETYPE_SLIDER) {
+		return WRONG_ELEMENT_TYPE?;
+	}
+
+	// 2. Layout
+	elem.bounds = ctx.layout_element(parent, size, style);
+	if (elem.bounds.is_null()) return {};
+	Rect content_bounds = elem.content_bounds(style);
+
+	// handle height
+	short hh = (short)(content_bounds.h * hpercent);
+	Rect handle = {
+		.x = content_bounds.x,
+		.y = calc_slider(content_bounds.y, content_bounds.h-hh, *value),
+		.w = content_bounds.w,
+		.h = hh,
+	};
+	elem.slider.handle = handle;
+
+	Point m = ctx.input.mouse.pos;
+	elem.events = ctx.get_elem_events(elem);
+
+	if (ctx.elem_focus(elem) && ctx.is_mouse_down(BTN_LEFT)) {
+		*value = calc_value(content_bounds.y, m.y, content_bounds.h, hh);
+		elem.slider.handle.y = calc_slider(content_bounds.y, content_bounds.h-hh, *value);
+		elem.events.update = true;
+	}
+
+	// Draw the slider background and handle
+	Style s = *style;
+	Rect padding = s.padding;
+	s.padding = {};
+	ctx.push_rect(elem.bounds, parent.div.z_index, &s)!;
+	s.bg = s.primary;
+	s.padding = padding;
+	s.border = {};
+	ctx.push_rect(elem.slider.handle, parent.div.z_index, &s)!;
+
+	return elem.events;
+}
+
+macro short calc_slider(short off, short dim, float value) => (short)off + (short)(dim * value);
+macro float calc_value(short off, short mouse, short dim, short slider)
+	=> math::clamp((float)(mouse-off-slider/2)/(float)(dim-slider), 0.0f, 1.0f);

lib/ugui.c3l/src/ugui_sprite.c3

@@ -0,0 +1,153 @@
+module ugui;
+
+import std::core::mem::allocator;
+import std::collections::map;
+import std::io;
+import std::compression::qoi;
+
+const usz SRITES_PER_ATLAS = 64;
+
+enum SpriteType {
+	SPRITE_NORMAL,
+	SPRITE_SDF,
+	SPRITE_MSDF,
+	SPRITE_ANIMATED,
+}
+
+struct Sprite {
+	Id id;
+	SpriteType type;
+	ushort u, v;
+	ushort w, h;
+}
+
+alias SpriteMap = map::HashMap{Id, Sprite};
+
+struct SpriteAtlas {
+	Id id;
+	Atlas atlas;
+	SpriteMap sprites;
+	bool should_update;
+}
+
+struct ElemSprite {
+	Id id;
+}
+
+// name: some examples are "icons" or "images"
+fn void? SpriteAtlas.init(&this, String name, AtlasType type, ushort width, ushort height)
+{
+	// FIXME: for now only R8G8B8A8 format is supported
+	if (type != ATLAS_R8G8B8A8) {
+		return INVALID_TYPE?;
+	}
+
+	this.id = name.hash();
+	this.atlas.new(this.id, AtlasType.ATLAS_R8G8B8A8, width, height)!;
+	this.sprites.init(allocator::heap(), capacity: SRITES_PER_ATLAS);
+	this.should_update = false;
+}
+
+fn void? SpriteAtlas.free(&this)
+{
+	this.atlas.free();
+	this.sprites.free();
+}
+
+// FIXME: this should throw an error when a different pixel format than the atlas' is used
+//        or convert from the source's pixel format to the atlas'
+fn Sprite*? SpriteAtlas.insert(&this, String name, SpriteType type, char[] pixels, ushort w, ushort h, ushort stride)
+{
+	Sprite s;
+	s.id = name.hash();
+	s.type = type;
+	Point uv = this.atlas.place(pixels, w, h, stride)!;
+	s.w = w;
+	s.h = h;
+	s.u = uv.x;
+	s.v = uv.y;
+	this.sprites.set(s.id, s);
+	this.should_update = true;
+	return this.sprites.get_ref(s.id);
+}
+
+fn Sprite*? SpriteAtlas.get(&this, String name)
+{
+	Id id = name.hash();
+	return this.sprites.get_ref(id);
+}
+
+fn Sprite*? SpriteAtlas.get_by_id(&this, Id id)
+{
+	return this.sprites.get_ref(id);
+}
+
+macro Rect Sprite.rect(s) => {0,0,s.w,s.h};
+macro Rect Sprite.uv(s) => {s.u,s.v,s.w,s.h};
+
+fn void? Ctx.sprite_atlas_create(&ctx, String name, AtlasType type, ushort w, ushort h)
+{
+	ctx.sprite_atlas.init(name, type, w, h)!;
+}
+
+fn Id Ctx.get_sprite_atlas_id(&ctx, String name)
+{
+	return name.hash();
+}
+
+fn void? Ctx.import_sprite_memory(&ctx, String name, char[] pixels, ushort w, ushort h, ushort stride, SpriteType type = SPRITE_NORMAL)
+{
+	ctx.sprite_atlas.insert(name, type, pixels, w, h, stride)!;
+}
+
+fn void? Ctx.import_sprite_file_qoi(&ctx, String name, String path, SpriteType type = SPRITE_NORMAL)
+{
+	QOIDesc desc;
+
+	char[] pixels = qoi::read(allocator::heap(), path, &desc, QOIChannels.RGBA)!;
+	defer mem::free(pixels);
+
+	ctx.sprite_atlas.insert(name, type, pixels, (ushort)desc.width, (ushort)desc.height, (ushort)desc.width)!;
+}
+
+
+macro Ctx.sprite(&ctx, String name, Point off = {0,0}, ...)
+	=> ctx.sprite_id(@compute_id($vasplat), name, off);
+fn void? Ctx.sprite_id(&ctx, Id id, String name, Point off)
+{
+	id = ctx.gen_id(id)!;
+
+	Elem *parent = ctx.get_parent()!;
+	Elem *elem = ctx.get_elem(id, ETYPE_SPRITE)!;
+
+	Style* style = ctx.styles.get_style(@str_hash("sprite"));
+	Sprite* sprite = ctx.sprite_atlas.get(name)!;
+
+	Rect uv = { sprite.u, sprite.v, sprite.w, sprite.h };
+	Rect bounds = { 0, 0, sprite.w, sprite.h };
+
+	elem.bounds = ctx.layout_element(parent, bounds.off(off), style);
+	elem.sprite.id = ctx.get_sprite_atlas_id(name);
+
+	// if the bounds are null the element is outside the div view,
+	//  no interaction should occur so just return
+	if (elem.bounds.is_null()) return;
+
+	Id tex_id = ctx.sprite_atlas.id;
+
+	return ctx.push_sprite(elem.bounds, uv, tex_id, parent.div.z_index)!;
+}
+
+fn void? Ctx.draw_sprite_raw(&ctx, String name, Rect bounds, bool center = false)
+{
+	Elem *parent = ctx.get_parent()!;
+	Sprite* sprite = ctx.sprite_atlas.get(name)!;
+	Id tex_id = ctx.sprite_atlas.id;
+	
+	if (center) {
+		Point off = {.x = (bounds.w - sprite.w) / 2, .y = (bounds.h - sprite.h) / 2};
+		bounds = bounds.off(off);
+	}
+	
+	return ctx.push_sprite(bounds, sprite.uv(), tex_id, parent.div.z_index, type: sprite.type)!;
+}

lib/ugui.c3l/src/ugui_style.c3

@@ -0,0 +1,436 @@
+module ugui;
+
+import std::collections::map;
+import std::core::mem::allocator;
+import std::io;
+
+// global style, similar to the css box model
+struct Style { // css box model
+	Rect  padding;
+	Rect  border;
+	Rect  margin;
+
+	Color bg;        // background color
+	Color fg;        // foreground color
+	Color primary;   // primary color
+	Color secondary; // secondary color
+	Color accent;    // accent color
+
+	ushort radius;
+	short  size;
+}
+
+const Style DEFAULT_STYLE = {
+	.margin  = {2, 2, 2, 2},
+	.border  = {2, 2, 2, 2},
+	.padding = {1, 1, 1, 1},
+	.radius  = 12,
+	.size    = 16,
+	
+	.bg = 0x282828ffu.@to_rgba(),
+	.fg = 0xfbf1c7ffu.@to_rgba(),
+	.primary = 0xcc241dffu.@to_rgba(),
+	.secondary = 0x458588ffu.@to_rgba(),
+	.accent = 0xfabd2fffu.@to_rgba(),
+};
+
+// style is stored in a hashmap, each style has an Id that can be generated by a string or whatever
+alias StyleMap = map::HashMap{Id, Style};
+
+// push or update a new style into the map
+fn void StyleMap.register_style(&map, Style* style, Id id)
+{
+	if (style == null) return;
+	map.set(id, *style);
+}
+
+// get a style from the map, if the style is not found then use a default style.
+fn Style* StyleMap.get_style(&map, Id id)
+{
+	Style*? s = map.get_ref(id);
+	if (catch s) {
+//		io::eprintfn("WARNING: style %x not found, using default style", id);
+		return &DEFAULT_STYLE;
+	}
+	return s;
+}
+
+fn int StyleMap.import_style_string(&map, String text)
+{
+	Parser p;
+	p.lex.text = text;
+	int added;
+	
+	while (p.parse_style() == true) {
+		added++;
+		// set the default style correctly
+		map.register_style(&p.style, p.style_id);
+		if (p.lex.peep_token().type == EOF) break;
+	}
+
+	return added;
+}
+
+fn int Ctx.import_style_from_string(&ctx, String text) => ctx.styles.import_style_string(text);
+fn int Ctx.import_style_from_file(&ctx, String path)
+{
+	char[] text;
+	usz size = file::get_size(path)!!;
+	text = mem::new_array(char, size);
+	file::load_buffer(path, text)!!;
+	defer mem::free(text);
+	
+	int added = ctx.import_style_from_string((String)text);
+	return added;
+}
+
+
+/*
+ * Style can be serialized and deserialized with a subset of CSS
+ * <style name> {
+ *     padding: left right top bottom;
+ *     border: left right top bottom;
+ *     margin: left right top bottoms;
+ *     radius: uint;
+ *     size: uint;
+ *     Color: #RRGGBBAA;
+ *     Color: #RRGGBBAA;
+ *     Color: #RRGGBBAA;
+ *     Color: #RRGGBBAA;
+ *     Color: #RRGGBBAA;
+ * }
+ * The field "style name" will be hashed and the hash used as the id int the style map.
+ * Fields may be excluded, each excluded field is set to zero.
+ * The default unit is pixels, but millimeters is also available. The parser function accepts a scale
+ * factor that has to be obtained with the window manager functions. 
+*/
+
+module ugui::css;
+
+import std::ascii;
+import std::io;
+
+// CSS parser module
+
+enum TokenType {
+	INVALID,
+	IDENTIFIER,
+	RCURLY,
+	LCURLY,
+	SEMICOLON,
+	COLON,
+	NUMBER,
+	COLOR,
+	EOF,
+}
+
+enum Unit {
+	PIXELS,
+	MILLIMETERS
+}
+
+struct Token {
+	TokenType type;
+	usz line, col, off;
+	String text;
+	union {
+		struct {
+			float value;
+			Unit unit;
+		}
+		Color color;
+	}
+}
+
+fn short Token.to_px(&t, float mm_to_px)
+{
+	if (t.type != NUMBER) {
+		unreachable("WFT you cannot convert to pixels a non-number");
+	}
+	if (t.unit == PIXELS) return (short)(t.value);
+	return (short)(t.value * mm_to_px);
+}
+
+struct Lexer {
+	String text;
+	usz line, col, off;
+}
+
+macro char Lexer.peep(&lex) => lex.text[lex.off];
+
+fn char Lexer.advance(&lex)
+{
+	if (lex.off >= lex.text.len) return '\0';
+
+	char c = lex.text[lex.off];
+	if (c == '\n') {
+		lex.col = 0;
+		lex.line++;
+	} else {
+		lex.col++;
+	}
+	lex.off++;
+	return c;
+}
+
+fn Token Lexer.next_token(&lex)
+{
+	Token t;
+	t.type = INVALID;
+	t.off = lex.off;
+	t.col = lex.col;
+	t.line = lex.line;
+
+	if (lex.off >= lex.text.len) {
+		return {.type = EOF};
+	}
+
+	// skip whitespace
+	while (ascii::is_space_m(lex.peep())) {
+		if (lex.advance() == 0) return {.type = EOF};
+		if (lex.off >= lex.text.len) return {.type = EOF}; 
+	}
+	t.off = lex.off;
+
+	switch (true) {
+	case ascii::is_punct_m(lex.peep()) && lex.peep() != '#': // punctuation
+		t.text = lex.text[lex.off:1];
+		if (lex.advance() == 0) { t.type = INVALID; break; }
+		switch (t.text[0]) {
+		case ':': t.type = COLON;
+		case ';': t.type = SEMICOLON;
+		case '{': t.type = LCURLY;
+		case '}': t.type = RCURLY;
+		default:  t.type = INVALID;
+		}
+
+	case lex.peep() == '#': // color
+		t.type = COLOR;
+		if (lex.advance() == 0) { t.type = INVALID; break; }
+		usz hex_start = t.off+1;
+		while (ascii::is_alnum_m(lex.peep())) {
+			if (lex.advance() == 0) { t.type = INVALID; break; }
+		}
+		if (lex.off - hex_start != 8) {
+			io::eprintfn("CSS lexing error at %d:%d: the only suppported color format is #RRGGBBAA", t.line, t.col);
+			t.type = INVALID;
+			break;
+		}
+		
+		char[10] hex_str = (char[])"0x";
+		hex_str[2..] = lex.text[hex_start..lex.off-1];
+		uint? color_hex = ((String)hex_str[..]).to_uint();
+		if (catch color_hex) {
+			t.type = INVALID;
+			break;
+		}
+		t.color = color_hex.to_rgba();
+	
+	case ascii::is_alpha_m(lex.peep()): // identifier
+		t.type = IDENTIFIER;
+		while (ascii::is_alnum_m(lex.peep()) || lex.peep() == '-' || lex.peep() == '_') {
+			if (lex.advance() == 0) { t.type = INVALID; break; }
+		}
+		t.text = lex.text[t.off..lex.off-1];
+	
+	case ascii::is_digit_m(lex.peep()): // number
+		t.type = NUMBER;
+		t.unit = PIXELS;
+		// find the end of the number
+		usz end;
+		while (ascii::is_alnum_m(lex.peep()) || lex.peep() == '+' || lex.peep() == '-' || lex.peep() == '.') {
+			if (lex.advance() == 0) { t.type = INVALID; break; } 
+		}
+		end = lex.off;
+		if (end - t.off > 2) {
+			if (lex.text[end-2:2] == "px") {
+				t.unit = PIXELS;
+				end -= 2;
+			} else if (lex.text[end-2:2] == "mm") {
+				t.unit = MILLIMETERS;
+				end -= 2;
+			} else if (lex.text[end-2:2] == "pt" || lex.text[end-2:2] == "em") {
+				io::eprintn("units 'em' or 'pt' are not supported at the moment");
+				t.type = INVALID;
+				break;
+			}
+		}
+		String number_str = lex.text[t.off..end-1];
+		float? value = number_str.to_float();
+		if (catch value) { t.type = INVALID; break; }
+		t.value = value;
+		t.text = lex.text[t.off..lex.off-1];
+	}
+	
+	if (t.type == INVALID) {
+		io::eprintfn("CSS Lexing ERROR at %d:%d: '%s' is not a valid token", t.line, t.col, lex.text[t.off..lex.off]);
+	}
+	return t;
+}
+
+fn Token Lexer.peep_token(&lex)
+{
+	Lexer start_state = *lex;
+	Token t;
+	t = lex.next_token();
+	*lex = start_state;
+	return t;
+}
+
+
+struct Parser {
+	Lexer lex;
+	Style style;
+	Id style_id;
+	float mm_to_px;
+}
+
+macro bool Parser.expect(&p, Token* t, TokenType type)
+{
+	*t = p.lex.next_token();
+	if (t.type == type) return true; 
+	io::eprintfn("CSS parsing error at %d:%d: expected %s but got %s", t.line, t.col, type, t.type);
+	return false;
+}
+
+fn bool Parser.parse_style(&p)
+{
+	Token t;
+	p.style = {};
+	p.style_id = 0;
+	
+	// style name
+	if (p.expect(&t, IDENTIFIER) == false) return false;
+	p.style_id = t.text.hash();
+
+	// style body
+	if (p.expect(&t, LCURLY) == false) return false;
+	
+	while (true) {
+		if (p.parse_property() == false) return false;
+		t = p.lex.peep_token();
+		if (t.type != IDENTIFIER) break;
+	}
+	
+	if (p.expect(&t, RCURLY) == false) return false;
+	
+	return true;
+}
+
+fn bool Parser.parse_property(&p)
+{
+	Token t, prop;
+	if (p.expect(&prop, IDENTIFIER) == false) return false;
+	if (p.expect(&t, COLON) == false) return false;
+
+	switch (prop.text) {
+	case "padding":
+		Rect padding;
+		if (p.parse_size(&padding) == false) return false;
+		p.style.padding = padding;
+
+	case "border":
+		Rect border;
+		if (p.parse_size(&border) == false) return false;
+		p.style.border = border;
+
+	case "margin":
+		Rect margin;
+		if (p.parse_size(&margin) == false) return false;
+		p.style.margin = margin;
+
+	case "bg":
+		Color bg;
+		if (p.parse_color(&bg) == false) return false;
+		p.style.bg = bg;
+
+	case "fg":
+		Color fg;
+		if (p.parse_color(&fg) == false) return false;
+		p.style.fg = fg;
+
+	case "primary":
+		Color primary;
+		if (p.parse_color(&primary) == false) return false;
+		p.style.primary = primary;
+
+	case "secondary":
+		Color secondary;
+		if (p.parse_color(&secondary) == false) return false;
+		p.style.secondary = secondary;
+
+	case "accent":
+		Color accent;
+		if (p.parse_color(&accent) == false) return false;
+		p.style.accent = accent;
+
+	case "radius":
+		short r;
+		if (p.parse_number(&r) == false) return false;
+		if (r < 0) {
+			io::eprintfn("CSS parsing error at %d:%d: 'radius' must be a positive number, got %d", t.line, t.col, r);
+			return false;
+		}
+		p.style.radius = (ushort)r;
+		
+	case "size":
+		short s;
+		if (p.parse_number(&s) == false) return false;
+		if (s < 0) {
+			io::eprintfn("CSS parsing error at %d:%d: 'size' must be a positive number, got %d", t.line, t.col, s);
+			return false;
+		}
+		p.style.size = (ushort)s;
+
+
+	default:
+		io::eprintfn("CSS parsing error at %d:%d: '%s' is not a valid property", prop.line, prop.col, prop.text);
+		return false;
+	}
+	if (p.expect(&t, SEMICOLON) == false) return false;
+	return true;
+}
+
+fn bool Parser.parse_number(&p, short* n)
+{
+	Token t;
+	if (p.expect(&t, NUMBER) == false) return false;
+	*n = t.to_px(p.mm_to_px);
+	return true;
+}
+
+// FIXME: since '#' is punctuation this cannot be done in parsing but it has to be done in lexing
+fn bool Parser.parse_color(&p, Color* c)
+{
+	Token t;
+	if (p.expect(&t, COLOR) == false) return false;
+	*c = t.color;
+	return true;
+}
+
+fn bool Parser.parse_size(&p, Rect* r)
+{
+	short x;
+	Token t;
+	
+	if (p.parse_number(&x) == false) return false;
+	
+	t = p.lex.peep_token();
+	if (t.type == NUMBER) {
+		// we got another number so we expect three more
+		r.x = x;
+		if (p.parse_number(&x) == false) return false;
+		r.y = x;
+		if (p.parse_number(&x) == false) return false;
+		r.w = x;
+		if (p.parse_number(&x) == false) return false;
+		r.h = x;
+		return true;
+	} else if (t.type == SEMICOLON) {
+		// just one number, all dimensions are the same
+		r.x = r.y = r.w = r.h = x;
+		return true;
+	}
+
+	return false;
+}

