h
master
Alessandro Mauri 2 years ago
parent 5018ccbbb0
commit 7552d2fa2a
Signed by: alema
GPG Key ID: 2B7BF9531FF03BE8
  1. 18
      text_rendering/font.c
  2. 5
      text_rendering/hash.c
  3. 3
      text_rendering/msdf_c/.gitignore
  4. 8
      text_rendering/msdf_c/CMakeLists.txt
  5. 22
      text_rendering/msdf_c/LICENSE
  6. 27
      text_rendering/msdf_c/Readme.md
  7. 4
      text_rendering/msdf_c/msdf.c
  8. 1395
      text_rendering/msdf_c/msdf.h
  9. BIN
      text_rendering/msdf_c/sample/fonts/Roboto-Regular.ttf
  10. 201
      text_rendering/msdf_c/sample/fonts/RobotoLicense.txt
  11. BIN
      text_rendering/msdf_c/sample/sample
  12. 210
      text_rendering/msdf_c/sample/sample.c
  13. BIN
      text_rendering/msdf_c/sample/sdf.png
  14. 1724
      text_rendering/msdf_c/sample/stb_image_write.h
  15. 110
      text_rendering/msdf_c/sample/svpng.h
  16. 0
      text_rendering/msdf_c/stb_truetype.h

@ -4,7 +4,8 @@
#include <grapheme.h>
#include "stb_truetype.h"
#include "msdf_c/stb_truetype.h"
#include "msdf_c/msdf.h"
#include "util.h"
#include "font.h"
@ -20,9 +21,8 @@
struct font_atlas {
unsigned int glyphs, width, height;
unsigned int glyphs;
unsigned char *atlas;
unsigned int glyph_max_w, glyph_max_h;
struct {
stbtt_fontinfo info;
@ -33,6 +33,10 @@ struct font_atlas {
};
const unsigned int glyph_w = 32;
const unsigned int glyph_h = 32;
// loads a font into memory, storing all the ASCII characters in the atlas
int load_font(struct font_atlas *atlas, const char *path, int height)
{
@ -49,10 +53,10 @@ int load_font(struct font_atlas *atlas, const char *path, int height)
stbtt_GetFontBoundingBox(&(atlas->stb.info), &x0, &y0, &x1, &y1);
baseline = atlas->stb.scale * -y0;
atlas->glyph_max_w = (atlas->stb.scale*x1) - (atlas->stb.scale*x0);
atlas->glyph_max_h = (baseline+atlas->stb.scale*y1) - (baseline+atlas->stb.scale*y0);
atlas->atlas = emalloc(atlas->glyph_max_w*atlas->glyph_max_h*CACHE_SIZE);
//atlas->glyph_max_w = (atlas->stb.scale*x1) - (atlas->stb.scale*x0);
//atlas->glyph_max_h = (baseline+atlas->stb.scale*y1) - (baseline+atlas->stb.scale*y0);
//atlas->atlas = emalloc(atlas->glyph_max_w*atlas->glyph_max_h*CACHE_SIZE);
atlas->atlas
return 0;
}

@ -6,6 +6,7 @@
#include <string.h>
#include "hash.h"
#include "util.h"
#define MAXSIZE 4096
@ -27,7 +28,7 @@ struct hm_ref * hm_create(unsigned int size)
size = 1<<__builtin_clz(size);
// FIXME: check for intger overflow here
struct hm_ref *h = malloc(sizeof(struct hm_ref)+sizeof(struct hm_entry)*size);
struct hm_ref *h = emalloc(sizeof(struct hm_ref)+sizeof(struct hm_entry)*size);
if (h) {
h->items = 0;
h->size = size;
@ -39,7 +40,7 @@ struct hm_ref * hm_create(unsigned int size)
void hm_destroy(struct hm_ref *hm)
{
free(hm);
efree(hm);
}

@ -0,0 +1,3 @@
build
.vscode
.DS_Store

@ -0,0 +1,8 @@
cmake_minimum_required(VERSION 3.19)
project(engine)
add_definitions(-DSAMPLE_ROOT="${PROJECT_SOURCE_DIR}/sample")
set(CMAKE_C_STANDARD 11)
add_executable(msdf_sample sample/sample.c)

@ -0,0 +1,22 @@
MIT License
Copyright (c) 2023 Peter Jakobs
Copyright (c) 2018 exezin
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

