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#version 330 |
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|
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// viewsize.x = viewport width in pixels; viewsize.y = viewport height in pixels |
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uniform vec2 viewsize; |
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// texture uv coordinate in texture space |
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in vec2 texture_coord; |
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uniform sampler2D texture_sampler; |
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|
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out vec4 color; |
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|
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void main() |
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{ |
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color = mix(vec4(0.0f,0.0f,0.0f,1.0f), vec4(1.0f,1.0f,1.0f,1.0f), texture(texture_sampler, texture_coord)) + vec4(1.0f,0.0f,0.0f,1.0f); |
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} |
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#version 330 core |
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|
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// viewsize.x = viewport width in pixels; viewsize.y = viewport height in pixels |
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uniform vec2 viewsize; |
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|
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// both position and and uv are in pixels |
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layout(location = 0) in vec2 position; |
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layout(location = 1) in vec2 uv; |
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|
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out vec2 texture_coord; |
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|
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void main() |
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{ |
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vec4 pos = vec4(position.x, position.y, 0.0f, 1.0f); |
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vec2 v = viewsize / 2; |
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pos.xy = (pos.xy - v) / v; |
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|
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gl_Position = pos; |
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texture_coord = uv / viewsize; |
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} |
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@ -1,3 +0,0 @@ |
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build |
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.vscode |
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.DS_Store |
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@ -1,27 +0,0 @@ |
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# msdf_c 0.1 |
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A pure C99 multi-channel signed distance field generator. Handles MSDF bitmap |
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Generation from given ttf/otf font (outlines). |
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Single Header STB-style library |
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|
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--- |
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|
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[This library is my take on improving msdf-c with some fixes and improving its API](https://github.com/solenum/msdf-c) |
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|
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[Based on the C++ implementation by Viktor Chlumský.](https://github.com/Chlumsky/msdfgen) |
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|
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~~~ |
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// example fragment shader |
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// scale is render_width/glyph_width |
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// render_width being the width of each rendered glyph |
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float median(float r, float g, float b) { |
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return max(min(r, g), min(max(r, g), b)); |
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} |
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|
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void main() |
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{ |
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vec3 sample = texture(u_texture, uv).rgb; |
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float dist = scale * (median(sample.r, sample.g, sample.b) - 0.5); |
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float o = clamp(dist + 0.5, 0.0, 1.0); |
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color = vec4(vec3(1.0), o); |
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} |
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~~~ |
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@ -1,4 +0,0 @@ |
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#define STB_TRUETYPE_IMPLEMENTATION |
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#include "stb_truetype.h" |
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#define MSDF_IMPLEMENTATION |
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#include "msdf.h" |
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@ -1,201 +0,0 @@ |
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Apache License |
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Version 2.0, January 2004 |
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Binary file not shown.
@ -1,210 +0,0 @@ |
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//#include "svpng.h"
|
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#define STB_IMAGE_WRITE_IMPLEMENTATION |
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#include "stb_image_write.h" |
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#define STB_TRUETYPE_IMPLEMENTATION |
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#include "../stb_truetype.h" |
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#define MSDF_IMPLEMENTATION |
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#include "../msdf.h" |
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|
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#include "stdio.h" |
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|
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|
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#ifndef SAMPLE_ROOT |
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#define SAMPLE_ROOT "" |
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#endif |
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|
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typedef struct Range { |
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void* content; |
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size_t size; |
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} Range; |
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|
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Range g_fileRead(const char* fileName) { |
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Range range = {NULL, 0}; |
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|
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FILE* fileHandle = fopen(fileName, "rb"); |
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if (fileHandle == NULL) { |
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assert(!"File not fount"); |
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return range; |
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} |
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|
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fseek(fileHandle, 0, SEEK_END); // seek to end of file
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size_t size = ftell(fileHandle); // get current file pointer
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fseek(fileHandle, 0, SEEK_SET); // seek back to beginning of file
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|
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if (size == 0) { |
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assert(!"File size zero"); |
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return range; |
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} |
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|
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void* mem = malloc(size); |
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size_t readSize = fread(mem, 1, size, fileHandle); |
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if (readSize == size) { |
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range.content = mem; |
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range.size = size; |
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} else { |
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free(mem); |
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} |
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fclose(fileHandle); |
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return range; |
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} |
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|
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static void* g_alloc(size_t size, void* ctx) { |
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return malloc(size); |
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} |
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|
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static void g_free(void* ptr, void* ctx) { |
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return free(ptr); |
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} |
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|
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float g_min(float a, float b) { |
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return a > b ? b : a; |