lib/ugui.c3l/src/ugui_text.c3

@@ -0,0 +1,79 @@
+module ugui;
+
+import std::io;
+
+struct ElemText {
+	String str;
+	usz cursor; // cursor offset
+	Id hash;
+	Rect bounds;
+}
+
+macro Ctx.text_unbounded(&ctx, String text, ...)
+	=> ctx.text_unbounded_id(@compute_id($vasplat), text);
+fn void? Ctx.text_unbounded_id(&ctx, Id id, String text)
+{
+	id = ctx.gen_id(id)!;
+
+	Elem *parent = ctx.get_parent()!;
+	Elem *elem = ctx.get_elem(id, ETYPE_TEXT)!;
+	Style* style = ctx.styles.get_style(@str_hash("text"));
+
+	Id text_hash = text.hash();
+	if (elem.flags.is_new || elem.text.hash != text_hash) {
+		elem.text.bounds = ctx.get_text_bounds(text)!;
+	}
+	elem.text.str = text;
+	elem.text.hash = text_hash;
+
+	// 2. Layout
+	elem.bounds = ctx.layout_element(parent, elem.text.bounds, style);
+	if (elem.bounds.is_null()) { return; }
+
+	ctx.push_string(elem.bounds, text, parent.div.z_index, style.fg)!;
+}
+
+macro Ctx.text_box(&ctx, Rect size, char[] text, usz* text_len, ...)
+	=> ctx.text_box_id(@compute_id($vasplat), size, text, text_len);
+fn ElemEvents? Ctx.text_box_id(&ctx, Id id, Rect size, char[] text, usz* text_len)
+{
+	id = ctx.gen_id(id)!;
+
+	Elem *parent = ctx.get_parent()!;
+	Elem *elem = ctx.get_elem(id, ETYPE_TEXT)!;
+	Style* style = ctx.styles.get_style(@str_hash("text-box"));
+
+	elem.text.str = (String)text;
+	
+	// layout the text box
+	elem.bounds = ctx.layout_element(parent, size, style);
+
+	// check input and update the text
+	elem.events = ctx.get_elem_events(elem);
+	
+	if (elem.events.text_input) {
+		usz l = ctx.input.keyboard.text_len;
+		char[] t = ctx.input.keyboard.text[..l];
+				
+		if (l != 0 && l < text.len - *text_len) {
+			text[*text_len..*text_len+l] = t[..];
+			*text_len += l;
+		}
+		
+		if (ctx.input.keyboard.modkeys.bkspc) {
+			*text_len = *text_len > 0 ? *text_len-1 : 0;
+		}
+		
+	}
+	elem.text.cursor = *text_len;
+
+	// draw the box
+	short line_height = (short)ctx.font.line_height();
+	Rect text_box = elem.bounds;
+	ctx.push_rect(text_box, parent.div.z_index, style)!;
+	ctx.push_string(text_box, text[:*text_len], parent.div.z_index, style.fg, true)!;
+	
+	// TODO: draw cursor
+
+	return elem.events;
+}

lib/ugui.c3l/src/vtree.c3

@@ -1,4 +1,7 @@
-module vtree(<ElemType>);
+module vtree::faults;
+faultdef CANNOT_SHRINK, INVALID_REFERENCE, TREE_FULL, REFERENCE_NOT_PRESENT, INVALID_ARGUMENT;
+
+module vtree{ElemType};
 
 import std::core::mem;
 import std::io;
@@ -9,13 +12,6 @@ struct VTree {
 	isz[] refs, ordered_refs;
 }
 
-fault VTreeError {
-	CANNOT_SHRINK,
-	INVALID_REFERENCE,
-	TREE_FULL,
-	REFERENCE_NOT_PRESENT,
-	INVALID_ARGUMENT,
-}
 
 macro VTree.ref_is_valid(&tree, isz ref) { return (ref >= 0 && ref < tree.refs.len); }
 macro VTree.ref_is_present(&tree, isz ref) { return tree.refs[ref] >= 0; }
@@ -27,11 +23,11 @@ macro @zero()
 	$if $assignable(0, ElemType):
 		return 0;
 	$else
-		return ElemType{0};
+		return {};
 	$endif
 }
 
-fn void! VTree.init(&tree, usz size)
+fn void? VTree.init(&tree, usz size)
 {
 	tree.vector = mem::new_array(ElemType, size);
 	defer catch { (void)mem::free(tree.vector); }
@@ -74,7 +70,7 @@ fn void VTree.pack(&tree)
 			tree.vector[free_spot] = tree.vector[i];
 			tree.refs[free_spot]   = tree.refs[i];
 
-			tree.vector[i] = @zero();
+			tree.vector[i] = {};
 			tree.refs[i]   = -1;
 
 			// and move all references
@@ -90,18 +86,18 @@ fn void VTree.pack(&tree)
 	}
 }
 
-fn void! VTree.resize(&tree, usz newsize)
+fn void? VTree.resize(&tree, usz newsize)
 {
 	// return error when shrinking with too many elements
 	if (newsize < tree.elements) {
-		return VTreeError.CANNOT_SHRINK?;
+		return vtree::faults::CANNOT_SHRINK?;
 	}
 
 	// pack the vector when shrinking to avoid data loss
 	if ((int)newsize < tree.size()) {
 		// FIXME: packing destroys all references to elements of vec
 		//        so shrinking may cause dangling pointers
-		return VTreeError.CANNOT_SHRINK?;
+		return vtree::faults::CANNOT_SHRINK?;
 	}
 
 	usz old_size = tree.size();
@@ -122,22 +118,22 @@ fn void! VTree.resize(&tree, usz newsize)
 }
 
 // add an element to the tree, return it's ref
-fn isz! VTree.add(&tree, ElemType elem, isz parent)
+fn isz? VTree.add(&tree, ElemType elem, isz parent)
 {
 	// invalid parent
 	if (!tree.ref_is_valid(parent)) {
-		return VTreeError.INVALID_REFERENCE?;
+		return vtree::faults::INVALID_REFERENCE?;
 	}
 
 	// no space left
 	if (tree.elements >= tree.size()) {
-		return VTreeError.TREE_FULL?;
+		return vtree::faults::TREE_FULL?;
 	}
 
 	// check if the parent exists
 	// if there are no elements in the tree the first add will set the root
 	if (!tree.ref_is_present(parent) && tree.elements != 0) {
-		return VTreeError.REFERENCE_NOT_PRESENT?;
+		return vtree::faults::REFERENCE_NOT_PRESENT?;
 	}
 
 	// get the first free spot
@@ -149,7 +145,7 @@ fn isz! VTree.add(&tree, ElemType elem, isz parent)
 		}
 	}
 	if (free_spot < 0) {
-		return VTreeError.TREE_FULL?;
+		return vtree::faults::TREE_FULL?;
 	}
 
 	// finally add the element
@@ -162,10 +158,10 @@ fn isz! VTree.add(&tree, ElemType elem, isz parent)
 
 // prune the tree starting from the ref
 // returns the number of pruned elements
-fn usz! VTree.prune(&tree, isz ref)
+fn usz? VTree.prune(&tree, isz ref)
 {
 	if (!tree.ref_is_valid(ref)) {
-		return VTreeError.INVALID_REFERENCE?;
+		return vtree::faults::INVALID_REFERENCE?;
 	}
 
 	if (!tree.ref_is_present(ref)) {
@@ -186,11 +182,20 @@ fn usz! VTree.prune(&tree, isz ref)
 	return count;
 }
 
+fn usz VTree.nuke(&tree)
+{
+	tree.vector[0..] = @zero();
+	tree.refs[0..] = -1;
+	usz x = tree.elements;
+	tree.elements = 0;
+	return x;
+}
+
 // find the size of the subtree starting from ref
-fn usz! VTree.subtree_size(&tree, isz ref)
+fn usz? VTree.subtree_size(&tree, isz ref)
 {
 	if (!tree.ref_is_valid(ref)) {
-		return VTreeError.INVALID_REFERENCE?;
+		return vtree::faults::INVALID_REFERENCE?;
 	}
 
 	if (!tree.ref_is_present(ref)) {
@@ -209,20 +214,20 @@ fn usz! VTree.subtree_size(&tree, isz ref)
 }
 
 // iterate through the first level children, use a cursor like strtok_r
-fn isz! VTree.children_it(&tree, isz parent, isz *cursor)
+fn isz? VTree.children_it(&tree, isz parent, isz *cursor)
 {
 	if (cursor == null) {
-		return VTreeError.INVALID_ARGUMENT?;
+		return vtree::faults::INVALID_ARGUMENT?;
 	}
 
 	// if the cursor is out of bounds then we are done for sure
 	if (!tree.ref_is_valid(*cursor)) {
-		return VTreeError.INVALID_REFERENCE?;
+		return vtree::faults::INVALID_REFERENCE?;
 	}
 
 	// same for the parent, if it's invalid it can't have children
 	if (!tree.ref_is_valid(parent) || !tree.ref_is_present(parent)) {
-		return VTreeError.INVALID_REFERENCE?;
+		return vtree::faults::INVALID_REFERENCE?;
 	}
 
 	// find the first child, update the cursor and return the ref
@@ -247,10 +252,10 @@ fn isz! VTree.children_it(&tree, isz parent, isz *cursor)
  *         /   \    [6]
  *       [4]   [5]
  */
-fn isz! VTree.level_order_it(&tree, isz ref, isz *cursor)
+fn isz? VTree.level_order_it(&tree, isz ref, isz *cursor)
 {
 	if (cursor == null) {
-		return VTreeError.INVALID_ARGUMENT?;
+		return vtree::faults::INVALID_ARGUMENT?;
 	}
 
 	isz[] queue = tree.ordered_refs;
@@ -294,27 +299,27 @@ fn isz! VTree.level_order_it(&tree, isz ref, isz *cursor)
 	return -1;
 }
 
-fn isz! VTree.parentof(&tree, isz ref)
+fn isz? VTree.parentof(&tree, isz ref)
 {
 	if (!tree.ref_is_valid(ref)) {
-		return VTreeError.INVALID_REFERENCE?;
+		return vtree::faults::INVALID_REFERENCE?;
 	}
 
 	if (!tree.ref_is_present(ref)) {
-		return VTreeError.REFERENCE_NOT_PRESENT?;
+		return vtree::faults::REFERENCE_NOT_PRESENT?;
 	}
 
 	return tree.refs[ref];
 }
 
-fn ElemType! VTree.get(&tree, isz ref)
+fn ElemType? VTree.get(&tree, isz ref)
 {
 	if (!tree.ref_is_valid(ref)) {
-		return VTreeError.INVALID_REFERENCE?;
+		return vtree::faults::INVALID_REFERENCE?;
 	}
 
 	if (!tree.ref_is_present(ref)) {
-		return VTreeError.REFERENCE_NOT_PRESENT?;
+		return vtree::faults::REFERENCE_NOT_PRESENT?;
 	}
 
 	return tree.vector[ref];

lib/vendor

@@ -0,0 +1 @@
+Subproject commit db006221a8af625630fdb8b56707f3d07d4314a2

project.json

@@ -1,55 +1,20 @@
 {
-  // Language version of C3.
   "langrev": "1",
-  // Warnings used for all targets.
-  "warnings": [ "no-unused" ],
-  // Directories where C3 library files may be found.
-  "dependency-search-paths": [ "lib" ],
-  // Libraries to use for all targets.
-  "dependencies": [ "raylib", "schrift", "grapheme" ],
-  "features": [
-    // See rcore.c3
-    //"SUPPORT_INTERNAL_MEMORY_MANAGEMENT",
-    //"SUPPORT_STANDARD_FILEIO",
-    //"SUPPORT_FILE_SYSTEM_FUNCTIONS",
-    //"SUPPORT_DATA_ENCODER",
-    // See text.c3
-    //"SUPPORT_TEXT_CODEPOINTS_MANAGEMENT",
-    //"SUPPORT_TEXT_C_STRING_MANAGEMENT",
-    //"SUPPORT_RANDOM_GENERATION",
-    //"SUPPORT_RAYGUI",
-    //"RAYGUI_NO_ICONS",
-    //"RAYGUI_CUSTOM_ICONS",
-  ],
-  // Authors, optionally with email.
-  "authors": [ "John Doe <ale@shitposting.expert>" ],
-  // Version using semantic versioning.
+  "warnings": ["no-unused"],
+  "dependency-search-paths": ["lib", "lib/vendor/libraries"],
+  "dependencies": ["sdl3", "ugui"],
+  "features": [],
+  "authors": ["Alessandro Mauri <ale@shitposting.expert>"],
   "version": "0.1.0",
-  // Sources compiled for all targets.
-  "sources": [ "src/**" ],
-  // C sources if the project also compiles C sources
-  // relative to the project file.
-  // "c-sources": [ "csource/**" ],
-  // Include directories for C sources relative to the project file.
-  // "c-include-dirs": [ "csource/include" ],
-  // Output location, relative to project file.
+  "sources": ["src/**"],
   "output": "build",
-  // Architecture and OS target.
-  // You can use 'c3c --list-targets' to list all valid targets.
-  // "target": "windows-x64",
-  // Targets.
+  "target": "linux-x64",
   "targets": {
     "ugui": {
-      // Executable or library.
-      "type": "executable",
-      // Additional libraries, sources
-      // and overrides of global settings here.
+      "type": "executable"
+    }
   },
-  },
-  // Global settings.
-  // CPU name, used for optimizations in the LLVM backend.
-  "cpu": "generic",
-  // Optimization: "O0", "O1", "O2", "O3", "O4", "O5", "Os", "Oz".
+  "cpu": "native",
   "opt": "O0",
-  // See resources/examples/project_all_settings.json and 'c3c --list-project-properties' to see more properties.
+  "debug-info": "full"
 }

resources/shaders/Makefile

@@ -0,0 +1,33 @@
+SOURCE_DIR := ./source
+COMPILED_DIR := ./compiled
+
+SOURCE_FILES := $(wildcard $(SOURCE_DIR)/*.glsl)
+
+COMPILED_FILES := $(patsubst $(SOURCE_DIR)/%.glsl,$(COMPILED_DIR)/%.spv,$(SOURCE_FILES))
+
+all: $(COMPILED_FILES)
+	@echo "Compiling shaders from $(SOURCE_DIR) -> $(COMPILED_DIR)"
+
+$(COMPILED_DIR)/%.spv: $(SOURCE_DIR)/%.glsl
+	@mkdir -p $(COMPILED_DIR)
+	@stage=$$(basename $< .glsl | cut -d. -f2); \
+	if [ "$$stage" = "frag" ] || [ "$$stage" = "vert" ]; then \
+		echo "$$stage $(notdir $<) > $(notdir $@)"; \
+		glslc -O0 -g -fshader-stage=$$stage $< -o $@; \
+	else \
+		echo "Skipping $<: unsupported stage $$stage"; \
+	fi
+
+$(COMPILED_DIR):
+	mkdir -p $(COMPILED_DIR)
+
+.PHONY: clean
+clean:
+	rm -rf $(COMPILED_DIR)
+
+.PHONY: tree
+tree:
+	tree $(COMPILED_DIR)
+
+.PHONY: compile_all
+compile_all: clean all tree

resources/shaders/source/font.frag.glsl

@@ -0,0 +1,21 @@
+#version 450
+
+layout(set = 3, binding = 0) uniform Viewport {
+    ivec2 view;
+};
+layout(set = 2, binding = 0) uniform sampler2D tx;
+
+layout(location = 0) in vec2 uv;
+layout(location = 1) in vec4 color;
+
+layout(location = 0) out vec4 fragColor;
+
+void main()
+{
+    ivec2 ts = textureSize(tx, 0);
+    vec2 fts = vec2(ts);
+    vec2 real_uv = uv / fts;
+
+    vec4 opacity = texture(tx, real_uv);
+    fragColor = vec4(color.rgb, color.a*opacity.r);
+}

resources/shaders/source/msdf.frag.glsl

@@ -0,0 +1,35 @@
+#version 450
+
+layout(set = 3, binding = 0) uniform Viewport {
+    ivec2 view;
+};
+layout(set = 2, binding = 0) uniform sampler2D tx;
+
+const float PX_RANGE = 4.0f;
+
+layout(location = 0) in vec2 uv;
+layout(location = 1) in vec4 color;
+
+layout(location = 0) out vec4 fragColor;
+
+float screen_px_range(vec2 uv) {
+    vec2 unit_range = vec2(PX_RANGE)/vec2(textureSize(tx, 0));
+    vec2 texel_size = vec2(1.0)/fwidth(uv);
+    return max(0.5*dot(unit_range, texel_size), 1.0);
+}
+
+float median(float r, float g, float b) {
+	return max(min(r, g), min(max(r, g), b));
+}
+
+void main() {
+    ivec2 ts = textureSize(tx, 0);
+    vec2 fts = vec2(ts);
+    vec2 real_uv = uv / fts;
+
+	vec3 msd = texture(tx, real_uv).rgb;
+	float sd = median(msd.r, msd.g, msd.b);
+	float distance = screen_px_range(real_uv)*(sd - 0.5);
+	float opacity = clamp(distance + 0.5, 0.0, 1.0);
+	fragColor = color * opacity;
+}

resources/shaders/source/rect.frag.glsl

@@ -0,0 +1,27 @@
+#version 450
+
+layout(set = 3, binding = 0) uniform Viewport {
+    ivec2 view;
+};
+
+layout(location = 0) in vec4 in_color;
+layout(location = 1) in vec4 in_quad_size; // x,y, w,h
+layout(location = 2) in float in_radius;
+
+layout(location = 0) out vec4 fragColor;
+
+// SDF for a rounded rectangle given the centerpoint, half size and radius, all in pixels
+float sdf_rr(vec2 p, vec2 half_size, float radius) {
+    vec2 q = abs(p) - half_size + radius;
+    return length(max(q, 0.0)) + min(max(q.x, q.y), 0.0) - radius;
+}
+
+void main()
+{
+    vec2 centerpoint = in_quad_size.xy + in_quad_size.zw * 0.5;
+    vec2 half_size = in_quad_size.zw * 0.5;
+    float distance = sdf_rr(vec2(gl_FragCoord) - centerpoint, half_size, in_radius);
+    float alpha = 1.0 - smoothstep(0.0, 1.5, distance);
+
+    fragColor = vec4(in_color.rgb, in_color.a * alpha);
+}

resources/shaders/source/rect.vert.glsl

@@ -0,0 +1,29 @@
+#version 450
+
+layout(set = 1, binding = 0) uniform Viewport {
+	ivec2 view;
+};
+
+layout(location = 0) in ivec2 position;
+layout(location = 1) in ivec4 attr; // quad x,y,w,h
+layout(location = 2) in ivec2 uv;   // x,y in the texture
+layout(location = 3) in uvec4 color;
+
+layout(location = 0) out vec4 out_color;
+layout(location = 1) out vec4 out_quad_size;
+layout(location = 2) out float out_radius;
+
+void main()
+{
+	// vertex position
+	ivec2 px_pos = attr.xy + position.xy * attr.zw;
+	vec2 clip_pos;
+	clip_pos.x = float(px_pos.x)*2.0 / view.x - 1.0;
+	clip_pos.y = -(float(px_pos.y)*2.0 / view.y - 1.0);
+
+	gl_Position = vec4(clip_pos, 0.0, 1.0);
+
+	out_color = vec4(color) / 255.0;
+	out_quad_size = vec4(attr);
+	out_radius = float(abs(uv.x));
+}