@ -0,0 +1,27 @@
# msdf_c 0.1
A pure C99 multi-channel signed distance field generator. Handles MSDF bitmap
Generation from given ttf/otf font (outlines).
Single Header STB-style library
---
[This library is my take on improving msdf-c with some fixes and improving its API](https://github.com/solenum/msdf-c)
[Based on the C++ implementation by Viktor Chlumský.](https://github.com/Chlumsky/msdfgen)
~~~
// example fragment shader
// scale is render_width/glyph_width
// render_width being the width of each rendered glyph
float median(float r, float g, float b) {
return max(min(r, g), min(max(r, g), b));
}
void main()
{
vec3 sample = texture(u_texture, uv).rgb;
float dist = scale * (median(sample.r, sample.g, sample.b) - 0.5);
float o = clamp(dist + 0.5, 0.0, 1.0);
color = vec4(vec3(1.0), o);
}
~~~

@ -0,0 +1,4 @@
#define STB_TRUETYPE_IMPLEMENTATION
#include "stb_truetype.h"
#define MSDF_IMPLEMENTATION
#include "msdf.h"

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@ -0,0 +1,201 @@
Apache License
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@ -0,0 +1,210 @@
//#include "svpng.h"
#define STB_IMAGE_WRITE_IMPLEMENTATION
#include "stb_image_write.h"
#define STB_TRUETYPE_IMPLEMENTATION
#include "../stb_truetype.h"
#define MSDF_IMPLEMENTATION
#include "../msdf.h"
#include "stdio.h"
#ifndef SAMPLE_ROOT
#define SAMPLE_ROOT ""
#endif
typedef struct Range {
void* content;
size_t size;
} Range;
Range g_fileRead(const char* fileName) {
Range range = {NULL, 0};
FILE* fileHandle = fopen(fileName, "rb");
if (fileHandle == NULL) {
assert(!"File not fount");
return range;
}
fseek(fileHandle, 0, SEEK_END); // seek to end of file
size_t size = ftell(fileHandle); // get current file pointer
fseek(fileHandle, 0, SEEK_SET); // seek back to beginning of file
if (size == 0) {
assert(!"File size zero");
return range;
}
void* mem = malloc(size);
size_t readSize = fread(mem, 1, size, fileHandle);
if (readSize == size) {
range.content = mem;
range.size = size;
} else {
free(mem);
}
fclose(fileHandle);
return range;
}
static void* g_alloc(size_t size, void* ctx) {
return malloc(size);
}
static void g_free(void* ptr, void* ctx) {
return free(ptr);
}
float g_min(float a, float b) {
return a > b ? b : a;
}
float g_max(float a, float b) {
return a > b ? a : b;
}
float g_clamp(float val, float min, float max) {
return g_min(g_max(val, min), max);
}
float g_median(float r, float g, float b) {
return g_max(g_min(r, g), g_min(g_max(r, g), b));
}
float g_map(float min, float max, float v) {
return (v - min) / (max - min);
}
int main() {
stbtt_fontinfo stbttInfo;
Range fontFile = g_fileRead("./fonts/Roboto-Regular.ttf");
if (fontFile.content == NULL) {
assert(!"could not load font from disk");
return 1;
}
if (!stbtt_InitFont(&stbttInfo, fontFile.content, stbtt_GetFontOffsetForIndex(fontFile.content, 0))) {
assert(!"Couldn't parse font");
return 1;
}
int ascent, descent;
stbtt_GetFontVMetrics(&stbttInfo, &ascent, &descent, 0);
int borderSize = 4;
int genSize = 32+borderSize;
float genScale = stbtt_ScaleForPixelHeight(&stbttInfo, genSize);
// int glyph = 0x00e8; // è
int glyph = 0x069D;