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} |
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|
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float g_max(float a, float b) { |
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return a > b ? a : b; |
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} |
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|
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float g_clamp(float val, float min, float max) { |
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return g_min(g_max(val, min), max); |
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} |
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|
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float g_median(float r, float g, float b) { |
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return g_max(g_min(r, g), g_min(g_max(r, g), b)); |
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} |
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|
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float g_map(float min, float max, float v) { |
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return (v - min) / (max - min); |
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} |
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|
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int main() { |
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stbtt_fontinfo stbttInfo; |
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|
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Range fontFile = g_fileRead("./fonts/Roboto-Regular.ttf"); |
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|
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if (fontFile.content == NULL) { |
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assert(!"could not load font from disk"); |
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return 1; |
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} |
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|
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if (!stbtt_InitFont(&stbttInfo, fontFile.content, stbtt_GetFontOffsetForIndex(fontFile.content, 0))) { |
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assert(!"Couldn't parse font"); |
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return 1; |
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} |
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|
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|
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int ascent, descent; |
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stbtt_GetFontVMetrics(&stbttInfo, &ascent, &descent, 0); |
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|
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int borderSize = 4; |
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int genSize = 32+borderSize; |
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float genScale = stbtt_ScaleForPixelHeight(&stbttInfo, genSize); |
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|
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// int glyph = 0x00e8; // è
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int glyph = 0x069D; |
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int glyphIdx = stbtt_FindGlyphIndex(&stbttInfo, glyph); |
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|
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msdf_AllocCtx allocCtx = {g_alloc, g_free, NULL}; |
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|
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|
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printf("bruh\n"); |
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|
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msdf_Result result; |
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int success = msdf_genGlyph(&result, &stbttInfo, glyphIdx, borderSize, genScale, 2.0f / genSize, &allocCtx); |
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|
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if (success == 0) { |
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assert(!"Failed to generate msdf glyph"); |
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return 1; |
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} |
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printf("bruh\n"); |
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|
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// FILE* fp = fopen(SAMPLE_ROOT "/sdf.png", "wb");
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|
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uint8_t* pixels = malloc(sizeof(uint8_t) * result.width * result.height * 3); |
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float scale = genSize; |
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float maxValue = 1.0 * (scale); |
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float transistionWidth = ((((((float) genSize) * 0.7f) + scale) / (scale * 2.0f))); |
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float transistionAbs = (transistionWidth - 0.5); |
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float transistStart = 0.5 - transistionAbs / 2; |
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float transistEnd = transistStart + transistionAbs; |
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|
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//float ff = expf(0.01);
|
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for (int y = 0; y < result.height; y++) { |
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int yPos = result.width * 3 * y; |
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uint8_t* pixelRow = pixels + (y * result.width * 3); |
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for (int x = 0; x < result.width; x++) { |
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int indexSdf = yPos + (x * 3); |
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float r = result.rgb[indexSdf + 0]; |
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float g = result.rgb[indexSdf + 1]; |
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float b = result.rgb[indexSdf + 2]; |
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|
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|
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r = ((((r) + scale) / (scale * 2.0f))); |
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g = ((((g) + scale) / (scale * 2.0f))); |
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b = ((((b) + scale) / (scale * 2.0f))); |
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|
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if (r > transistStart) { |
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if (r > (transistEnd)) { |
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r = 1.0f; |
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} else { |
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r = 0.0f + (r - transistStart) / (transistionAbs); |
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} |
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} else { |
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r = 0.0f; |
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} |
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if (g > transistStart) { |
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if (g > (transistEnd)) { |
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g = 1.0f; |
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} else { |
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g = 0.0f + (g - transistStart) / (transistionAbs); |
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} |
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} else { |
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g = 0.0f; |
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} |
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if (b > transistStart) { |
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if (b > (transistEnd)) { |
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b = 1.0f; |
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} else { |
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b = 0.0f + (b - transistStart) / (transistionAbs); |
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} |
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} else { |
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b = 0.0f; |
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} |
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|
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pixelRow[x * 3 + 0] = r * 255.0f; // (r > 0.5f) ? 255.0f : r * 255.0f;
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pixelRow[x * 3 + 1] = g * 255.0f; // (g > 0.5f) ? 255.0f : g * 255.0f;
|
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pixelRow[x * 3 + 2] = b * 255.0f; // (b > 0.5f) ? 255.0f : b * 255.0f;
|
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} |
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} |
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// printf("bruh\n");
|
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//
|
||||
// svpng(fp, result.width, result.height, pixels, 0);
|
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stbi_write_png("./sdf.png", result.width, result.height, 3, pixels, 3*result.width); |
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// fclose(fp);
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|
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// apply sdf
|
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//
|
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// FILE* finalImage = fopen(SAMPLE_ROOT "/final.png", "wb");
|
||||
//
|
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// 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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} |
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|
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@ -1,110 +0,0 @@ |
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/*
|
||||
Copyright (C) 2017 Milo Yip. All rights reserved. |
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|
||||
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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