resources/shaders/source/sprite.frag.glsl

@@ -0,0 +1,18 @@
+#version 450
+
+layout(set = 3, binding = 0) uniform Viewport {
+    ivec2 view;
+};
+
+layout(location = 0) in vec2 uv;
+layout(location = 0) out vec4 fragColor;
+
+layout(set = 2, binding = 0) uniform sampler2D tx;
+
+void main()
+{
+    ivec2 ts = textureSize(tx, 0);
+    vec2 fts = vec2(ts);
+    vec2 real_uv = uv / fts;
+    fragColor = texture(tx, real_uv);
+}

resources/shaders/source/sprite.vert.glsl

@@ -0,0 +1,28 @@
+#version 450
+
+layout(set = 1, binding = 0) uniform Viewport {
+    ivec2 view;
+};
+
+layout(location = 0) in ivec2 position;
+layout(location = 1) in ivec4 attr; // quad x,y,w,h
+layout(location = 2) in ivec2 in_uv;
+layout(location = 3) in uvec4 color;
+
+layout(location = 0) out vec2 out_uv;
+layout(location = 1) out vec4 out_color;
+
+void main()
+{
+	// vertex position
+	ivec2 px_pos = attr.xy + position.xy * attr.zw;
+	vec2 clip_pos;
+	clip_pos.x = float(px_pos.x)*2.0 / view.x - 1.0;
+	clip_pos.y = -(float(px_pos.y)*2.0 / view.y - 1.0);
+
+	gl_Position = vec4(clip_pos, 0.0, 1.0);
+
+    vec2 px_uv = in_uv.xy + position.xy * attr.zw;
+    out_uv = vec2(px_uv);
+    out_color = vec4(color) / 255.0;
+}

resources/style.css

@@ -0,0 +1,61 @@
+default {
+	bg: #282828ff;
+	fg: #fbf1c7ff;
+	primary: #cc241dff;
+	secondary: #458588ff;
+	accent: #fabd2fff;
+	border: 1;
+}
+
+button {
+	margin: 2;
+	border: 2;
+	padding: 2;
+	radius: 10;
+	size: 32;
+
+	bg: #3c3836ff;
+	fg: #fbf1c7ff;
+	primary: #cc241dff;
+	secondary: #458588ff;
+	accent: #504945ff;
+}
+
+checkbox {
+	margin: 2;
+	border: 2;
+	padding: 1;
+	radius: 10;
+	size: 16;
+	bg: #3c3836ff;
+	fg: #fbf1c7ff;
+	primary: #cc241dff;
+	secondary: #458588ff;
+	accent: #fabd2fff;
+}
+
+toggle {
+	margin: 2;
+	border: 2;
+	padding: 1;
+	radius: 10;
+	size: 16;
+	bg: #3c3836ff;
+	fg: #fbf1c7ff;
+	primary: #cc241dff;
+	secondary: #458588ff;
+	accent: #fabd2fff;
+}
+
+slider {
+	margin: 2;
+	padding: 2;
+	border: 1;
+	radius: 4;
+	size: 8;
+	bg: #3c3836ff;
+	fg: #fbf1c7ff;
+	primary: #cc241dff;
+	secondary: #458588ff;
+	accent: #fabd2fff;
+}

src/fifo.c3

@@ -1,49 +0,0 @@
-module fifo(<Type>);
-
-import std::core::mem;
-
-fault FifoErr {
-	FULL,
-	EMPTY,
-}
-
-// TODO: specify the allocator
-
-struct Fifo {
-	Type[] arr;
-	usz out;
-	usz count;
-}
-
-fn void! Fifo.init(&fifo, usz size)
-{
-	fifo.arr = mem::new_array(Type, size);
-	fifo.out = 0;
-	fifo.count = 0;
-}
-
-fn void Fifo.free(&fifo)
-{
-	(void)mem::free(fifo.arr);
-}
-
-fn void! Fifo.enqueue(&fifo, Type *elem)
-{
-	if (fifo.count >= fifo.arr.len) {
-		return FifoErr.FULL?;
-	}
-	usz in = (fifo.out + fifo.count) % fifo.arr.len;
-	fifo.arr[in] = *elem;
-	fifo.count++;
-}
-
-fn Type*! Fifo.dequeue(&fifo)
-{
-	if (fifo.count == 0) {
-		return FifoErr.EMPTY?;
-	}
-	Type *ret = &fifo.arr[fifo.out];
-	fifo.count--;
-	fifo.out = (fifo.out + 1) % fifo.arr.len;
-	return ret;
-}

src/main.c3

@@ -2,11 +2,14 @@ import std::io;
 import vtree;
 import cache;
 import ugui;
-import rl;
 import std::time;
 import std::collections::ringbuffer;
+import std::core::string;
+import std::ascii;
+import sdlrenderer::ren;
+import sdl3::sdl;
 
-def Times = ringbuffer::RingBuffer(<time::NanoDuration, 128>);
+alias Times = ringbuffer::RingBuffer{time::NanoDuration[128]};
 
 fn void Times.print_stats(&times)
 {
@@ -23,216 +26,334 @@ fn void Times.print_stats(&times)
 	io::printfn("min=%s, max=%s, avg=%s", min, max, avg);
 }
 
+struct TimeStats {
+	time::NanoDuration min, max, avg;
+}
+
+fn TimeStats Times.get_stats(&times)
+{
+	time::NanoDuration min, max, avg, x;
+	min = times.get(0);
+	for (usz i = 0; i < times.written; i++) {
+		x = times.get(i);
+		if (x < min) { min = x; }
+		if (x > max) { max = x; }
+		avg += x;
+	}
+	avg = (NanoDuration)((ulong)avg/128.0);
+
+	return {.min = min, .max = max, .avg = avg};
+}
+
+
+const char[*] MSDF_FS_PATH = "resources/shaders/compiled/msdf.frag.spv";
+const char[*] SPRITE_FS_PATH = "resources/shaders/compiled/sprite.frag.spv";
+const char[*] FONT_FS_PATH = "resources/shaders/compiled/font.frag.spv";
+const char[*] RECT_FS_PATH = "resources/shaders/compiled/rect.frag.spv";
+
+const char[*] SPRITE_VS_PATH = "resources/shaders/compiled/sprite.vert.spv";
+const char[*] RECT_VS_PATH = "resources/shaders/compiled/rect.vert.spv";
+
+const char[*] STYLESHEET_PATH = "resources/style.css";
+
 fn int main(String[] args)
 {
 	ugui::Ctx ui;
 	ui.init()!!;
-	ui.font.load("/usr/share/fonts/TTF/HackNerdFontMono-Regular.ttf", 16)!!;
+	defer ui.free();
 
-	short width = 800;
-	short height = 450;
-	rl::set_config_flags(rl::FLAG_WINDOW_RESIZABLE);
-	rl::init_window(width, height, "Ugui Test");
-	ui.input_window_size(width, height)!!;
-	rl::set_target_fps(60);
-	rl::enable_event_waiting();
+	ren::Renderer ren;
+	ren.init("Ugui Test", 800, 600, true);
+	defer ren.free();
+	ui.input_window_size(800, 600)!!;
+
+	//
+	// FONT LOADING
+	//
+	{
+		// import font in the ui context
+		ui.load_font("font1", "resources/hack-nerd.ttf", 16)!!;
+		
+		// create the rendering pipeline
+		ren.font_atlas_id = ui.get_font_id("font1");
+		ren.load_spirv_shader_from_file("UGUI_PIPELINE_FONT", SPRITE_VS_PATH, FONT_FS_PATH, 1, 0);
+		ren.create_pipeline("UGUI_PIPELINE_FONT", SPRITE);
+		
+		// send the atlas to the gpu
+		Atlas* font_atlas = ui.get_font_atlas("font1")!!;
+		ren.new_texture("font1", JUST_ALPHA, font_atlas.buffer, font_atlas.width, font_atlas.height);
+	}
+
+	//
+	// ICON LOADING
+	//
+	{
+		// create the atlas and upload some icons
+		ui.sprite_atlas_create("icons", AtlasType.ATLAS_R8G8B8A8, 512, 512)!!;
+		ui.import_sprite_file_qoi("tux", "resources/tux.qoi")!!;
+		ui.import_sprite_file_qoi("tick", "resources/tick_sdf.qoi", SpriteType.SPRITE_MSDF)!!;
+		
+		// create the rendering pipelines
+		ren.sprite_atlas_id = ui.get_sprite_atlas_id("icons");
+		// normal sprite pipeline
+		ren.load_spirv_shader_from_file("UGUI_PIPELINE_SPRITE", SPRITE_VS_PATH, SPRITE_FS_PATH, 1, 0);
+		ren.create_pipeline("UGUI_PIPELINE_SPRITE", SPRITE);
+		// msdf sprite pipeline
+		ren.load_spirv_shader_from_file("UGUI_PIPELINE_SPRITE_MSDF", SPRITE_VS_PATH, MSDF_FS_PATH, 1, 0);
+		ren.create_pipeline("UGUI_PIPELINE_SPRITE_MSDF", SPRITE);
+	
+		// upload the atlas to the gpu
+		Atlas atlas = ui.sprite_atlas.atlas;
+		ren.new_texture("icons", FULL_COLOR, atlas.buffer, atlas.width, atlas.height);
+	}
+
+	//
+	// RECT PIPELINE
+	//
+	ren.load_spirv_shader_from_file("UGUI_PIPELINE_RECT", RECT_VS_PATH, RECT_FS_PATH, 0, 0);
+	ren.create_pipeline("UGUI_PIPELINE_RECT", RECT);
+
+
+	// CSS INPUT
+	io::printfn("imported %d styles", ui.import_style_from_file(STYLESHEET_PATH));
 
 	isz frame;
-	bool toggle = true;
+	double fps;
 	time::Clock clock;
+	time::Clock fps_clock;
+	time::Clock sleep_clock;
 	Times ui_times;
 	Times draw_times;
 
-	// Main loop
-	while (!rl::window_should_close()) {
-		clock.mark();
 
-		/* Start Input Handling */
-		if (rl::is_window_resized()) {
-			width  = (short)rl::get_screen_width();
-			height = (short)rl::get_screen_height();
-			ui.input_window_size(width, height)!!;
+	//
+	// MAIN LOOP
+	//
+	sdl::start_text_input(ren.win);
+
+	sdl::Event e;
+	bool quit = false;
+	ugui::ModKeys mod;
+	ugui::MouseButtons btn;
+	while (!quit) {
+		clock.mark();
+		fps_clock.mark();
+		sleep_clock.mark();
+		
+		do {
+			switch (e.type) {
+			case EVENT_QUIT: 
+				quit = true;
+			case EVENT_KEY_UP: nextcase;
+			case EVENT_KEY_DOWN:
+				mod.rctrl = e.key.key == K_RCTRL ? !!(e.type == EVENT_KEY_DOWN) : mod.rctrl;
+				mod.lctrl = e.key.key == K_LCTRL ? !!(e.type == EVENT_KEY_DOWN) : mod.lctrl;
+				mod.bkspc = e.key.key == K_BACKSPACE ? !!(e.type == EVENT_KEY_DOWN) : mod.bkspc;
+
+				// pressing ctrl+key or alt+key does not generate a character as such no 
+				// TEXT_INPUT event is generated. When those keys are pressed we have to 
+				// do manual text input, bummer
+				if (e.type == EVENT_KEY_DOWN && (mod.lctrl || mod.rctrl)) {
+					if (ascii::is_alnum_m((uint)e.key.key)) {
+						ui.input_char((char)e.key.key);
+					}
 				}
 				
-		ui.input_changefocus(rl::is_window_focused());
+				if (e.type == EVENT_KEY_DOWN && e.key.key == K_RETURN) ui.input_char('\n');
 
-		rl::Vector2 mpos = rl::get_mouse_position();
-		ui.input_mouse_abs((short)mpos.x, (short)mpos.y);
+			case EVENT_TEXT_INPUT:
+				ui.input_text_utf8(e.text.text.str_view());
+			case EVENT_WINDOW_RESIZED:
+				ui.input_window_size((short)e.window.data1, (short)e.window.data2)!!;
+			case EVENT_WINDOW_FOCUS_GAINED:
+				ui.input_changefocus(true);
+			case EVENT_WINDOW_FOCUS_LOST:
+				ui.input_changefocus(false);
+			case EVENT_MOUSE_MOTION:
+				ui.input_mouse_abs((short)e.motion.x, (short)e.motion.y);
+			case EVENT_MOUSE_WHEEL:
+				ui.input_mouse_wheel((short)e.wheel.integer_x, (short)e.wheel.integer_y);
+			case EVENT_MOUSE_BUTTON_DOWN: nextcase;
+			case EVENT_MOUSE_BUTTON_UP:
+				sdl::MouseButtonFlags mb = sdl::get_mouse_state(null, null);
+				btn = {
+					.btn_left = !!(mb & BUTTON_LMASK),
+					.btn_right = !!(mb & BUTTON_RMASK),
+					.btn_middle = !!(mb & BUTTON_MMASK),
+					.btn_4 = !!(mb & BUTTON_X1MASK),
+					.btn_5 = !!(mb & BUTTON_X2MASK),
+				};
+			case EVENT_POLL_SENTINEL: break;
+			default:
+				io::eprintfn("unhandled event: %s", e.type);
+			}
+		} while(sdl::poll_event(&e));
+		ui.input_mod_keys(mod);
+		ui.input_mouse_button(btn);
 
-		ugui::MouseButtons buttons;
-		buttons.btn_left = rl::is_mouse_button_down(rl::MOUSE_BUTTON_LEFT);
-		buttons.btn_right = rl::is_mouse_button_down(rl::MOUSE_BUTTON_RIGHT);
-		buttons.btn_middle = rl::is_mouse_button_down(rl::MOUSE_BUTTON_MIDDLE);
-		ui.input_mouse_button(buttons);
 		/* End Input Handling */
 
 		/* Start UI Handling */
 		ui.frame_begin()!!;
 
-		// main div, fill the whole window
-		ui.div_begin("main", ugui::Rect{.w=ui.width/2})!!;
-		{|
+		if (ui.check_key_combo(ugui::KMOD_CTRL, "q")) quit = true;
 
-			ui.layout_set_row()!!;
-			if (ui.button("button0", ugui::Rect{0,0,30,30})!!.mouse_press) {
-				io::printn("press button0");
-				toggle = !toggle;
-				ui.force_update()!!;
-			}
-			//ui.layout_next_column()!!;
-			if (ui.button("button1", ugui::Rect{0,0,30,30})!!.mouse_press) {
-				io::printn("press button1");
-			}
-			//ui.layout_next_column()!!;
-			if (toggle) {
-				if (ui.button("button2", ugui::Rect{0,0,30,30})!!.mouse_release) {
-					io::printn("release button2");
-				}
-			}
-			if (ui.slider_ver("slider", ugui::Rect{0,0,30,100})!!.update) {
-				ugui::Elem* e = ui.get_elem_by_label("slider")!!;
-				io::printfn("slider: %f", e.slider.value);
-			}
+const String APPLICATION = "calculator";
+$if APPLICATION == "debug":
+		debug_app(&ui);
+$endif
+$if APPLICATION == "calculator":
+		calculator(&ui);
+$endif
 
-			ui.text_unbounded("text1", "Ciao Mamma\nAbilità ⚡")!!;
-		|};
-		ui.div_end()!!;
+		// Timings counter
+		TimeStats dts = draw_times.get_stats();
+		TimeStats uts = ui_times.get_stats();
 
-		ui.div_begin("second", ugui::DIV_FILL)!!;
-		ugui::Elem* de = ui.get_elem_by_label("second")!!;
-		de.div.scroll.can_y = true;
-		{|
+		ui.layout_set_floating()!!;
+		// FIXME: I cannot anchor shit to the bottom of the screen
+		ui.div_begin({0, ui.height-150, -300, 150})!!;
+		{
 			ui.layout_set_column()!!;
-			if (ui.slider_ver("slider_other", ugui::Rect{0,0,30,100})!!.update) {
-				ugui::Elem* e = ui.get_elem_by_label("slider_other")!!;
-				io::printfn("other slider: %f", e.slider.value);
-			}
-			ui.button("button10", ugui::Rect{0,0,50,50})!!;
-			ui.button("button11", ugui::Rect{0,0,50,50})!!;
-			ui.button("button12", ugui::Rect{0,0,50,50})!!;
-			ui.button("button13", ugui::Rect{0,0,50,50})!!;
-			ui.button("button14", ugui::Rect{0,0,50,50})!!;
-			ui.button("button15", ugui::Rect{0,0,50,50})!!;
-			ui.button("button16", ugui::Rect{0,0,50,50})!!;
-			ui.button("button17", ugui::Rect{0,0,50,50})!!;
-		|};
+			ui.text_unbounded(string::tformat("frame %d, fps = %.2f", frame, fps))!!;
+			ui.text_unbounded(string::tformat("ui avg: %s\ndraw avg: %s\nTOT: %s", uts.avg, dts.avg, uts.avg+dts.avg))!!;
+			ui.text_unbounded(string::tformat("%s %s", mod.lctrl, (String)ui.input.keyboard.text[:ui.input.keyboard.text_len]))!!;
+		};
 		ui.div_end()!!;
 
 		ui.frame_end()!!;
 		/* End UI Handling */
 		ui_times.push(clock.mark());
-		ui_times.print_stats();
+		//ui_times.print_stats();
+
 
 		/* Start UI Drawing */
-		rl::begin_drawing();
-		// ClearBackground(BLACK);
+		ren.begin_render(true);
 
-		rl::Color c;
-		rl::Rectangle r;
-		static rl::Image font_atlas;
-		static rl::Texture2D font_texture;
-		for (Cmd* cmd; (cmd = ui.cmd_queue.dequeue() ?? null) != null;) {
-			switch (cmd.type) {
-			case ugui::CmdType.CMD_RECT:
-				c = rl::Color{
-				    .r = cmd.rect.color.r,
-				    .g = cmd.rect.color.g,
-				    .b = cmd.rect.color.b,
-				    .a = cmd.rect.color.a,
-				};
-				r = rl::Rectangle{
-					.x = cmd.rect.rect.x,
-					.y = cmd.rect.rect.y,
-					.height = cmd.rect.rect.h,
-					.width = cmd.rect.rect.w,
-				};
-			    float rad = cmd.rect.radius;
-				// for some weird-ass reason the straight forward inverse formula does not work
-			    float roundness = r.width > r.height ? (2.1*rad)/r.height : (2.1*rad)/r.width;
-				rl::draw_rectangle_rounded(r, roundness, 0, c);
-			case ugui::CmdType.CMD_UPDATE_ATLAS:
-				rl::unload_image(font_atlas);
-				font_atlas.data = cmd.update_atlas.raw_buffer;
-				font_atlas.width = cmd.update_atlas.width;
-				font_atlas.height = cmd.update_atlas.height;
-				font_atlas.mipmaps = 1;
-				//font_atlas.format = rl::PixelFormat.PIXELFORMAT_UNCOMPRESSED_GRAYSCALE;
-				font_atlas.format = 1;
-				if (rl::is_texture_ready(font_texture)) {
-					rl::unload_texture(font_texture);
-				}
-				font_texture = rl::load_texture_from_image(font_atlas);
-				//rl::draw_texture(font_texture, 0, 0, rl::WHITE);
-			case ugui::CmdType.CMD_SPRITE:
-				rl::Rectangle source = {
-					.x = cmd.sprite.texture_rect.x,
-					.y = cmd.sprite.texture_rect.y,
-					.width = cmd.sprite.texture_rect.w,
-					.height = cmd.sprite.texture_rect.h,
-				};
-				rl::Vector2 position = {
-					.x = cmd.sprite.rect.x,
-					.y = cmd.sprite.rect.y,
-				};
+		ren.render_ugui(&ui.cmd_queue);
+		
+		ren.end_render();
 