int glyphIdx = stbtt_FindGlyphIndex(&stbttInfo, glyph);
msdf_AllocCtx allocCtx = {g_alloc, g_free, NULL};
printf("bruh\n");
msdf_Result result;
int success = msdf_genGlyph(&result, &stbttInfo, glyphIdx, borderSize, genScale, 2.0f / genSize, &allocCtx);
if (success == 0) {
assert(!"Failed to generate msdf glyph");
return 1;
}
printf("bruh\n");
// FILE* fp = fopen(SAMPLE_ROOT "/sdf.png", "wb");
uint8_t* pixels = malloc(sizeof(uint8_t) * result.width * result.height * 3);
float scale = genSize;
float maxValue = 1.0 * (scale);
float transistionWidth = ((((((float) genSize) * 0.7f) + scale) / (scale * 2.0f)));
float transistionAbs = (transistionWidth - 0.5);
float transistStart = 0.5 - transistionAbs / 2;
float transistEnd = transistStart + transistionAbs;
//float ff = expf(0.01);
for (int y = 0; y < result.height; y++) {
int yPos = result.width * 3 * y;
uint8_t* pixelRow = pixels + (y * result.width * 3);
for (int x = 0; x < result.width; x++) {
int indexSdf = yPos + (x * 3);
float r = result.rgb[indexSdf + 0];
float g = result.rgb[indexSdf + 1];
float b = result.rgb[indexSdf + 2];
r = ((((r) + scale) / (scale * 2.0f)));
g = ((((g) + scale) / (scale * 2.0f)));
b = ((((b) + scale) / (scale * 2.0f)));
if (r > transistStart) {
if (r > (transistEnd)) {
r = 1.0f;
} else {
r = 0.0f + (r - transistStart) / (transistionAbs);
}
} else {
r = 0.0f;
}
if (g > transistStart) {
if (g > (transistEnd)) {
g = 1.0f;
} else {
g = 0.0f + (g - transistStart) / (transistionAbs);
}
} else {
g = 0.0f;
}
if (b > transistStart) {
if (b > (transistEnd)) {
b = 1.0f;
} else {
b = 0.0f + (b - transistStart) / (transistionAbs);
}
} else {
b = 0.0f;
}
pixelRow[x * 3 + 0] = r * 255.0f; // (r > 0.5f) ? 255.0f : r * 255.0f;
pixelRow[x * 3 + 1] = g * 255.0f; // (g > 0.5f) ? 255.0f : g * 255.0f;
pixelRow[x * 3 + 2] = b * 255.0f; // (b > 0.5f) ? 255.0f : b * 255.0f;
}
}
// printf("bruh\n");
//
// svpng(fp, result.width, result.height, pixels, 0);
stbi_write_png("./sdf.png", result.width, result.height, 3, pixels, 3*result.width);
// fclose(fp);
// apply sdf
//
// FILE* finalImage = fopen(SAMPLE_ROOT "/final.png", "wb");
//
// uint8_t* rgbaFinal = malloc(sizeof(uint8_t) * result.width * result.height * 4);
//
// for (int y = 0; y < result.height; y++) {
// uint8_t* pixelRow = pixels + (y * result.width * 3);
// uint8_t* rgbaFinalRow = rgbaFinal + (y * result.width * 4);
// for (int x = 0; x < result.width; x++) {
// float r = ((float)pixelRow[x * 3 + 0]) / 255.0f;// = r * 255.0f; // (r > 0.5f) ? 255.0f : r * 255.0f;
// float g = ((float)pixelRow[x * 3 + 1]) / 255.0f;// = g * 255.0f; // (g > 0.5f) ? 255.0f : g * 255.0f;
// float b = ((float)pixelRow[x * 3 + 2]) / 255.0f;// = b * 255.0f; // (b > 0.5f) ? 255.0f : b * 255.0f;
// float dist = g_median(r, g, b);
// float opacity = g_clamp(dist - 0.5f, 0, 1) * 2.0f;
// rgbaFinalRow[x * 4 + 0] = 0;//255.0f;
// rgbaFinalRow[x * 4 + 1] = 0;//255.0f;
// rgbaFinalRow[x * 4 + 2] = 0;//255.0f;
// rgbaFinalRow[x * 4 + 3] = opacity * 255.0f;
//
// }
// }
// svpng(finalImage, result.width, result.height, rgbaFinal, 1);
// fclose(finalImage);
return 0;
}