-				rl::draw_texture_rec(font_texture, source, position, rl::WHITE);
-				//rl::draw_rectangle(cmd.sprite.rect.x,
-				//    cmd.sprite.rect.y,
-				//    cmd.sprite.rect.w,
-				//    cmd.sprite.rect.h,
-				//    rl::WHITE
-				//);
-			default:
-				io::printfn("Unknown cmd type: %s", cmd.type);
-			}
-		}
 		draw_times.push(clock.mark());
-		draw_times.print_stats();
-		rl::end_drawing();
+		//draw_times.print_stats();
 		/* End Drawing */
 
+		// wait for the next event, timeout after 100ms
+
+		sdl::wait_event_timeout(&e, (int)(100.0-sleep_clock.mark().to_ms()-0.5));
+				
+		fps = 1.0 / fps_clock.mark().to_sec();
+		frame++;
 	}
 
-	rl::close_window();
-
-	ui.font.free();
-	ui.free();
 	return 0;
 }
 
-/*
-fn void! test_vtree() @test
+fn void debug_app(ugui::Ctx* ui)
 {
-	vtree::VTree(<String>) vt;
-	vt.init(10)!!;
-	defer vt.free();
-
-	assert(vt.size() == 10, "Size is incorrect");
-
-	isz ref = vt.add("Ciao Mamma", 0)!!;
-	String s = vt.get(ref)!!;
-	assert(s == "Ciao Mamma", "String is incorrect");
-	isz par = vt.parentof(0)!!;
-	assert(ref == par, "Not Root");
-
-	vt.print();
-}
-
-def StrCache = cache::Cache(<int, String, 256>);
-fn void! test_cache() @test
-{
-	StrCache cc;
-	cc.init()!!;
-	defer cc.free();
-
-	String*! r = cc.search(1);
-	if (catch ex = r) {
-		if (ex != SearchResult.MISSING) {
-			return ex?;
+	static bool toggle;
+	ui.div_begin({.w=-100})!!;
+	{
+		ui.layout_set_column()!!;
+		if (ui.button(icon:"tux")!!.mouse_press) {
+			io::printn("press button0");
+			toggle = !toggle;
 		}
+		//ui.layout_next_column()!!;
+		if (ui.button(label: "ciao", icon: "tick")!!.mouse_press) {
+			io::printn("press button1");
+		}
+		//ui.layout_next_column()!!;
+		if (ui.button()!!.mouse_release) {
+			io::printn("release button2");
 		}
 
-	r = cc.get_or_insert(&&"Ciao Mamma", 1)!;
-	assert(*r!! == "Ciao Mamma", "incorrect string");
+		ui.layout_set_row()!!;
+		ui.layout_next_row()!!;
+		static float rf, gf, bf, af;
+		ui.slider_ver({0,0,30,100}, &rf)!!;
+		ui.slider_ver({0,0,30,100}, &gf)!!;
+		ui.slider_ver({0,0,30,100}, &bf)!!;
+		ui.slider_ver({0,0,30,100}, &af)!!;
+
+		ui.layout_next_column()!!;
+		ui.text_unbounded("Ciao Mamma\nAbilità ⚡\n'\udb80\udd2c'")!!;
+
+		ui.layout_next_column()!!;
+		ui.button("Continua!")!!;
+
+		ui.layout_next_row()!!;
+		static bool check;
+		ui.checkbox("", {}, &check, "tick")!!;
+		ui.checkbox("", {}, &check)!!;
+		ui.toggle("", {}, &toggle)!!;
+	};
+	ui.sprite("tux")!!;
+	
+	static char[128] text_box = "ciao mamma";
+	static usz text_len = "ciao mamma".len;
+	ui.text_box({0,0,200,200}, text_box[..], &text_len)!!;
+
+	ui.div_end()!!;
+
+	ui.div_begin(ugui::DIV_FILL, scroll_x: true, scroll_y: true)!!;
+	{
+		ui.layout_set_column()!!;
+		static float slider2 = 0.5;
+		if (ui.slider_ver({0,0,30,100}, &slider2)!!.update) {
+			io::printfn("other slider: %f", slider2);
+		}
+		ui.button()!!;
+		ui.button()!!;
+		ui.button()!!;
+		ui.button()!!;
+		if (toggle) {
+			ui.button()!!;
+			ui.button()!!;
+			ui.button()!!;
+			ui.button()!!;
+		}
+		ui.layout_next_column()!!;
+		ui.layout_set_row()!!;
+		static float f1, f2;
+		ui.slider_hor({0,0,100,30}, &f1)!!;
+		ui.slider_hor({0,0,100,30}, &f2)!!;
+	};
+	ui.div_end()!!;
+}
+
+fn void calculator(ugui::Ctx* ui)
+{
+	ui.div_begin(ugui::DIV_FILL)!!;
+
+	ui.layout_set_row()!!;
+	ui.div_begin({0,0,-300,50})!!;
+	ui.text_unbounded("80085")!!;
+	ui.div_end()!!;
+	ui.layout_next_row()!!;
+	
+	ui.button("7")!!;
+	ui.button("8")!!;
+	ui.button("9")!!;
+	ui.layout_next_row()!!;
+	ui.button("4")!!;
+	ui.button("5")!!;
+	ui.button("6")!!;
+	ui.layout_next_row()!!;
+	ui.button("3")!!;
+	ui.button("2")!!;
+	ui.button("1")!!;
+	ui.layout_next_row()!!;
+	ui.button(".")!!;
+	ui.button("0")!!;
+	ui.button("")!!;
+	
+	ui.layout_next_column()!!;
+	ui.layout_set_column()!!;
+	ui.button("+")!!;
+	ui.button("-")!!;
+	ui.button("*")!!;
+	ui.button("/")!!;
+	
+	ui.div_end()!!;
 }
-*/

src/renderer.c3

@@ -0,0 +1,962 @@
+module idlist{Type};
+
+// extends the List type to search elements that have a type.id property
+// TODO: check that type has an id
+
+import std::collections::list;
+
+alias IdList = List{Type};
+
+macro Type* IdList.get_from_name(&self, String name)
+{
+	return self.get_from_id(name.hash());
+}
+
+macro Type* IdList.get_from_id(&self, id)
+{
+	foreach(&s: self) {
+		if (s.id == id) {
+			return s;
+		}
+	}
+	return null;
+}
+
+module sdlrenderer::ren;
+
+// 2D renderer for ugui, based on SDL3 using the new GPU API
+
+import std::io;
+import std::core::mem;
+import sdl3::sdl;
+import idlist;
+import ugui;
+
+struct Shader {
+	sdl::GPUShader* frag;
+	sdl::GPUShader* vert;
+	ugui::Id id;
+}
+
+struct Pipeline {
+	sdl::GPUGraphicsPipeline* pipeline;
+	ugui::Id id;
+}
+
+struct Texture {
+	sdl::GPUTexture* texture;
+	sdl::GPUSampler* sampler;
+	ushort width, height;
+	ugui::Id id;
+}
+
+// The GPU buffers that contain quad info, the size is determined by MAX_QUAD_BATCH
+const int MAX_QUAD_BATCH = 2048;
+struct QuadBuffer {
+	sdl::GPUBuffer* vert_buf; // on-gpu vertex buffer
+	sdl::GPUBuffer* idx_buf;  // on-gpu index buffer
+	sdl::GPUBuffer* attr_buf; // on-gpu quad attribute buffer
+
+	sdl::GPUTransferBuffer* attr_ts;
+
+	QuadAttributes[] attr_ts_mapped;
+
+	// how many quads are currently stored
+	int count;
+
+	bool initialized;
+}
+
+alias ShaderList   = IdList{Shader};
+alias PipelineList = IdList{Pipeline};
+alias TextureList  = IdList{Texture};
+
+struct Renderer {
+	sdl::Window* win;
+	sdl::GPUDevice* gpu;
+	sdl::GPURenderPass* render_pass;
+	sdl::GPUTexture* swapchain_texture;
+	sdl::GPUCommandBuffer* render_cmdbuf;
+
+	QuadBuffer quad_buffer;
+	ShaderList shaders;
+	PipelineList pipelines;
+	TextureList textures;
+
+	Id sprite_atlas_id;
+	Id font_atlas_id;
+
+	int scissor_x, scissor_y, scissor_w, scissor_h; 
+}
+
+// How each vertex is represented in the gpu
+struct Vertex {
+	short x, y;
+}
+
+// Attributes of each quad instance
+struct QuadAttributes {
+	struct pos {
+		short x, y, w, h;
+	}
+	struct uv {
+		short u, v;
+	}
+	uint color;
+}
+
+// A single quad
+struct Quad {
+	struct vertices {
+		Vertex v1,v2,v3,v4;
+	}
+	struct indices {
+		short i1,i2,i3,i4,i5,i6;
+	}
+}
+
+struct ViewsizeUniform @align(16) {
+	int w, h;
+}
+
+const int DEBUG = 1;
+const bool CYCLE = true;
+
+fn void Renderer.init(&self, ZString title, uint width, uint height, bool vsync)
+{
+	// set wayland hint automagically
+$if DEBUG == 0:
+	bool has_wayland = false;
+	for (int i = 0; i < sdl::get_num_video_drivers(); i++) {
+		ZString driver = sdl::get_video_driver(i);
+		if (driver.str_view() == "wayland") {
+			has_wayland = true;
+			break;
+		}
+	}
+
+	if (has_wayland) {
+		sdl::set_hint(sdl::HINT_VIDEO_DRIVER, "wayland");
+	}
+$else
+	// in debug mode set the video driver to X11 because renderdoc
+	// doesn't support debugging in wayland yet. 
+	sdl::set_hint(sdl::HINT_VIDEO_DRIVER, "x11");
+	sdl::set_hint(sdl::HINT_RENDER_GPU_DEBUG, "1");
+$endif
+
+	// init subsystems
+	if (!sdl::init(INIT_VIDEO)) {
+		unreachable("sdl error: %s", sdl::get_error());
+	}
+
+	// create the window
+	self.win = sdl::create_window(title, width, height, WINDOW_RESIZABLE|WINDOW_VULKAN);
+	if (self.win == null) {
+		unreachable("sdl error: %s", sdl::get_error());
+	}
+
+	// get the gpu device handle
+	self.gpu = sdl::create_gpu_device(GPU_SHADERFORMAT_SPIRV, true, "vulkan");
+	if (self.gpu == null) {
+		unreachable("failed to create gpu device: %s", sdl::get_error());
+	}
+
+	if (!sdl::claim_window_for_gpu_device(self.gpu, self.win)) {
+		unreachable("failed to claim window for use with gpu: %s", sdl::get_error());
+	}
+
+	// set swapchain parameters, like vsync
+	GPUPresentMode present_mode = vsync ? GPU_PRESENTMODE_VSYNC : GPU_PRESENTMODE_IMMEDIATE;
+	sdl::set_gpu_swapchain_parameters(self.gpu, self.win, GPU_SWAPCHAINCOMPOSITION_SDR, present_mode);
+
+	//
+	// initialize the quad buffer
+	// ==========================
+	QuadBuffer* qb = &self.quad_buffer;
+
+	// since instanced rendering is used, on the gpu there is only one mesh, a single quad.
+
+	// create the vertex and index buffer on the gpu
+	qb.vert_buf = sdl::create_gpu_buffer(self.gpu,
+		&&(GPUBufferCreateInfo){.usage = GPU_BUFFERUSAGE_VERTEX, .size = Quad.vertices.sizeof}
+	);
+	if (qb.vert_buf == null) {
+		unreachable("failed to initialize quad buffer (vertex): %s", sdl::get_error());
+	}
+
+	qb.idx_buf = sdl::create_gpu_buffer(self.gpu,
+		&&(GPUBufferCreateInfo){.usage = GPU_BUFFERUSAGE_INDEX, .size = Quad.indices.sizeof}
+	);
+	if (qb.idx_buf == null) {
+		unreachable("failed to initialize quad buffer (index): %s", sdl::get_error());
+	}
+
+	qb.attr_buf = sdl::create_gpu_buffer(self.gpu,
+		&&(GPUBufferCreateInfo){.usage = GPU_BUFFERUSAGE_VERTEX, .size = QuadAttributes.sizeof * MAX_QUAD_BATCH}
+	);
+	if (qb.attr_buf == null) {
+		unreachable("failed to initialize quad buffer (index): %s", sdl::get_error());
+	}
+
+
+	// upload the quad mesh
+	GPUTransferBuffer *ts =  sdl::create_gpu_transfer_buffer(self.gpu,
+		&&(GPUTransferBufferCreateInfo){.usage = GPU_TRANSFERBUFFERUSAGE_UPLOAD, .size = Quad.sizeof}
+	);
+	if (ts == null) {
+		unreachable("failed to create gpu transfer buffer: %s", sdl::get_error());
+	}
+	Quad* quad = (Quad*)sdl::map_gpu_transfer_buffer(self.gpu, ts, false);
+
+	/* v1            v4
+	 * +-------------+
+	 * |           _/|
+	 * |         _/  |
+	 * |   1   _/    |
+	 * |     _/      |
+	 * |   _/        |
+	 * | _/     2    |
+	 * |/            |
+	 * +-------------+
+	 * v2            v3
+	 */
+	quad.vertices.v1 = {.x = 0, .y = 0};
+	quad.vertices.v2 = {.x = 0, .y = 1};
+	quad.vertices.v3 = {.x = 1, .y = 1};
+	quad.vertices.v4 = {.x = 1, .y = 0};
+	// triangle 1 indices
+	quad.indices.i1 = 0; // v1
+	quad.indices.i2 = 1; // v2
+	quad.indices.i3 = 3; // v4
+	// triangle 2 indices
+	quad.indices.i4 = 1; // v2
+	quad.indices.i5 = 2; // v3
+	quad.indices.i6 = 3; // v4
+	
+	sdl::unmap_gpu_transfer_buffer(self.gpu, ts);
+
+	GPUCommandBuffer* cmd = sdl::acquire_gpu_command_buffer(self.gpu);
+	if (cmd == null) {
+		unreachable("failed to upload quad at acquiring command buffer: %s", sdl::get_error());
+	}
+	GPUCopyPass* cpy = sdl::begin_gpu_copy_pass(cmd);
+
+	// upload vertices
+	sdl::upload_to_gpu_buffer(cpy, 
+		&&(GPUTransferBufferLocation){.transfer_buffer = ts, .offset = Quad.vertices.offsetof},
+		&&(GPUBufferRegion){.buffer = qb.vert_buf, .offset = 0, .size = Quad.vertices.sizeof},
+		false
+	);
+	// upload indices
+	sdl::upload_to_gpu_buffer(cpy, 
+		&&(GPUTransferBufferLocation){.transfer_buffer = ts, .offset = Quad.indices.offsetof},
+		&&(GPUBufferRegion){.buffer = qb.idx_buf, .offset = 0, .size = Quad.indices.sizeof},
+		false
+	);
+
+	sdl::end_gpu_copy_pass(cpy);
+	if (!sdl::submit_gpu_command_buffer(cmd)) {
+		unreachable("failed to upload quads at submit command buffer: %s", sdl::get_error());
+	}
+	sdl::release_gpu_transfer_buffer(self.gpu, ts);
+
+
+	// create and map the quad attributes transfer buffer
+	qb.attr_ts = sdl::create_gpu_transfer_buffer(self.gpu,
+		&&(GPUTransferBufferCreateInfo){.usage = GPU_TRANSFERBUFFERUSAGE_UPLOAD, .size = QuadAttributes.sizeof * MAX_QUAD_BATCH}
+	);
+	if (qb.attr_ts == null) {
+		unreachable("failed to create gpu transfer buffer: %s", sdl::get_error());
+	}
+	qb.attr_ts_mapped = ((QuadAttributes*)sdl::map_gpu_transfer_buffer(self.gpu, qb.attr_ts, false))[:MAX_QUAD_BATCH];
+	if (qb.attr_ts_mapped.ptr == null) {
+		unreachable("failed to map vertex or index buffers: %s", sdl::get_error());
+	}
+
+
+	qb.initialized = true;
+}
+
+fn void Renderer.free(&self)
+{
+	foreach (&s: self.shaders) {
+		sdl::release_gpu_shader(self.gpu, s.frag);
+		sdl::release_gpu_shader(self.gpu, s.vert);
+	}
+	self.shaders.free();
+
+	foreach (&p: self.pipelines) {
+		sdl::release_gpu_graphics_pipeline(self.gpu, p.pipeline);
+	}
+	self.pipelines.free();
+
+	foreach (&t: self.textures) {
+		sdl::release_gpu_texture(self.gpu, t.texture);
+		sdl::release_gpu_sampler(self.gpu, t.sampler);
+	}
+	self.textures.free();
+
+	QuadBuffer* qb = &self.quad_buffer;
+	sdl::unmap_gpu_transfer_buffer(self.gpu, qb.attr_ts);
+	sdl::release_gpu_transfer_buffer(self.gpu, qb.attr_ts);
+	sdl::release_gpu_buffer(self.gpu, qb.vert_buf);
+	sdl::release_gpu_buffer(self.gpu, qb.idx_buf);
+	sdl::release_gpu_buffer(self.gpu, qb.attr_buf);
+
+	sdl::release_window_from_gpu_device(self.gpu, self.win);
+	sdl::destroy_gpu_device(self.gpu);
+	sdl::destroy_window(self.win);
+	sdl::quit();
+}
+
+fn void Renderer.resize_window(&self, uint width, uint height)
+{
+	sdl::set_window_size(self.win, width, height);
+}
+
+fn void Renderer.get_window_size(&self, int* width, int* height)
+{
+	sdl::get_window_size_in_pixels(self.win, width, height);
+}
+
+
+// Both the vertex shader and fragment shader have an implicit uniform buffer at binding 0 that
+// contains the viewport size. It is populated automatically at every begin_render() call
+fn void Renderer.load_spirv_shader_from_mem(&self, String name, char[] vert_code, char[] frag_code, uint textures, uint uniforms)
+{
+	Shader s;
+	s.id = name.hash();
+
+	if (vert_code.len == 0 || frag_code.len == 0) {
+		unreachable("vertex shader and fragment shader cannot be empty");
+	}
+
+	if (vert_code.len > 0) {
+		// FIXME: these should be passed by parameter and/or automatically determined by parsing
+		//        the shader code
+		GPUShaderCreateInfo shader_info = {
+			.code = vert_code.ptr,
+			.code_size = vert_code.len,
+			.entrypoint = "main",
+			.format = GPU_SHADERFORMAT_SPIRV,
+			.stage = GPU_SHADERSTAGE_VERTEX,
+			.num_samplers = 0,
+			.num_uniform_buffers = 1+uniforms,
+			.num_storage_buffers = 0,
+			.num_storage_textures = 0
+		};
+
+		s.vert = sdl::create_gpu_shader(self.gpu, &shader_info);
+		if (s.vert == null) {
+			unreachable("failed to create gpu vertex shader: %s", sdl::get_error());
+		}
+	}
+
+	if (frag_code.len > 0) {
+		// FIXME: these should be passed by parameter and/or automatically determined by parsing
+		//        the shader code
+		GPUShaderCreateInfo shader_info = {
+			.code = frag_code.ptr,
+			.code_size = frag_code.len,
+			.entrypoint = "main",
+			.format = GPU_SHADERFORMAT_SPIRV,
+			.stage = GPU_SHADERSTAGE_FRAGMENT,
+			.num_samplers = textures,
+			.num_uniform_buffers = 1,
+			.num_storage_buffers = 0,
+			.num_storage_textures = 0
+		};
+
+		s.frag = sdl::create_gpu_shader(self.gpu, &shader_info);
+		if (s.frag == null) {
+			unreachable("failed to create gpu fragment shader: %s", sdl::get_error());
+		}
+	}
+
+	// push the shader into the list
+	self.shaders.push(s);
+}
+
+fn void Renderer.load_spirv_shader_from_file(&self, String name, String vert_path, String frag_path, uint textures, uint uniforms) 
+{
+	if (vert_path == "" || frag_path == "") {
+		unreachable("need both a vertex shader and fragment shader path");
+	}
+
+	char[] vert_code;
+	char[] frag_code;
+
+	// create vertex shader
+	usz size = file::get_size(vert_path)!!;
+	vert_code = mem::new_array(char, size + size%4);
+	file::load_buffer(vert_path, vert_code)!!;
+	defer mem::free(vert_code);
+
+	// create fragment shader
+	size = file::get_size(frag_path)!!;
+	frag_code = mem::new_array(char, size + size%4);
+	file::load_buffer(frag_path, frag_code)!!;
+	defer mem::free(frag_code);
+
+	self.load_spirv_shader_from_mem(name, vert_code, frag_code, textures, uniforms);
+}
+
+// this describes what we want to draw, since for drawing different things we have to change
+// the GPUPrimitiveType and GPURasterizerState for the pipeline.
+enum PipelineType : (GPUPrimitiveType primitive_type, GPURasterizerState raster_state) {
+	RECT   = {GPU_PRIMITIVETYPE_TRIANGLELIST, {.fill_mode = GPU_FILLMODE_FILL, .cull_mode = GPU_CULLMODE_NONE, .front_face = GPU_FRONTFACE_COUNTER_CLOCKWISE}},
+	SPRITE = {GPU_PRIMITIVETYPE_TRIANGLELIST, {.fill_mode = GPU_FILLMODE_FILL, .cull_mode = GPU_CULLMODE_NONE, .front_face = GPU_FRONTFACE_COUNTER_CLOCKWISE}},
+	LINE   = {GPU_PRIMITIVETYPE_LINELIST,     {.fill_mode = GPU_FILLMODE_LINE, .cull_mode = GPU_CULLMODE_NONE, .front_face = GPU_FRONTFACE_COUNTER_CLOCKWISE}},
+}
+
+// create a graphics pipeline to draw to the window using a set of vertex/fragment shaders
+// the pipeline is pushed into the renderer's pipeline list and it will have the same id as
+// the shader set.
+fn void Renderer.create_pipeline(&self, String shader_name, PipelineType type)
+{
+	Shader *s = self.shaders.get_from_name(shader_name);
+	if (s == null) {
+		unreachable("error in creating pipeline: no shader named %s", shader_name);
+	}
+
+	GPUGraphicsPipelineCreateInfo ci = {
+		.vertex_shader = s.vert,
+		.fragment_shader = s.frag,
+		// This structure specifies how the vertex buffer looks in memory, what it contains
+		// and what is passed where to the gpu. Each vertex has three attributes, position,
+		// color and uv coordinates. Since this is a 2D pixel-based renderer the position 
+		// is represented by two floats, the color as 32 bit rgba and the uv also as intgers. 
+		.vertex_input_state = {
+			// the description of each vertex buffer, for now I use only one buffer
+			.vertex_buffer_descriptions = (GPUVertexBufferDescription[]){
+				{ // first slot, per-vertex attributes
+					.slot = 0,
+					.pitch = Vertex.sizeof,
+					.input_rate = GPU_VERTEXINPUTRATE_VERTEX,
+				},
+				{ // second slot, per-instance attributes
+					.slot = 1,
+					.pitch = QuadAttributes.sizeof,
+					.input_rate = GPU_VERTEXINPUTRATE_INSTANCE,
+				}
+			},
+			.num_vertex_buffers = 2,
+			// the description of each vertex
+			.vertex_attributes = (GPUVertexAttribute[]){
+				{ // at location zero there is the position of the vertex
+					.location = 0,
+					.buffer_slot = 0, // buffer slot zero so per-vertex
+					.format = GPU_VERTEXELEMENTFORMAT_SHORT2, // x,y
+					.offset = 0,
+				},
+				{ // at location one there is the per-quad position
+					.location = 1,
+					.buffer_slot = 1, // buffer slot one so per-instance
+					.format = GPU_VERTEXELEMENTFORMAT_SHORT4, // x,y,w,h
+					.offset = QuadAttributes.pos.offsetof,
+				},
+				{ // at location two there are the per-quad uv coordinates
+					.location = 2,
+					.buffer_slot = 1,
+					.format = GPU_VERTEXELEMENTFORMAT_SHORT2,
+					.offset = QuadAttributes.uv.offsetof,
+				},
+				{ // at location three there is the quad color
+					.location = 3,
+					.buffer_slot = 1,
+					.format = GPU_VERTEXELEMENTFORMAT_UBYTE4,
+					.offset = QuadAttributes.color.offsetof,
+				}
+			},
+			.num_vertex_attributes = 4,
+		},
+		// the pipeline's primitive type and rasterizer state differs based on what needs to
+		// be drawn
+		.primitive_type = type.primitive_type,
+		.rasterizer_state = type.raster_state,
+		.multisample_state = {},  // no multisampling, all zeroes
+		.depth_stencil_state = {},  // no stencil test, all zeroes
+		.target_info = { // the target (texture) description
+			.color_target_descriptions = (GPUColorTargetDescription[]){{
+				// rendering happens to the window, so get it's format
+				.format = sdl::get_gpu_swapchain_texture_format(self.gpu, self.win),
+				.blend_state = {
+					// alpha blending on everything
+					// https://en.wikipedia.org/wiki/Alpha_compositing
+					.src_color_blendfactor = GPU_BLENDFACTOR_SRC_ALPHA,
+					.dst_color_blendfactor = GPU_BLENDFACTOR_ONE_MINUS_SRC_ALPHA,
+					.color_blend_op = GPU_BLENDOP_ADD,
+					.src_alpha_blendfactor = GPU_BLENDFACTOR_SRC_ALPHA,
+					.dst_alpha_blendfactor = GPU_BLENDFACTOR_ONE_MINUS_SRC_ALPHA,
+					.alpha_blend_op = GPU_BLENDOP_ADD,
+					.enable_blend = true,
+					// color write mask is not enabled so all rgba channels are written to
+				},
+			}},
+			.num_color_targets = 1,
+			.depth_stencil_format = {}, // FIXME: no stencil, no depth buffering
+			.has_depth_stencil_target = false,
+		},
+	};
+
+	// create the pipeline and add it to the pipeline list
+	Pipeline p = {
+		.id = s.id,
+		.pipeline = sdl::create_gpu_graphics_pipeline(self.gpu, &ci),
+	};
+
+	if (p.pipeline == null) {
+		unreachable("failed to create pipeline (shaders: %s, type: %s): %s", shader_name, type.nameof, sdl::get_error());
+	}
+
+	self.pipelines.push(p);
+}
+
+// NOTE: with TEXTUREUSAGE_SAMPLER the texture format cannot be intger _UINT so it has to be nermalized
+enum TextureType : (GPUTextureFormat format) {
+	FULL_COLOR = GPU_TEXTUREFORMAT_R8G8B8A8_UNORM,
+	JUST_ALPHA = GPU_TEXTUREFORMAT_R8_UNORM
+} 
+
+macro void Renderer.new_texture(&self, name_or_id, TextureType type, char[] pixels, uint width, uint height)
+{
+	$switch $typeof(name_or_id):
+	$case uint: return self.new_texture_by_id(id, type, pixels, width, height);
+	$case String: return self.new_texture_by_id(name_or_id.hash(), type, pixels, width, height);
+	$default: unreachable("texture must have a name (String) or an id (uint)");
+	$endswitch
+}
+
+macro void Renderer.update_texture(&self, name_or_id, char[] pixels, uint width, uint height, uint x = 0, uint y = 0)
+{
+	$switch $typeof(name_or_id):
+	$case uint: return self.update_texture_by_id(name_or_id, pixels, width, height, x, y);
+	$case String: return self.update_texture_by_id(name_or_id.hash(), pixels, width, height, x, y);
+	$default: unreachable("texture must have a name (String) or an id (uint)");
+	$endswitch
+}
+
+
+// create a new gpu texture from a pixel buffer, the format has to be specified
+// the new texture s given an id and pushed into a texture list
+fn void Renderer.new_texture_by_id(&self, Id id, TextureType type, char[] pixels, uint width, uint height)
+{	
+	// the texture description
+	GPUTextureCreateInfo tci = {
+		.type = GPU_TEXTURETYPE_2D,
+		.format = type.format,
+		// all textures are used with samplers, which means read-only textures that contain data to be sampled
+		.usage = GPU_TEXTUREUSAGE_SAMPLER,
+		.width = width,
+		.height = height,
+		.layer_count_or_depth = 1,
+		.num_levels = 1, // no mip maps so just one level
+		// .sample_count not used since the texture is not a render target
+	};
+
+	GPUTexture* texture = sdl::create_gpu_texture(self.gpu, &tci);
+	if (texture == null) {
+		unreachable("failed to create texture (id: %s, type: %s): %s", id, type.nameof, sdl::get_error());
+	}
+
+	// the sampler description, how the texture should be sampled
+	GPUSamplerCreateInfo sci = {
+		.min_filter = GPU_FILTER_LINEAR, // linear interpolation for textures
+		.mag_filter = GPU_FILTER_LINEAR,
+		.mipmap_mode = GPU_SAMPLERMIPMAPMODE_NEAREST,
+		.address_mode_u = GPU_SAMPLERADDRESSMODE_REPEAT, // tiling textures
+		.address_mode_v = GPU_SAMPLERADDRESSMODE_REPEAT,
+		.address_mode_w = GPU_SAMPLERADDRESSMODE_REPEAT,
+		// everything else is not used and not needed
+	};
+
+	GPUSampler* sampler = sdl::create_gpu_sampler(self.gpu, &sci);
+	if (sampler == null) {
+		unreachable("failed to create sampler (texture id: %s, type: %s): %s", id, type.nameof, sdl::get_error());
+	}
+
+	Texture t = {
+		.id = id,
+		.texture = texture,
+		.sampler = sampler,
+	};
+	self.textures.push(t);
+
+	// upload the texture data
+	self.update_texture_by_id(id, pixels, width, height, 0, 0);
+}
+
+fn void Renderer.update_texture_by_id(&self, Id id, char[] pixels, uint width, uint height, uint x, uint y)
+{
+	Texture* t = self.textures.get_from_id(id);
+	if (t == null || t.texture == null) {
+		unreachable("failed updating texture: no texture with id %s", id);
+	}
+	GPUTexture* texture = t.texture;
+
+	// FIXME: do a better job at validating the copy
+	if (x > t.width || y > t.height) {
+		unreachable("failed updating texture: attempting to copy outside of the texture region");
+	}
+
+	// upload image data
+	GPUCommandBuffer* cmdbuf = sdl::acquire_gpu_command_buffer(self.gpu);
+	if (cmdbuf == null) {
+		unreachable("failed to upload texture data at acquiring command buffer: %s", sdl::get_error());
+	}
+	GPUCopyPass* copypass = sdl::begin_gpu_copy_pass(cmdbuf);
+	if (copypass == null) {
+		unreachable("failed to upload texture data at beginning copy pass: %s", sdl::get_error());
+	}
+
+	GPUTransferBuffer* buf = sdl::create_gpu_transfer_buffer(self.gpu,
+		&&(GPUTransferBufferCreateInfo){.usage = GPU_TRANSFERBUFFERUSAGE_UPLOAD, .size = pixels.len}
+	);
+	if (buf == null) {
+		unreachable("failed to upload texture data at creating the transfer buffer: %s", sdl::get_error());
+	}
+
+	char* gpu_mem = (char*)sdl::map_gpu_transfer_buffer(self.gpu, buf, CYCLE);
+	if (gpu_mem == null) {
+		unreachable("failed to upload texture data at mapping the transfer buffer: %s", sdl::get_error());
+	}
+	// copy the data to the driver's memory
+	gpu_mem[:pixels.len] = pixels[..];
+	sdl::unmap_gpu_transfer_buffer(self.gpu, buf);
+
+	// upload the data to gpu memory
+	sdl::upload_to_gpu_texture(copypass,
+		&&(GPUTextureTransferInfo){.transfer_buffer = buf, .offset = 0},
+		&&(GPUTextureRegion){.texture = texture, .x = x, .y = y, .w = width, .h = height, .d = 1},
+		false
+	);
+
+	sdl::end_gpu_copy_pass(copypass);
+	if (!sdl::submit_gpu_command_buffer(cmdbuf)) {
+		unreachable("failed to upload texture data at command buffer submission: %s", sdl::get_error());
+	}
+	sdl::release_gpu_transfer_buffer(self.gpu, buf);
+}
+
+
+fn bool Renderer.push_sprite(&self, short x, short y, short w, short h, short u, short v, uint color = 0xffffffff)
+{
+	QuadAttributes qa = {
+		.pos = {.x = x, .y = y, .w = w, .h = h},
+		.uv = {.u = u, .v = v},
+		.color = color
+	};
+
+	return self.map_quad(qa);
+}
+
+fn bool Renderer.push_quad(&self, short x, short y, short w, short h, uint color, ushort radius = 0)
+{
+	QuadAttributes qa = {
+		.pos = {.x = x, .y = y, .w = w, .h = h},
+		.uv  = {.u = radius, .v = radius},
+		.color = color
+	};
+
+	return self.map_quad(qa);
+}
+
+// this does not upload a quad, but it simply copies the quad data to the correct transfer buffers.
+// Data transfer to the GPU only happens in draw_quads() to save time
+fn bool Renderer.map_quad(&self, QuadAttributes qa)
+{
+	if (self.quad_buffer.count >= MAX_QUAD_BATCH) {
+		return false;
+	}
+	QuadBuffer* qb = &self.quad_buffer;
+
+	// upload the quad data to the gpu
+	if (qb.initialized == false) {
+		unreachable("quad buffer not initialized");
+	}
+
+	qb.attr_ts_mapped[qb.count] = qa;
+
+	qb.count++;
+
+	return true;
+}
+
+fn void Renderer.upload_quads(&self)
+{
+	QuadBuffer* qb = &self.quad_buffer;
+
+	GPUCommandBuffer* cmd = sdl::acquire_gpu_command_buffer(self.gpu);
+	if (cmd == null) {
+		unreachable("failed to upload quad at acquiring command buffer: %s", sdl::get_error());
+	}
+	GPUCopyPass* cpy = sdl::begin_gpu_copy_pass(cmd);
+
+	// upload quad attributes
+	sdl::upload_to_gpu_buffer(cpy, 
+		&&(GPUTransferBufferLocation){.transfer_buffer = qb.attr_ts, .offset = 0},
+		&&(GPUBufferRegion){.buffer = qb.attr_buf, .offset = 0, .size = QuadAttributes.sizeof * qb.count},
+		false
+	);
+
+	sdl::end_gpu_copy_pass(cpy);
+	if (!sdl::submit_gpu_command_buffer(cmd)) {
+		unreachable("failed to upload quads at submit command buffer: %s", sdl::get_error());
+	}
+}
+
+// draw all quads in the quad buffer, since uniforms are per-drawcall it makes no sense
+// to draw them one a the time
+fn void Renderer.draw_quads(&self, uint off, uint count)
+{
+	QuadBuffer* qb = &self.quad_buffer;
+
+	// too many quads to draw
+	if (off >= qb.count || count > qb.count - off) {
+		unreachable("too many quads, have %d, requested %d, offset %d", qb.count, count, off);
+	}
+
+	sdl::bind_gpu_vertex_buffers(self.render_pass, 0,
+		(GPUBufferBinding[]){
+			{.buffer = qb.vert_buf, .offset = 0},
+			{.buffer = qb.attr_buf, .offset = 0},
+		}, 2);
+	sdl::bind_gpu_index_buffer(self.render_pass, &&(GPUBufferBinding){.buffer = qb.idx_buf, .offset = 0}, GPU_INDEXELEMENTSIZE_16BIT);
+
+	sdl::draw_gpu_indexed_primitives(self.render_pass, 6, count, 0, 0, off);
+}
+
+fn void Renderer.reset_quads(&self)
+{
+	self.quad_buffer.count = 0;
+}
+
+
+fn void Renderer.begin_render(&self, bool clear_screen)
+{
+	self.render_cmdbuf = sdl::acquire_gpu_command_buffer(self.gpu);
+	sdl::wait_and_acquire_gpu_swapchain_texture(self.render_cmdbuf, self.win, &self.swapchain_texture, null, null);
+
+	// push the window size as a uniform
+	// TODO: maybe make this configurable and/or add more things
+	ViewsizeUniform v;
+	self.get_window_size(&v.w, &v.h);
+	sdl::push_gpu_vertex_uniform_data(self.render_cmdbuf, 0, &v, ViewsizeUniform.sizeof);
+	sdl::push_gpu_fragment_uniform_data(self.render_cmdbuf, 0, &v, ViewsizeUniform.sizeof);
+
+	if (clear_screen) {
+		GPURenderPass* pass = sdl::begin_gpu_render_pass(self.render_cmdbuf, 
+			&&(GPUColorTargetInfo){
+				.texture = self.swapchain_texture,
+				.mip_level = 0,
+				.layer_or_depth_plane = 0,
+				.clear_color = {.r = 1.0, .g = 0.0, .b = 1.0, .a = 1.0},
+				.load_op = GPU_LOADOP_CLEAR, // clear the screen at the start of the render pass
+				.store_op = GPU_STOREOP_STORE,
+				.resolve_texture = null,
+				.resolve_mip_level = 0,
+				.resolve_layer = 0,
+				.cycle = false,
+				.cycle_resolve_texture = false
+			},
+			1,
+			null // huh
+		);
+		if (pass == null) {
+			unreachable("render pass creation went wrong: %s", sdl::get_error());
+		}
+
+		sdl::end_gpu_render_pass(pass);
+	}
+}
+
+fn void Renderer.end_render(&self)
+{
+	sdl::submit_gpu_command_buffer(self.render_cmdbuf);
+	self.reset_quads();
+}
+
+fn void Renderer.start_render_pass(&self, String pipeline_name)
+{
+	self.render_pass = sdl::begin_gpu_render_pass(self.render_cmdbuf, 
+		&&(GPUColorTargetInfo){
+			.texture = self.swapchain_texture,
+			.mip_level = 0,
+			.layer_or_depth_plane = 0,
+			.clear_color = {.r = 0.0, .g = 0.0, .b = 0.0, .a = 1.0},
+			.load_op = GPU_LOADOP_DONT_CARE,
+			.store_op = GPU_STOREOP_STORE,
+			.resolve_texture = null,
+			.resolve_mip_level = 0,
+			.resolve_layer = 0,
+			.cycle = false,
+			.cycle_resolve_texture = false
+		},
+		1,
+		null // huh
+	);
+
+	if (self.render_pass == null) {
+		unreachable("render pass creation went wrong: %s", sdl::get_error());
+	}
+
+	sdl::GPUGraphicsPipeline* p;
+	p = self.pipelines.get_from_name(pipeline_name).pipeline;
+	if (p == null) {
+		unreachable("no pipeline");
+	}
+
+	sdl::bind_gpu_graphics_pipeline(self.render_pass, p);
+}
+
+fn void Renderer.end_render_pass(&self)
+{
+	sdl::end_gpu_render_pass(self.render_pass);	
+}
+
+fn void Renderer.bind_texture(&self, String texture_name)
+{
+	ren::Texture* tx = self.textures.get_from_name(texture_name);
+	sdl::bind_gpu_fragment_samplers(self.render_pass, 0, 
+		(GPUTextureSamplerBinding[]){{.texture = tx.texture, .sampler = tx.sampler}}, 1
+	);
+}
+
+fn void Renderer.set_scissor(&self, int x, int y, int w, int h)
+{
+	// in vulkan scissor size must be positive, clamp to zero
+	w = max(w, 0);
+	h = max(h, 0);
+	sdl::set_gpu_scissor(self.render_pass, &&(sdl::Rect){x,y,w,h});
+}
+
+fn void Renderer.reset_scissor(&self)
+{
+	int w, h;
+	sdl::get_window_size(self.win, &w, &h);
+	self.set_scissor(0, 0, w, h);
+}
+
+/// === NOTES ===
+/* 1. The uniform data is per-render pass. So you can do:
+ *      - push uniform
+ *      - draw 1
+ *      - draw 2
+ *    But not:
+ *      - push uniform
+ *      - draw
+ *      - push new uniform
+ *      - draw
+ *    And not even:
+ *      - draw
+ *      - push uniform
+ *      - draw
+ * 
+ * 2. The GPU buffers are read per-command-buffer and not per
+ *    render pass. So I cannot override an element in the buffer
+ *    before submitting the command buffer. 
+ */
+ /// === END NOTES ===
+
+
+fn void Renderer.render_ugui(&self, CmdQueue* queue)
+{
+	// upload pass
+	foreach (&c : queue) {
+		if (c.type == CMD_RECT) {
+			CmdRect r = c.rect;
+			self.push_quad(r.rect.x, r.rect.y, r.rect.w, r.rect.h, r.color.to_uint(), r.radius);
+		} else if (c.type == CMD_SPRITE) {
+			CmdSprite s = c.sprite;
+			self.push_sprite(s.rect.x, s.rect.y, s.texture_rect.w, s.texture_rect.h, s.texture_rect.x, s.texture_rect.y, s.hue.to_uint());
+		}
+	}
+	self.upload_quads();
+
+	Cmd* last_command;
+	uint off;
+	uint count;
+	for (Cmd* cmd; (cmd = queue.dequeue() ?? null) != null;) {
+		if (last_command == null || last_command.type != cmd.type) {
+			self.end_command(last_command, off, count);
+			self.begin_command(cmd);
+			off += count;
+			count = 0;
+		}
+
+		switch (cmd.type) {
+		case CMD_RECT: nextcase;
+		case CMD_SPRITE:
+			count++;
+		case CMD_UPDATE_ATLAS:
+			// TODO: verify the correct type
+			CmdUpdateAtlas u = cmd.update_atlas;
+			char[] pixels = u.raw_buffer[..u.width*u.height*u.bpp];
+			self.update_texture(u.id, pixels, u.width, u.height);
+		case CMD_SCISSOR:
+			ugui::Rect s = cmd.scissor.rect;
+			if (s.x == 0 && s.y == 0 && s.w == 0 && s.h == 0) {
+				self.get_window_size((int*)&s.w, (int*)&s.h);
+			}
+			self.scissor_x = s.x;
+			self.scissor_y = s.y;
+			self.scissor_w = s.w;
+			self.scissor_h = s.h;
+		default: unreachable("unknown command: %s", cmd.type);
+		}
+
+		last_command = cmd;
+	}
+	self.end_command(last_command, off, count);
+}
+
+fn void Renderer.begin_command(&self, Cmd* cmd)
+{
+	if (cmd == null) return;
+
+	switch (cmd.type) {
+	case CMD_RECT:
+		self.start_render_pass("UGUI_PIPELINE_RECT");
+		self.set_scissor(self.scissor_x, self.scissor_y, self.scissor_w, self.scissor_h);
+	case CMD_SPRITE:
+		// TODO: support multiple sprite and font atlases
+		CmdSprite s = cmd.sprite;
+		String pipeline;
+		String texture;
+		if (s.texture_id == self.sprite_atlas_id) {
+			switch (s.type) {
+			case SPRITE_NORMAL: pipeline = "UGUI_PIPELINE_SPRITE";
+			case SPRITE_SDF: pipeline = "UGUI_PIPELINE_SPRITE_SDF";
+			case SPRITE_MSDF: pipeline = "UGUI_PIPELINE_SPRITE_MSDF";
+			case SPRITE_ANIMATED: unreachable("animated sprtes are unsupported for now");
+			default: unreachable("unknown sprite type %s", s.type);
+			}
+			texture = "icons";
+		} else if (s.texture_id == self.font_atlas_id) {
+			pipeline = "UGUI_PIPELINE_FONT";
+			texture = "font1";
+		}
+		self.start_render_pass(pipeline);
+		self.bind_texture(texture);
+		self.set_scissor(self.scissor_x, self.scissor_y, self.scissor_w, self.scissor_h);
+	case CMD_UPDATE_ATLAS: break;
+	case CMD_SCISSOR: break;
+	default: unreachable("unknown command: %s", cmd.type);
+	}
+}
+
+fn void Renderer.end_command(&self, Cmd* cmd, uint off, uint count)
+{
+	if (cmd == null) return;
+
+	switch (cmd.type) {
+		case CMD_RECT: nextcase;
+		case CMD_SPRITE:
+			self.draw_quads(off, count);
+			self.end_render_pass();
+		case CMD_UPDATE_ATLAS: break;
+		case CMD_SCISSOR: break;
+		default: unreachable("unknown command: %s", cmd.type);
+	}
+}