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/*
Copyright (C) 2017 Milo Yip. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice, this
list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
* Neither the name of pngout nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*! \file
\brief svpng() is a minimalistic C function for saving RGB/RGBA image into uncompressed PNG.
\author Milo Yip
\version 0.1.1
\copyright MIT license
\sa http://github.com/miloyip/svpng
*/
#ifndef SVPNG_INC_
#define SVPNG_INC_
/*! \def SVPNG_LINKAGE
\brief User customizable linkage for svpng() function.
By default this macro is empty.
User may define this macro as static for static linkage,
and/or inline in C99/C++, etc.
*/
#ifndef SVPNG_LINKAGE
#define SVPNG_LINKAGE
#endif
/*! \def SVPNG_OUTPUT
\brief User customizable output stream.
By default, it uses C file descriptor and fputc() to output bytes.
In C++, for example, user may use std::ostream or std::vector instead.
*/
#ifndef SVPNG_OUTPUT
#include <stdio.h>
#define SVPNG_OUTPUT FILE* fp
#endif
/*! \def SVPNG_PUT
\brief Write a byte
*/
#ifndef SVPNG_PUT
#define SVPNG_PUT(u) fputc(u, fp)
#endif
/*!
\brief Save a RGB/RGBA image in PNG format.
\param SVPNG_OUTPUT Output stream (by default using file descriptor).
\param w Width of the image. (<16383)
\param h Height of the image.
\param img Image pixel data in 24-bit RGB or 32-bit RGBA format.
\param alpha Whether the image contains alpha channel.
*/
SVPNG_LINKAGE void svpng(SVPNG_OUTPUT, unsigned w, unsigned h, const unsigned char* img, int alpha) {
static const unsigned t[] = { 0, 0x1db71064, 0x3b6e20c8, 0x26d930ac, 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
/* CRC32 Table */ 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c };
unsigned a = 1, b = 0, c, p = w * (alpha ? 4 : 3) + 1, x, y, i; /* ADLER-a, ADLER-b, CRC, pitch */
#define SVPNG_U8A(ua, l) for (i = 0; i < l; i++) SVPNG_PUT((ua)[i]);
#define SVPNG_U32(u) do { SVPNG_PUT((u) >> 24); SVPNG_PUT(((u) >> 16) & 255); SVPNG_PUT(((u) >> 8) & 255); SVPNG_PUT((u) & 255); } while(0)
#define SVPNG_U8C(u) do { SVPNG_PUT(u); c ^= (u); c = (c >> 4) ^ t[c & 15]; c = (c >> 4) ^ t[c & 15]; } while(0)
#define SVPNG_U8AC(ua, l) for (i = 0; i < l; i++) SVPNG_U8C((ua)[i])
#define SVPNG_U16LC(u) do { SVPNG_U8C((u) & 255); SVPNG_U8C(((u) >> 8) & 255); } while(0)
#define SVPNG_U32C(u) do { SVPNG_U8C((u) >> 24); SVPNG_U8C(((u) >> 16) & 255); SVPNG_U8C(((u) >> 8) & 255); SVPNG_U8C((u) & 255); } while(0)
#define SVPNG_U8ADLER(u) do { SVPNG_U8C(u); a = (a + (u)) % 65521; b = (b + a) % 65521; } while(0)
#define SVPNG_BEGIN(s, l) do { SVPNG_U32(l); c = ~0U; SVPNG_U8AC(s, 4); } while(0)
#define SVPNG_END() SVPNG_U32(~c)
SVPNG_U8A("\x89PNG\r\n\32\n", 8); /* Magic */
SVPNG_BEGIN("IHDR", 13); /* IHDR chunk { */
SVPNG_U32C(w); SVPNG_U32C(h); /* Width & Height (8 bytes) */
SVPNG_U8C(8); SVPNG_U8C(alpha ? 6 : 2); /* Depth=8, Color=True color with/without alpha (2 bytes) */
SVPNG_U8AC("\0\0\0", 3); /* Compression=Deflate, Filter=No, Interlace=No (3 bytes) */
SVPNG_END(); /* } */
SVPNG_BEGIN("IDAT", 2 + h * (5 + p) + 4); /* IDAT chunk { */
SVPNG_U8AC("\x78\1", 2); /* Deflate block begin (2 bytes) */
for (y = 0; y < h; y++) { /* Each horizontal line makes a block for simplicity */
SVPNG_U8C(y == h - 1); /* 1 for the last block, 0 for others (1 byte) */
SVPNG_U16LC(p); SVPNG_U16LC(~p); /* Size of block in little endian and its 1's complement (4 bytes) */
SVPNG_U8ADLER(0); /* No filter prefix (1 byte) */
for (x = 0; x < p - 1; x++, img++)
SVPNG_U8ADLER(*img); /* Image pixel data */
}
SVPNG_U32C((b << 16) | a); /* Deflate block end with adler (4 bytes) */
SVPNG_END(); /* } */
SVPNG_BEGIN("IEND", 0); SVPNG_END(); /* IEND chunk {} */
}
#endif /* SVPNG_INC_ */
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