src/ugui_button.c3

@@ -1,40 +0,0 @@
-module ugui;
-
-import std::io;
-
-// draw a button, return the events on that button
-fn ElemEvents! Ctx.button(&ctx, String label, Rect size)
-{
-	Id id = label.hash();
-
-	Elem *parent = ctx.get_parent()!;
-	Elem *c_elem = ctx.get_elem(id)!;
-	// add it to the tree
-	ctx.tree.add(id, ctx.active_div)!;
-
-	// 1. Fill the element fields
-	// this resets the flags
-	c_elem.type     = ETYPE_BUTTON;
-	Color bg_color = uint_to_rgba(0x0000ffff);
-
-	// if the element is new or the parent was updated then redo layout
-	if (c_elem.flags.is_new || parent.flags.updated) {
-		// 2. Layout
-		c_elem.bounds = ctx.position_element(parent, size, true);
-
-		// TODO: 3. Fill the button specific fields
-	}
-
-	c_elem.events = ctx.get_elem_events(c_elem);
-	if (parent.flags.has_focus) {
-		if (c_elem.events.mouse_hover) {
-			c_elem.flags.has_focus = true;
-			bg_color = uint_to_rgba(0x00ff00ff);
-		}
-	}
-
-	// Draw the button
-	ctx.push_rect(c_elem.bounds, bg_color, do_border: true, do_radius: true)!;
-
-	return c_elem.events;
-}

src/ugui_cmd.c3

@@ -1,99 +0,0 @@
-module ugui;
-
-import std::ascii;
-
-// FIXME: is this really the best solution?
-// "rect" is the bounding box of the element, which includes the border and the padding (so not just the content)
-fn void! Ctx.push_rect(&ctx, Rect rect, Color color, bool do_border = false, bool do_padding = false, bool do_radius = false)
-{
-	// FIXME: this should be culled higher up, maybe
-	if (rect.w <= 0 || rect.h <= 0) {
-		return;
-	}
-
-	Rect border = ctx.style.border;
-	Rect padding = ctx.style.padding;
-	ushort radius = ctx.style.radius;
-	Color border_color = ctx.style.brcolor;
-
-	if (do_border) {
-		Cmd cmd = {
-			.type = CMD_RECT,
-			.rect.rect = rect,
-			.rect.color = border_color,
-			.rect.radius = do_radius ? radius : 0,
-		};
-		ctx.cmd_queue.enqueue(&cmd)!;
-	}
-
-	Cmd cmd = {
-		.type = CMD_RECT,
-		.rect.rect = {
-			.x = rect.x + (do_border ? border.x : 0) + (do_padding ? padding.x : 0),
-			.y = rect.y + (do_border ? border.y : 0) + (do_padding ? padding.y : 0),
-			.w = rect.w - (do_border ? border.x+border.w : 0) - (do_padding ? padding.x+padding.w : 0),
-			.h = rect.h - (do_border ? border.y+border.h : 0) - (do_padding ? padding.y+padding.h : 0),
-		},
-		.rect.color = color,
-		.rect.radius = do_radius ? radius : 0,
-	};
-	ctx.cmd_queue.enqueue(&cmd)!;
-}
-
-// TODO: add texture id
-fn void! Ctx.push_sprite(&ctx, Rect bounds, Rect texture)
-{
-	Cmd cmd = {
-		.type = CMD_SPRITE,
-		.sprite.rect = bounds,
-		.sprite.texture_rect = texture,
-	};
-	ctx.cmd_queue.enqueue(&cmd)!;
-}
-
-fn void! Ctx.push_string(&ctx, Rect bounds, String text)
-{
-	if (text.len == 0) {
-		return;
-	}
-
-	short baseline = (short)ctx.font.ascender;
-	short line_height = (short)ctx.font.ascender - (short)ctx.font.descender;
-	short line_gap = (short)ctx.font.linegap;
-	Point orig = {
-		.x = bounds.x,
-		.y = bounds.y,
-	};
-
-	short line_len;
-	Codepoint cp;
-	usz off, x;
-	while ((cp = str_to_codepoint(text[off..], &x)) != 0) {
-		off += x;
-		Glyph* gp;
-		if (!ascii::is_cntrl((char)cp)) {
-			gp = ctx.font.get_glyph(cp)!;
-			Rect gb = {
-			.x = orig.x + line_len + gp.ox,
-			.y = orig.y + gp.oy + baseline,
-			.w = gp.w,
-			.h = gp.h,
-			};
-			Rect gt = {
-			.x = gp.u,
-			.y = gp.v,
-			.w = gp.w,
-			.h = gp.h,
-			};
-			if (rect_collision(gb, bounds)) {
-				ctx.push_sprite(gb, gt)!;
-			}
-			line_len += gp.adv;
-		} else if (cp == '\n'){
-			orig.y += line_height + line_gap;
-			line_len = 0;
-		} else {
-			continue;
-		}
-	}
-}

src/ugui_data.c3

@@ -1,240 +0,0 @@
-module ugui;
-
-import std::core::string;
-
-import vtree;
-import cache;
-import fifo;
-
-
-struct Rect {
-	short x, y, w, h;
-}
-
-struct Point {
-	short x, y;
-}
-
-struct Color{
-	char r, g, b, a;
-}
-
-// element ids are just long ints
-def Id = usz;
-
-enum ElemType {
-	ETYPE_NONE,
-	ETYPE_DIV,
-	ETYPE_BUTTON,
-	ETYPE_SLIDER,
-	ETYPE_TEXT,
-}
-
-bitstruct ElemFlags : uint {
-	bool updated : 0;
-	bool has_focus : 1;
-	bool is_new : 2;
-}
-
-bitstruct ElemEvents : uint {
-	bool key_press     : 0;
-	bool key_release   : 1;
-	bool key_hold      : 2;
-	bool mouse_hover   : 3;
-	bool mouse_press   : 4;
-	bool mouse_release : 5;
-	bool mouse_hold    : 6;
-	bool update        : 7;
-}
-
-enum DivLayout {
-	LAYOUT_ROW,
-	LAYOUT_COLUMN,
-	LAYOUT_FLOATING,
-}
-
-// div element
-struct Div {
-	DivLayout layout;
-	struct scroll {
-		bool can_x;
-		bool can_y;
-		bool on_x;
-		bool on_y;
-		float value_x;
-		float value_y;
-	}
-	Rect children_bounds;
-	Point origin_r, origin_c;
-	Color color_bg;
-}
-
-// slider element
-struct Slider {
-	float value;
-	Rect handle;
-}
-
-struct Text {
-	char* str;
-}
-
-// element structure
-struct Elem {
-	Id id;
-	ElemFlags flags;
-	ElemEvents events;
-	Rect bounds;
-	ElemType type;
-	union {
-		Div div;
-		Slider slider;
-		Text text;
-	}
-}
-
-
-// relationships between elements are stored in a tree, it stores just the ids
-def IdTree = vtree::VTree(<Id>) @private;
-
-// elements themselves are kept in a cache
-const uint MAX_ELEMENTS = 1024;
-def ElemCache = cache::Cache(<Id, Elem, MAX_ELEMENTS>) @private;
-
-def CmdQueue = fifo::Fifo(<Cmd>);
-
-fault UgError {
-	INVALID_SIZE,
-	EVENT_UNSUPPORTED,
-	UNEXPECTED_ELEMENT,
-}
-
-macro uint_to_rgba(uint u) {
-	return Color{
-		.r = (char)((u >> 24) & 0xff),
-		.g = (char)((u >> 16) & 0xff),
-		.b = (char)((u >> 8) & 0xff),
-		.a = (char)((u >> 0) & 0xff)
-	};
-}
-
-const Rect DIV_FILL = { .x = 0, .y = 0, .w = 0, .h = 0 };
-
-macro abs(a) { return a < 0 ? -a : a; }
-macro clamp(x, min, max) { return x < min ? min : (x > max ? max : x); }
-
-const uint STACK_STEP = 10;
-const uint MAX_ELEMS  = 128;
-const uint MAX_CMDS   = 256;
-const uint ROOT_ID    = 1;
-
-// command type
-enum CmdType {
-	CMD_RECT,
-	CMD_UPDATE_ATLAS,
-	CMD_SPRITE,
-}
-
-// command to draw a rect
-// TODO: implement radius
-struct CmdRect {
-	Rect rect;
-	ushort radius;
-	Color color;
-}
-
-// FIXME: For now only support black and white atlas, so PIXELFORMAT_UNCOMPRESSED_GRAYSCALE
-struct CmdUpdateAtlas {
-	char* raw_buffer;
-	short width, height;
-}
-
-// TODO:
-//    1. Add atlases as a data type
-//    2. Each atlas has an id
-struct CmdSprite {
-	Rect rect;
-	Rect texture_rect;
-}
-
-// command structure
-struct Cmd {
-	CmdType type;
-	union {
-		CmdRect rect;
-		CmdUpdateAtlas update_atlas;
-		CmdSprite sprite;
-	}
-}
-
-enum Layout {
-	ROW,
-	COLUMN,
-	FLOATING
-}
-
-// global style, similar to the css box model
-struct Style { // css box model
-	Rect  padding;
-	Rect  border;
-	Rect  margin;
-	Color bgcolor; // background color
-	Color fgcolor; // foreground color
-	Color brcolor; // border color
-	ushort radius;
-}
-
-
-struct Ctx {
-	Layout layout;
-	IdTree tree;
-	ElemCache cache;
-	CmdQueue cmd_queue;
-	// total size in pixels of the context
-	ushort width, height;
-	Style style;
-	Font font;
-
-	bool has_focus;
-	struct input {
-		InputEvents events;
-		struct mouse {
-			Point pos, delta;
-			// mouse_down:      bitmap of mouse buttons that are held
-			// mouse_updated:   bitmap of mouse buttons that have been updated
-			// mouse_released = mouse_updated & ~mouse_down
-			// mouse_pressed  = mouse_updated & mouse_down
-			MouseButtons down;
-			MouseButtons updated;
-		}
-	}
-
-	isz active_div; // tree node indicating the current active div
-}
-
-macro point_in_rect(Point p, Rect r)
-{
-	return (p.x >= r.x && p.x <= r.x + r.w) && (p.y >= r.y && p.y <= r.y + r.h);
-}
-
-// return true if rect a contains b
-macro rect_contains(Rect a, Rect b)
-{
-	return (a.x <= b.x && a.y <= b.y && a.x+a.w >= b.x+b.w && a.y+a.h >= b.y+b.h);
-}
-
-macro rect_intersection(Rect a, Rect b)
-{
-	return Rect{
-		.x = (short)max(a.x, b.x),
-		.y = (short)max(a.y, b.y),
-		.w = (short)min(a.x+a.w, b.x+b.w) - (short)max(a.x, b.x),
-		.h = (short)min(a.y+a.h, b.y+b.h) - (short)max(a.y, b.y),
-	};
-}
-
-// rect intersection not null
-macro rect_collision(Rect a, Rect b)
-{
-	return !(a.x > b.x+b.w || a.x+a.w < b.x || a.y > b.y+b.h || a.y+a.h < b.y);
-}

src/ugui_div.c3

@@ -1,115 +0,0 @@
-module ugui;
-
-import std::io;
-
-fn void! Ctx.div_begin(&ctx, String label, Rect size)
-{
-	Id id = label.hash();
-
-	Elem *parent = ctx.get_parent()!;
-	Elem* c_elem = ctx.get_elem(id)!;
-	isz div_node = ctx.tree.add(id, ctx.active_div)!;
-	ctx.active_div = div_node;
-
-	// 1. Fill the element fields
-	c_elem.type = ETYPE_DIV;
-
-	// do layout and update flags only if the element was updated
-	if (c_elem.flags.is_new || parent.flags.updated) {
-		// 2. layout the element
-		c_elem.bounds = ctx.position_element(parent, size);
-		if (c_elem.flags.is_new) {
-			c_elem.div.children_bounds = c_elem.bounds;
-			c_elem.div.color_bg = ctx.style.bgcolor;
-			c_elem.div.scroll.can_x = false;
-			c_elem.div.scroll.can_y = false;
-			c_elem.div.scroll.value_x = 0;
-			c_elem.div.scroll.value_y = 0;
-		}
-
-		// 3. Mark the element as updated
-		c_elem.flags.updated = true;
-		// 4. Fill the div fields
-		c_elem.div.origin_c = Point{
-			.x = c_elem.bounds.x,
-			.y = c_elem.bounds.y,
-		};
-		c_elem.div.origin_r = c_elem.div.origin_c;
-		c_elem.div.layout   = parent.div.layout;
-	}
-
-	// Add the background to the draw stack
-	ctx.push_rect(c_elem.bounds, c_elem.div.color_bg)!;
-
-	// TODO: check active
-	// TODO: check resizeable
-
-	// check and draw scroll bars
-	if (!rect_contains(c_elem.bounds, c_elem.div.children_bounds)) {
-		Point cbc = {
-			.x = c_elem.div.children_bounds.x + c_elem.div.children_bounds.w,
-			.y = c_elem.div.children_bounds.y + c_elem.div.children_bounds.h,
-		};
-		Point bc = {
-			.x = c_elem.bounds.x + c_elem.bounds.w,
-			.y = c_elem.bounds.y + c_elem.bounds.h,
-		};
-		// vertical overflow, check and draw scroll bar
-		if (cbc.y > bc.y && c_elem.div.scroll.can_y) {
-			// set the scrollbar flag, is used in layout
-			c_elem.div.scroll.on_y = true;
-
-			Rect vslider = {
-				.x = c_elem.bounds.x + c_elem.bounds.w - 10,
-				.y = c_elem.bounds.y,
-				.w = 10,
-				.h = c_elem.bounds.h,
-			};
-
-			float vh = max((float)bc.y / cbc.y, (float)0.15);
-			Rect vhandle = {
-				.x = c_elem.bounds.x + c_elem.bounds.w - 10,
-				.y = (short)(c_elem.bounds.y + (int)(c_elem.bounds.h*(1-vh) * c_elem.div.scroll.value_y)),
-				.w = 10,
-				.h = (short)(c_elem.bounds.h * vh),
-			};
-
-			c_elem.events = ctx.get_elem_events(c_elem);
-			if (parent.flags.has_focus && c_elem.events.mouse_hover && c_elem.events.mouse_hold && point_in_rect(ctx.input.mouse.pos, vhandle)) {
-				short y = (short)clamp(ctx.input.mouse.pos.y - vhandle.h/2, vslider.y, vslider.y + vslider.h - vhandle.h);
-				vhandle.y = y;
-				float v = (float)(vhandle.y-vslider.y) / (float)(vslider.h-vhandle.h);
-				c_elem.div.scroll.value_y = v;
-				c_elem.flags.updated = true;
-				c_elem.div.origin_c = Point{
-					.x = c_elem.bounds.x,
-					.y = c_elem.bounds.y,
-				};
-				c_elem.div.origin_r = c_elem.div.origin_c;
-			}
-
-			ctx.push_rect(vslider, uint_to_rgba(0x999999ff))!;
-			ctx.push_rect(vhandle, uint_to_rgba(0x9999ffff))!;
-		} else {
-			c_elem.div.scroll.on_y = false;
-		}
-	}
-
-	// if the bounds are outside of the view then allocate space for scrollbars
-	DivLayout old_layout = c_elem.div.layout;
-	c_elem.div.layout = LAYOUT_FLOATING;
-	c_elem.div.layout = old_layout;
-
-	if (parent.flags.has_focus) {
-		if (point_in_rect(ctx.input.mouse.pos, c_elem.bounds)) {
-			c_elem.flags.has_focus = true;
-		}
-	}
-
-}
-
-fn void! Ctx.div_end(&ctx)
-{
-	// the active_div returns to the parent of the current one
-	ctx.active_div = ctx.tree.parentof(ctx.active_div)!;
-}

src/ugui_font.c3

@@ -1,221 +0,0 @@
-module ugui;
-
-import schrift;
-import std::collections::map;
-import std::core::mem;
-import std::io;
-
-// unicode code point, different type for a different hash
-def Codepoint = uint;
-
-
-/* width and height of a glyph contain the kering advance
- * (u,v)
- *   +-------------*---+ -
- *   |       ^     |   | ^
- *   |       |oy   |   | |
- *   |       v     |   | |
- *   |      .ii.   |   | |
- *   |     @@@@@@. |   | |
- *   |    V@Mio@@o |   | |
- *   |    :i.  V@V |   | h
- *   |      :oM@@M |   | |
- *   |    :@@@MM@M |   | |
- *   |    @@o  o@M |   | |
- *   |<->:@@.  M@M |   | |
- *   |ox  @@@o@@@@ |   | |
- *   |    :M@@V:@@.|   | v
- *   +-------------*---+ -
- *   |<---- w ---->|
- *   |<------ adv ---->|
- */
-struct Glyph {
-	Codepoint code;
-	ushort u, v;
-	ushort w, h;
-	short adv, ox, oy;
-	short idx; // atlas index
-}
-
-const uint FONT_CACHED = 512;
-def GlyphTable = map::HashMap(<Codepoint, Glyph>) @private;
-
-fault UgFontError {
-	TTF_LOAD_FAILED,
-	MISSING_GLYPH,
-	BAD_GLYPH_METRICS,
-	RENDER_ERROR,
-}
-
-fault UgAtlasError {
-	CANNOT_PLACE,
-}
-
-// black and white atlas
-struct AtlasBW {
-	ushort width, height;
-	char[] buffer;
-
-	Point row;
-	ushort row_h;
-}
-
-struct Font {
-	schrift::Sft sft;
-	String path;
-	GlyphTable table;
-
-	float size;
-	float ascender, descender, linegap; // Line Metrics
-	AtlasBW[] atlas;
-}
-
-fn void! AtlasBW.new(&atlas, ushort width, ushort height)
-{
-	atlas.width = width;
-	atlas.height = height;
-	atlas.buffer = mem::new_array(char, (usz)atlas.width*atlas.height);
-}
-
-fn void AtlasBW.free(&atlas)
-{
-	free(atlas.buffer);
-}
-
-// place a rect inside the atlas
-// uses a row first algorithm
-// TODO: use a skyline algorithm https://jvernay.fr/en/blog/skyline-2d-packer/implementation/
-fn Point! AtlasBW.place(&atlas, char[] pixels, ushort w, ushort h)
-{
-	Point p;
-
-	if (atlas.row.x + w <= atlas.width && atlas.row.y + h <= atlas.height) {
-		p = atlas.row;
-	} else {
-		atlas.row.x = 0;
-		atlas.row.y = atlas.row.y + atlas.row_h;
-		atlas.row_h = 0;
-		if (atlas.row.x + w <= atlas.width && atlas.row.y + h <= atlas.height) {
-			p = atlas.row;
-		} else {
-			return UgAtlasError.CANNOT_PLACE?;
-		}
-	}
-
-	for (usz y = 0; y < h; y++) {
-		for (usz x = 0; x < w; x++) {
-			atlas.buffer[(usz)(p.y+y)*atlas.width + (p.x+x)] = pixels[y*w + x];
-		}
-	}
-
-	atlas.row.x += w;
-	if (h > atlas.row_h) {
-		atlas.row_h = h;
-	}
-
-	return p;
-}
-
-fn void! Font.load(&font, String path, uint height, float scale = 1)
-{
-	font.table.new_init(capacity: FONT_CACHED);
-	
-	font.size = height*scale;
-
-	font.sft = schrift::Sft{
-		.xScale = (double)font.size,
-		.yScale = (double)font.size,
-		.flags = schrift::SFT_DOWNWARD_Y,
-	};
-
-	font.sft.font = schrift::loadfile(path);
-	if (font.sft.font == null) {
-		return UgFontError.TTF_LOAD_FAILED?;
-	}
-
-	schrift::SftLMetrics lmetrics;
-	schrift::lmetrics(&font.sft, &lmetrics);
-	font.ascender  = (float)lmetrics.ascender;
-	font.descender = (float)lmetrics.descender;
-	font.linegap   = (float)lmetrics.lineGap;
-	//io::printfn("ascender:%d, descender:%d, linegap:%d", font.ascender, font.descender, font.linegap);
-
-	// TODO: allocate buffer based on FONT_CACHED and the size of a sample letter
-	//       like the letter 'A'
-	font.atlas = mem::new_array(AtlasBW, 1);
-	ushort size = (ushort)font.size*256;
-	font.atlas[0].new(size, size)!;
-	
-	// preallocate the ASCII range
-//	for (char c = ' '; c < '~'; c++) {
-//		font.get_glyph((Codepoint)c)!;
-//	}
-}
-
-fn Glyph*! Font.get_glyph(&font, Codepoint code, bool* is_new = null)
-{
-	Glyph*! gp;
-	gp = font.table.get_ref(code);
-	
-	if (catch excuse = gp) {
-		if (excuse != SearchResult.MISSING) {
-			return excuse?;
-		}
-	} else {
-		if (is_new) { *is_new = false; }
-		return gp;
-	}
-
-	// missing glyph, render and place into an atlas
-	Glyph glyph;
-
-	schrift::SftGlyph gid;
-	schrift::SftGMetrics gmtx;
-	
-	if (schrift::lookup(&font.sft, code, &gid) < 0) {
-		return UgFontError.MISSING_GLYPH?;
-	}
-
-	if (schrift::gmetrics(&font.sft, gid, &gmtx) < 0) {
-		return UgFontError.BAD_GLYPH_METRICS?;
-	}
-
-	schrift::SftImage img = {
-		.width = gmtx.minWidth,
-		.height = gmtx.minHeight,
-	};
-	char[] pixels = mem::new_array(char, (usz)img.width * img.height);
-	img.pixels = pixels;
-	if (schrift::render(&font.sft, gid, img) < 0) {
-		return UgFontError.RENDER_ERROR?;
-	}
-
-	glyph.code = code;
-	glyph.w = (ushort)img.width;
-	glyph.h = (ushort)img.height;
-	glyph.ox = (short)gmtx.leftSideBearing;
-	glyph.oy = (short)gmtx.yOffset;
-	glyph.adv = (short)gmtx.advanceWidth;
-	//io::printfn("code=%c, w=%d, h=%d, ox=%d, oy=%d, adv=%d",
-	//    glyph.code, glyph.w, glyph.h, glyph.ox, glyph.oy, glyph.adv);
-
-	Point uv = font.atlas[0].place(pixels, glyph.w, glyph.h)!;
-	glyph.idx = 0;
-	glyph.u = uv.x;
-	glyph.v = uv.y;
-
-	mem::free(pixels);
-
-	font.table.set(code, glyph);
-
-	if (is_new) { *is_new = true; }
-	return font.table.get_ref(code);
-}
-
-fn void Font.free(&font)
-{
-	foreach (atlas: font.atlas) {
-		atlas.free();
-	}
-	schrift::freefont(font.sft.font);
-}

src/ugui_impl.c3

@@ -1,152 +0,0 @@
-module ugui;
-
-import std::io;
-
-// return a pointer to the parent of the current active div
-fn Elem*! Ctx.get_parent(&ctx)
-{
-	// FIXME: if the tree held pointers to the elements then no more
-	//        redundant cache search
-	Id parent_id = ctx.tree.get(ctx.active_div)!;
-	return ctx.cache.search(parent_id);
-}
-
-// get or push an element from the cache, return a pointer to it
-// resets all flags except is_new which is set accordingly
-macro Ctx.get_elem(&ctx, Id id)
-{
-	Elem empty_elem;
-	bool is_new;
-	Elem* c_elem;
-	c_elem = ctx.cache.get_or_insert(&empty_elem, id, &is_new)!;
-	c_elem.flags = (ElemFlags)0;
-	c_elem.flags.is_new = is_new;
-	return c_elem;
-}
-
-// this searches an element in the cache by label, it does not create a new element
-// if it does't find one
-macro Ctx.get_elem_by_label(&ctx, String label)
-{
-	Id id = label.hash();
-	return ctx.cache.search(id);
-}
-
-macro Ctx.get_elem_by_tree_idx(&ctx, isz idx) @private
-{
-	Id id = ctx.tree.get(ctx.active_div)!;
-	return ctx.cache.search(id);
-}
-
-fn void! Ctx.init(&ctx)
-{
-	ctx.tree.init(MAX_ELEMENTS)!;
-	defer catch { (void)ctx.tree.free(); }
-
-	ctx.cache.init()!;
-	defer catch { (void)ctx.cache.free(); }
-
-	ctx.cmd_queue.init(MAX_ELEMENTS)!;
-	defer catch { (void)ctx.cmd_queue.free(); }
-
-	ctx.layout = Layout.ROW;
-	ctx.active_div = 0;
-
-	// TODO: add style config
-	ctx.style.margin  = Rect{2, 2, 2, 2};
-	ctx.style.border  = Rect{2, 2, 2, 2};
-	ctx.style.padding = Rect{1, 1, 1, 1};
-	ctx.style.radius  = 5;
-	ctx.style.bgcolor = uint_to_rgba(0x282828ff);
-	ctx.style.fgcolor = uint_to_rgba(0xfbf1c7ff);
-	ctx.style.brcolor = uint_to_rgba(0xd79921ff);
-}
-
-fn void Ctx.free(&ctx)
-{
-	(void)ctx.tree.free();
-	(void)ctx.cache.free();
-	(void)ctx.cmd_queue.free();
-}
-
-fn void! Ctx.frame_begin(&ctx)
-{
-
-	// 2. Get the root element from the cache and update it
-	Elem* c_elem = ctx.get_elem(ROOT_ID)!;
-	// The root should have the updated flag only if the size of the window
-	// was changed between frames, this propagates an element size recalculation
-	// down the element tree
-	c_elem.flags.updated = ctx.input.events.resize | ctx.input.events.force_update;
-	ctx.input.events.force_update = false;
-	// if the window has focus then the root element also has focus, no other
-	// computation needed, child elements need to check the mouse positon and
-	// other stuff
-	c_elem.flags.has_focus = ctx.has_focus;
-
-	if (c_elem.flags.is_new || c_elem.flags.updated) {
-		Elem def_root = {
-			.id = ROOT_ID,
-			.type = ETYPE_DIV,
-			.bounds = {
-				.w = ctx.width,
-				.h = ctx.height,
-			},
-			.div = {
-				.layout = LAYOUT_ROW,
-				.children_bounds = {
-					.w = ctx.width,
-					.h = ctx.height,
-				}
-			},
-			.flags = c_elem.flags,
-		};
-
-		*c_elem = def_root;
-	}
-
-	// 3. Push the root element into the element tree
-	ctx.active_div = ctx.tree.add(ROOT_ID, 0)!;
-
-	// The root element does not push anything to the stack
-	// TODO: add a background color taken from a theme or config
-}
-
-fn void! Ctx.force_update(&ctx)
-{
-	ctx.input.events.force_update = true;
-}
-
-fn void! Ctx.frame_end(&ctx)
-{
-	// 1. clear the tree
-	ctx.tree.prune(0)!;
-
-	// 2. clear input fields
-	bool f = ctx.input.events.force_update;
-	ctx.input.events = (InputEvents)0;
-	ctx.input.events.force_update = f;
-
-	// draw mouse position
-$if 1:
-	Cmd cmd = {
-		.type = CMD_RECT,
-		.rect.rect = {
-			.x = ctx.input.mouse.pos.x - 2,
-			.y = ctx.input.mouse.pos.y - 2,
-			.w = 4,
-			.h = 4,
-		},
-		.rect.color = uint_to_rgba(0xff00ffff)
-	};
-	ctx.cmd_queue.enqueue(&cmd)!;
-$endif
-}
-
-<*
- * @ensure elem != null
- *>
-fn bool Ctx.is_hovered(&ctx, Elem *elem)
-{
-	return point_in_rect(ctx.input.mouse.pos, elem.bounds);
-}

src/ugui_input.c3

@@ -1,114 +0,0 @@
-module ugui;
-
-import std::io;
-
-// TODO: this could be a bitstruct
-bitstruct InputEvents : uint {
-	bool resize : 0; // window size was changed
-	bool change_focus : 1; // window focus changed
-	bool mouse_move : 2; // mouse was moved
-	bool mouse_btn : 3; // mouse button pressed or released
-	bool force_update : 4;
-}
-
-// Window size was changed
-fn void! Ctx.input_window_size(&ctx, short width, short height)
-{
-	if (width <= 0 || height <= 0) {
-		return UgError.INVALID_SIZE?;
-	}
-	ctx.width = width;
-	ctx.height = height;
-	ctx.input.events.resize = true;
-}
-
-// Window gained/lost focus
-fn void Ctx.input_changefocus(&ctx, bool has_focus)
-{
-	// FIXME: raylib only has an API to query the focus status so we have to
-	//        update the input flag only if the focus changed
-	if (ctx.has_focus != has_focus) {
-		ctx.input.events.change_focus = true;
-	}
-	ctx.has_focus = has_focus;
-}
-
-bitstruct MouseButtons : uint {
-	bool btn_left : 0;
-	bool btn_middle : 1;
-	bool btn_right : 2;
-	bool btn_4 : 3;
-	bool btn_5 : 4;
-}
-
-macro Ctx.mouse_pressed(&ctx) => ctx.input.mouse.updated & ctx.input.mouse.down;
-macro Ctx.mouse_released(&ctx) => ctx.input.mouse.updated & ~ctx.input.mouse.down;
-macro Ctx.mouse_down(&ctx) => ctx.input.mouse.down;
-
-const MouseButtons BTN_NONE = (MouseButtons)0u;
-const MouseButtons BTN_ANY = (MouseButtons)(uint.max);
-const MouseButtons BTN_LEFT = {.btn_left = true};
-const MouseButtons BTN_MIDDLE = {.btn_middle = true};
-const MouseButtons BTN_RIGHT = {.btn_right = true};
-const MouseButtons BTN_4 = {.btn_4 = true};
-const MouseButtons BTN_5 = {.btn_5 = true};
-
-// FIXME: hthis compairson could be done with a cast using MouseButtons.inner
-// property but I could not figure out how
-macro Ctx.is_mouse_pressed(&ctx, MouseButtons btn) => (ctx.mouse_pressed() & btn) != BTN_NONE;
-macro Ctx.is_mouse_released(&ctx, MouseButtons btn) => (ctx.mouse_released() & btn) != BTN_NONE;
-macro Ctx.is_mouse_down(&ctx, MouseButtons btn) => (ctx.mouse_down() & btn) != BTN_NONE;
-
-macro ElemEvents Ctx.get_elem_events(&ctx, Elem *elem)
-{
-	// TODO: add the other events
-	// FIXME: active should be elsewhere
-	bool active = elem.events.mouse_hold || ctx.is_hovered(elem);
-	ElemEvents ev = {
-		.mouse_hover = ctx.is_hovered(elem),
-		.mouse_press = active & ctx.is_mouse_pressed(BTN_ANY),
-		.mouse_release = active & ctx.is_mouse_released(BTN_ANY),
-		.mouse_hold = active & ctx.is_mouse_down(BTN_ANY),
-	};
-	return ev;
-}
-
-// Mouse Button moved
-fn void Ctx.input_mouse_button(&ctx, MouseButtons buttons)
-{
-	ctx.input.mouse.updated = ctx.input.mouse.down ^ buttons;
-	ctx.input.mouse.down = buttons;
-	ctx.input.events.mouse_btn = true;
-}
-
-// Mouse was moved, report absolute position
-fn void Ctx.input_mouse_abs(&ctx, short x, short y)
-{
-	ctx.input.mouse.pos.x = clamp(x, 0u16, ctx.width);
-	ctx.input.mouse.pos.y = clamp(y, 0u16, ctx.height);
-
-	short dx, dy;
-	dx = x - ctx.input.mouse.pos.x;
-	dy = y - ctx.input.mouse.pos.y;
-
-	ctx.input.mouse.delta.x = dx;
-	ctx.input.mouse.delta.y = dy;
-
-	ctx.input.events.mouse_move = true;
-}
-
-// Mouse was moved, report relative motion
-fn void Ctx.input_mouse_delta(&ctx, short dx, short dy)
-{
-	ctx.input.mouse.delta.x = dx;
-	ctx.input.mouse.delta.y = dy;
-
-	short mx, my;
-	mx = ctx.input.mouse.pos.x + dx;
-	my = ctx.input.mouse.pos.y + dy;
-
-	ctx.input.mouse.pos.x = clamp(mx, 0u16, ctx.width);
-	ctx.input.mouse.pos.y = clamp(my, 0u16, ctx.height);
-
-	ctx.input.events.mouse_move = true;
-}

src/ugui_layout.c3

@@ -1,177 +0,0 @@
-module ugui;
-
-
-fn void! Ctx.layout_set_row(&ctx)
-{
-	Id parent_id = ctx.tree.get(ctx.active_div)!;
-	Elem *parent = ctx.cache.search(parent_id)!;
-
-	if (parent.type != ETYPE_DIV) {
-		// what?
-		return UgError.UNEXPECTED_ELEMENT?;
-	}
-
-	parent.div.layout = LAYOUT_ROW;
-}
-
-fn void! Ctx.layout_set_column(&ctx)
-{
-	Id parent_id = ctx.tree.get(ctx.active_div)!;
-	Elem *parent = ctx.cache.search(parent_id)!;
-
-	if (parent.type != ETYPE_DIV) {
-		// what?
-		return UgError.UNEXPECTED_ELEMENT?;
-	}
-
-	parent.div.layout = LAYOUT_COLUMN;
-}
-
-fn void! Ctx.layout_set_floating(&ctx)
-{
-	Id parent_id = ctx.tree.get(ctx.active_div)!;
-	Elem *parent = ctx.cache.search(parent_id)!;
-
-	if (parent.type != ETYPE_DIV) {
-		// what?
-		return UgError.UNEXPECTED_ELEMENT?;
-	}
-
-	parent.div.layout = LAYOUT_FLOATING;
-}
-
-fn void! Ctx.layout_next_row(&ctx)
-{
-	Id parent_id = ctx.tree.get(ctx.active_div)!;
-	Elem *parent = ctx.cache.search(parent_id)!;
-
-	if (parent.type != ETYPE_DIV) {
-		// what?
-		return UgError.UNEXPECTED_ELEMENT?;
-	}
-
-	parent.div.origin_r = Point{
-		.x = parent.bounds.x,
-		.y = parent.div.origin_c.y,
-	};
-	parent.div.origin_c = parent.div.origin_r;
-}
-
-fn void! Ctx.layout_next_column(&ctx)
-{
-	Id parent_id = ctx.tree.get(ctx.active_div)!;
-	Elem *parent = ctx.cache.search(parent_id)!;
-
-	if (parent.type != ETYPE_DIV) {
-		// what?
-		return UgError.UNEXPECTED_ELEMENT?;
-	}
-
-	parent.div.origin_c = Point{
-		.x = parent.div.origin_r.x,
-		.y = parent.bounds.y,
-	};
-	parent.div.origin_r = parent.div.origin_c;
-}
-
-// position the rectangle inside the parent according to the layout
-// parent: parent div
-// rect: the requested size
-// style: apply style
-<*
-@require ctx != null
-@require parent.type == ETYPE_DIV
-*>
-fn Rect Ctx.position_element(&ctx, Elem *parent, Rect rect, bool style = false)
-{
-	Rect placement;
-	Point origin;
-	Div* div = &parent.div;
-
-	// 1. Select the right origin
-	switch (div.layout) {
-	case LAYOUT_ROW:
-		origin = div.origin_r;
-	case LAYOUT_COLUMN:
-		origin = div.origin_c;
-	case LAYOUT_FLOATING: // none
-	default:
-		// Error
-	}
-
-	// the bottom-right border of the element box
-	Point pl_corner;
-
-	// 2. Calculate the placement
-	placement.x = (short)max(origin.x + rect.x, 0);
-	placement.y = (short)max(origin.y + rect.y, 0);
-	placement.w = rect.w > 0 ? rect.w : (short)max(parent.bounds.w - (placement.x - parent.bounds.x), 0);
-	placement.h = rect.h > 0 ? rect.h : (short)max(parent.bounds.h - (placement.y - parent.bounds.y), 0);
-
-	pl_corner.x = placement.x + placement.w;
-	pl_corner.y = placement.y + placement.h;
-
-	// 2.1 apply style, css box model
-	if (style) {
-		Rect margin = ctx.style.margin;
-		Rect border = ctx.style.border;
-		Rect padding = ctx.style.padding;
-
-		placement.x += margin.x;
-		placement.y += margin.y;
-		if (rect.w != 0) { placement.w += border.x+border.w + padding.x+padding.w; }
-		if (rect.h != 0) { placement.h += border.y+border.h + padding.y+padding.h; }
-
-		pl_corner.x = placement.x + placement.w + margin.w;
-		pl_corner.y = placement.y + placement.h + margin.h;
-	}
-
-	// 3. Update the origins of the parent
-	div.origin_r = Point{
-		.x = pl_corner.x,
-		.y = origin.y,
-	};
-	div.origin_c = Point{
-		.x = origin.x,
-		.y = pl_corner.y,
-	};
-
-	// 4. Calculate the "scrolled" view
-	Point off;
-	Rect* cb = &div.children_bounds;
-	if (div.scroll.can_x && div.scroll.on_x) {
-		off.x = (short)(cb.w * div.scroll.value_x);
-	}
-	if (div.scroll.can_y && div.scroll.on_y) {
-		off.y = (short)((float)(cb.h - parent.bounds.h) * div.scroll.value_y);
-	}
-	Rect view = {
-		.x = parent.bounds.x + off.x,
-		.y = parent.bounds.y + off.y,
-		.w = parent.bounds.w,
-		.h = parent.bounds.h,
-	};
-
-	// 5. check if the placement overflows the children ounds, if so update them
-	if (!point_in_rect(pl_corner, *cb)) {
-		if (pl_corner.y > cb.y+cb.h) {
-			cb.h = pl_corner.y - cb.y;
-		}
-		if (pl_corner.x > cb.x+cb.w) {
-			cb.w += pl_corner.x - (cb.x + cb.w);
-		}
-	}
-
-	// 6. check if the placement is inside the view
-	if (rect_collision(placement, view)) {
-		return Rect{
-			.x = placement.x - off.x,
-			.y = placement.y - off.y,
-			.w = placement.w,
-			.h = placement.h,
-		};
-	} else {
-		return Rect{};
-	}
-}
-

src/ugui_slider.c3

@@ -1,108 +0,0 @@
-module ugui;
-
-import std::io;
-
-/*       handle
- * +----+-----+---------------------+
- * |    |#####|                     |
- * +----+-----+---------------------+
- */
-fn ElemEvents! Ctx.slider_hor(&ctx, String label, Rect size)
-{
-    Id id = label.hash();
-
-	Elem *parent = ctx.get_parent()!;
-	Elem *c_elem = ctx.get_elem(id)!;
-	// add it to the tree
-	ctx.tree.add(id, ctx.active_div)!;
-
-	// 1. Fill the element fields
-	c_elem.type = ETYPE_SLIDER;
-
-	// if the element is new or the parent was updated then redo layout
-	if (c_elem.flags.is_new || parent.flags.updated) {
-		// 2. Layout
-		c_elem.bounds = ctx.position_element(parent, size, true);
-		c_elem.slider.handle = Rect{
-			.x = (short)(c_elem.bounds.x + (int)(c_elem.bounds.w*(1.0-0.25) * c_elem.slider.value)),
-			.y = c_elem.bounds.y,
-			.w = (short)(c_elem.bounds.w * 0.25),
-			.h = c_elem.bounds.h,
-		};
-	}
-
-	c_elem.events = ctx.get_elem_events(c_elem);
-	if (parent.flags.has_focus && c_elem.events.mouse_hover) {
-		if (point_in_rect(ctx.input.mouse.pos, c_elem.slider.handle) && c_elem.events.mouse_hold) {
-			short x = (short)clamp(ctx.input.mouse.pos.x - c_elem.slider.handle.w/2, c_elem.bounds.x, c_elem.bounds.x + c_elem.bounds.w - c_elem.slider.handle.w);
-			float v = (float)(c_elem.slider.handle.x-c_elem.bounds.x) / (float)(c_elem.bounds.w-c_elem.slider.handle.w);
-			c_elem.slider.handle.x = x;
-			c_elem.slider.value = v;
-			c_elem.events.update = true;
-		}
-	}
-
-	// Draw the slider background and handle
-	Color bg_color = uint_to_rgba(0x0000ffff);
-	Color handle_color = uint_to_rgba(0x0ff000ff);
-	ctx.push_rect(c_elem.bounds, bg_color)!;
-	ctx.push_rect(c_elem.slider.handle, handle_color)!;
-
-	return c_elem.events;
-}
-
-/*
- * +-+
- * | |
- * | |
- * +-+
- * |#| handle
- * |#|
- * +-+
- * | |
- * | |
- * +-+
- */
-fn ElemEvents! Ctx.slider_ver(&ctx, String label, Rect size)
-{
-	Id id = label.hash();
-
-	Elem *parent = ctx.get_parent()!;
-	Elem *c_elem = ctx.get_elem(id)!;
-	// add it to the tree
-	ctx.tree.add(id, ctx.active_div)!;
-
-	// 1. Fill the element fields
-	c_elem.type = ETYPE_SLIDER;
-
-	// if the element is new or the parent was updated then redo layout
-	if (c_elem.flags.is_new || parent.flags.updated) {
-		// 2. Layout
-		c_elem.bounds = ctx.position_element(parent, size, true);
-		c_elem.slider.handle = Rect{
-			.x = c_elem.bounds.x,
-			.y = (short)(c_elem.bounds.y + (int)(c_elem.bounds.h*(1.0-0.25) * c_elem.slider.value)),
-			.w = c_elem.bounds.w,
-			.h = (short)(c_elem.bounds.h * 0.25),
-		};
-	}
-
-	c_elem.events = ctx.get_elem_events(c_elem);
-	if (parent.flags.has_focus && c_elem.events.mouse_hover) {
-		if (point_in_rect(ctx.input.mouse.pos, c_elem.slider.handle) && c_elem.events.mouse_hold) {
-			short y = (short)clamp(ctx.input.mouse.pos.y - c_elem.slider.handle.h/2, c_elem.bounds.y, c_elem.bounds.y + c_elem.bounds.h - c_elem.slider.handle.h);
-			float v = (float)(c_elem.slider.handle.y-c_elem.bounds.y) / (float)(c_elem.bounds.h-c_elem.slider.handle.h);
-			c_elem.slider.handle.y = y;
-			c_elem.slider.value = v;
-			c_elem.events.update = true;
-		}
-	}
-
-	// Draw the slider background and handle
-	Color bg_color = uint_to_rgba(0x0000ffff);
-	Color handle_color = uint_to_rgba(0x0ff000ff);
-	ctx.push_rect(c_elem.bounds, bg_color)!;
-	ctx.push_rect(c_elem.slider.handle, handle_color)!;
-
-	return c_elem.events;
-}

src/ugui_text.c3

@@ -1,103 +0,0 @@
-module ugui;
-
-import std::io;
-import std::ascii;
-import grapheme;
-
-<*
-@require off != null
-*>
-fn Codepoint str_to_codepoint(char[] str, usz* off)
-{
-	Codepoint cp;
-	isz b = grapheme::decode_utf8(str, str.len, &cp);
-	if (b == 0 || b > str.len) {
-		return 0;
-	}
-	*off = b;
-	return cp;
-}
-
-fn Rect! Ctx.get_text_bounds(&ctx, String text, bool* update_atlas)
-{
-	Rect text_bounds;
-	short line_height = (short)ctx.font.ascender - (short)ctx.font.descender;
-	short line_gap = (short)ctx.font.linegap;
-	text_bounds.h = line_height;
-	Glyph* gp;
-
-	// TODO: account for unicode codepoints
-	short line_len;
-	Codepoint cp;
-	usz off, x;
-	while ((cp = str_to_codepoint(text[off..], &x)) != 0) {
-		off += x;
-		bool n;
-		if (!ascii::is_cntrl((char)cp)) {
-			gp = ctx.font.get_glyph(cp, &n)!;
-			line_len += gp.adv;
-			if (n) { *update_atlas = true; }
-		} else if (cp == '\n'){
-			text_bounds.h += line_height + line_gap;
-			line_len = 0;
-		} else {
-			continue;
-		}
-		if (line_len > text_bounds.w) {
-			text_bounds.w = line_len;
-		}
-	}
-
-	return text_bounds;
-}
-
-fn void! Ctx.text_unbounded(&ctx, String label, String text)
-{
-	Id id = label.hash();
-
-	Elem *parent = ctx.get_parent()!;
-	Elem *c_elem = ctx.get_elem(id)!;
-	// add it to the tree
-	ctx.tree.add(id, ctx.active_div)!;
-
-	// 1. Fill the element fields
-	// this resets the flags
-	c_elem.type = ETYPE_TEXT;
-
-	short baseline = (short)ctx.font.ascender;
-	short line_height = (short)ctx.font.ascender - (short)ctx.font.descender;
-	short line_gap = (short)ctx.font.linegap;
-	bool update_atlas;
-	// if the element is new or the parent was updated then redo layout
-	if (c_elem.flags.is_new || parent.flags.updated) {
-		Rect text_size = ctx.get_text_bounds(text, &update_atlas)!;
-
-		// 2. Layout
-		c_elem.bounds = ctx.position_element(parent, text_size, true);
-
-		// 3. Fill the button specific fields
-		c_elem.text.str = text;
-	}
-
-	if (update_atlas) {
-		// FIXME: atlas here is hardcoded, look at the todo in ugui_data
-		Cmd up = {
-			.type = CMD_UPDATE_ATLAS,
-			.update_atlas = {
-				.raw_buffer = ctx.font.atlas[0].buffer,
-				.width = ctx.font.atlas[0].width,
-				.height = ctx.font.atlas[0].height,
-			},
-		};
-		ctx.cmd_queue.enqueue(&up)!;
-	}
-
-	Cmd bounds = {
-		.type = CMD_RECT,
-		.rect.rect = c_elem.bounds,
-		.rect.color = uint_to_rgba(0x000000ff),
-	};
-	ctx.cmd_queue.enqueue(&bounds)!;
-
-	ctx.push_string(c_elem.bounds, text)!;
-}

test/test_color.c3

@@ -0,0 +1,19 @@
+import std::io;
+
+struct Color { short r,g,b,a; }
+
+macro Color uint.to_rgba(uint u)
+{
+	return Color{
+		.r = (char)((u >> 24) & 0xff),
+		.g = (char)((u >> 16) & 0xff),
+		.b = (char)((u >> 8) & 0xff),
+		.a = (char)((u >> 0) & 0xff)
+	};
+}
+
+fn void main(String[] args)
+{
+	uint col = args[1].to_uint()!!;
+	io::printn(col.to_rgba());
+}

test/test_error.c3

@@ -0,0 +1,72 @@
+import std::io;
+
+struct FaultStack {
+	usz elem;
+	anyfault[16] v;
+}
+
+fn void FaultStack.push(&fs, anyfault f)
+{
+	if (fs.elem < fs.v.len) {
+		fs.v[fs.elem++] = f;
+	}
+}
+
+fn anyfault FaultStack.pop(&fs)
+{
+	return fs.elem > 0 ? fs.v[fs.elem-- - 1] : anyfault{};
+}
+
+FaultStack fs;
+
+fn int! err1()
+{
+	return IoError.OUT_OF_SPACE?;
+}
+
+fn void! err2()
+{
+	return IoError.EOF?;
+}
+
+/*
+macro @unwrap(#f)
+{
+	$if ($typeof(#f).typeid == void!.typeid) {
+		if (catch err = #f) { fs.push(err); }
+		return;
+	} $else {
+		$typeof(#f) x = #f;
+		if (catch err = x) {
+			fs.push(err);
+			return $typeof(#f!!){};
+		} else {return x;}
+	}
+}
+*/
+
+<*
+@require @typekind(#func) == OPTIONAL : `@unwrap requires an optional value`
+*>
+macro @unwrap(#func)
+{
+	anyfault exc = @catch(#func);
+	if (exc != anyfault{}) {
+		fs.push(exc);
+		$if $typeof(#func!!).typeid != void.typeid:
+			return $typeof(#func!!){};
+		$else
+			return;
+		$endif
+	} else {
+		return #func!!;
+	}
+}
+
+fn void main()
+{
+	@unwrap(err1());
+	@unwrap(err2());
+
+	io::printfn("%s", fs.v);
+}

test/test_idgen.c3

@@ -0,0 +1,30 @@
+import std::io;
+
+alias Id = uint;
+
+fn void foo_ex(Id id)
+{
+	io::printfn("id = %d", id);
+}
+
+
+macro Id @compute_id(...)
+{
+	Id id = (Id)$$LINE.hash() ^ (Id)@str_hash($$FILE);
+	$for var $i = 0; $i < $vacount; $i++:
+		id ^= (Id)$vaconst[$i].hash();
+	$endfor
+	return id;
+}
+
+macro foo(...) => foo_ex(@compute_id($vasplat));
+
+fn int main()
+{
+	foo_ex(1234);
+	foo();
+	foo();
+	foo();
+
+	return 0;
+}

test/test_keyboard.c3

@@ -0,0 +1,26 @@
+import rl;
+import std::io;
+
+fn int main(String[] args)
+{
+	short width = 800;
+	short height = 450;
+	rl::set_config_flags(rl::FLAG_WINDOW_RESIZABLE);
+	rl::init_window(width, height, "Ugui Test");
+	rl::set_target_fps(60);
+	rl::enable_event_waiting();
+
+	// Main loop
+	KeyboardKey k;
+	while (!rl::window_should_close()) {
+		do {
+			k = rl::get_char_pressed();
+			io::printfn("%s", k);
+		} while (k != 0);
+	}
+
+	rl::close_window();
+
+	return 0;
+}
+

test_renderer.c3

@@ -0,0 +1,94 @@
+import sdlrenderer::ren;
+import std::io;
+import std::thread;
+import sdl3::sdl;
+import std::compression::qoi;
+import std::core::mem::allocator;
+
+char[*] shader_rect_vert = $embed("resources/shaders/compiled/rect.vert.spv");
+char[*] shader_rect_frag = $embed("resources/shaders/compiled/rect.frag.spv");
+
+char[*] shader_sprite_vert = $embed("resources/shaders/compiled/sprite.vert.spv");
+char[*] shader_sprite_frag = $embed("resources/shaders/compiled/sprite.frag.spv");
+
+const uint WINDOW_WIDTH  = 640;
+const uint WINDOW_HEIGHT = 480;
+
+
+fn int main()
+{
+	ren::Renderer ren;
+	ren.init("test window", WINDOW_WIDTH, WINDOW_HEIGHT);
+
+	// TODO: these could be the same function
+	ren.load_spirv_shader_from_mem("rect shader", &shader_rect_vert, &shader_rect_frag, 0, 0);
+	ren.create_pipeline("rect shader", RECT);
+
+	// load the tux qoi image
+	QOIDesc img_desc;
+	char[] img_pixels = qoi::read(allocator::temp(), "resources/tux.qoi", &img_desc)!!;
+	// and put it in a texture
+	ren.new_texture("tux", FULL_COLOR, img_pixels, img_desc.width, img_desc.height);
+	// create a new pipeline to use the texture
+	ren.load_spirv_shader_from_mem("sprite shader", &shader_sprite_vert, &shader_sprite_frag, 1, 0);
+	ren.create_pipeline("sprite shader", SPRITE);
+
+
+	sdl::Event e;
+	bool quit = false;
+	for (usz i = 0; !quit; i++) {
+
+		if (sdl::poll_event(&e)) {
+			if (e.type == EVENT_QUIT) {
+				quit = true;
+			}
+		}
+
+		if (i == 300) {
+			io::printn("ciao!");
+			img_pixels = qoi::read(allocator::temp(), "resources/tux_inv.qoi", &img_desc)!!;
+			ren.update_texture("tux", img_pixels, img_desc.width, img_desc.height);
+		}
+
+		ren.begin_render(true);
+
+		// Colored Rectangles Render Pass
+		ren.start_render_pass("rect shader");
+
+		// rect 1
+		ren.push_quad(100,100,100,100,0xff00ff00, 20);
+		// rect 2
+		ren.push_quad(0,0,20,20,0xff0000ff);
+		// rect 3
+		ren.push_quad(200,300,50,50,0xffff0000);
+
+		//ren.set_scissor(0,50,200,300);
+
+		ren.draw_quads();
+
+		ren.end_render_pass();
+		// End Rectangle Render Pass
+
+
+		// Textured Rectangles Render Pass
+		ren.start_render_pass("sprite shader");
+		
+		// bind the pipeline's sampler
+		ren.bind_texture("tux");
+
+		// tux
+		ren.push_sprite(300, 0, 54, 64, 0, 0);
+
+		ren.reset_scissor();
+
+		ren.draw_quads();
+
+		ren.end_render_pass();
+		// End Textured Rectangle Render Pass
+
+		ren.end_render();
+	}
+
+	ren.free();
+	return 0;
+}