I can't even

text_rendering/font.c

@@ -25,27 +25,22 @@
 // this way the texture atlas for the font will be bigger but we save up the space
 // needed for rendering the font in multiple sizes
 
-
-struct font_atlas {
-	unsigned int glyphs, width, height;
-	unsigned char *atlas;
-
-	struct {
-		stbtt_fontinfo stb;
-		msdf_AllocCtx ctx;
-		msdf_Result msdf;
-		float scale;
-	} priv;
-
-	int file_size;
-	unsigned char *file;
-};
+// as of now only monospaced fonts work correctly since no kerning information is stored 
 
 
 const unsigned int glyph_w = 32;
 const unsigned int glyph_h = 32;
 
 
+struct priv {
+	stbtt_fontinfo stb;
+	msdf_AllocCtx ctx;
+	msdf_Result msdf;
+	float scale;
+};
+#define PRIV(x) ((struct priv *)x->priv)
+
+
 // only useful for msdf_c
 static inline void * _emalloc(size_t x, void *_) { (void)_; return emalloc(x); }
 static inline void _efree(void *x, void *_) { (void)_; efree(x); }
@@ -53,7 +48,11 @@ static inline void _efree(void *x, void *_) { (void)_; efree(x); }
 
 struct font_atlas * font_init(void)
 {
-	return emalloc(sizeof(struct font_atlas));
+	struct font_atlas *p = emalloc(sizeof(struct font_atlas));
+	memset(p, 0, sizeof(struct font_atlas));
+	p->priv = emalloc(sizeof(struct priv));
+	memset(p->priv, 0, sizeof(struct priv));
+	return p;
 }
 
 
@@ -67,28 +66,35 @@ int font_load(struct font_atlas *atlas, const char *path)
 
 	dump_file(path, &(atlas->file), &(atlas->file_size));
 
-	err = stbtt_InitFont(&(atlas->priv.stb), atlas->file, 0);
+	err = stbtt_InitFont(&(PRIV(atlas)->stb), (unsigned char *)atlas->file, 0);
 	ERROR(err == 0, -1);
 
-	atlas->priv.scale = stbtt_ScaleForPixelHeight(&(atlas->priv.stb), glyph_h);
+	PRIV(atlas)->scale = stbtt_ScaleForPixelHeight(&(PRIV(atlas)->stb), glyph_h);
 	//int ascent, descent, linegap, baseline;
 	//int x0,y0,x1,y1;
-	//stbtt_GetFontVMetrics(&(atlas->priv.stb), &ascent, &descent, &linegap);
-	//stbtt_GetFontBoundingBox(&(atlas->priv.stb), &x0, &y0, &x1, &y1);
-	//baseline = atlas->priv.scale * -y0;
-	//atlas->glyph_max_w = (atlas->priv.scale*x1) - (atlas->priv.scale*x0);
-	//atlas->glyph_max_h = (baseline+atlas->priv.scale*y1) - (baseline+atlas->priv.scale*y0);
+	//stbtt_GetFontVMetrics(&(PRIV(atlas)->stb), &ascent, &descent, &linegap);
+	//stbtt_GetFontBoundingBox(&(PRIV(atlas)->stb), &x0, &y0, &x1, &y1);
+	//baseline = PRIV(atlas)->scale * -y0;
+	//atlas->glyph_max_w = (PRIV(atlas)->scale*x1) - (PRIV(atlas)->scale*x0);
+	//atlas->glyph_max_h = (baseline+PRIV(atlas)->scale*y1) - (baseline+PRIV(atlas)->scale*y0);
 	//atlas->atlas = emalloc(atlas->glyph_max_w*atlas->glyph_max_h*CACHE_SIZE);
 
-	atlas->atlas  = ecalloc(CACHE_SIZE, BDEPTH*glyph_h*glyph_w);
+	atlas->atlas  = emalloc(CACHE_SIZE*BDEPTH*glyph_h*glyph_w);
 	memset(atlas->atlas, 0, CACHE_SIZE*BDEPTH*glyph_h*glyph_w);
-	atlas->width  = glyph_w*CACHE_SIZE/2;
-	atlas->height = glyph_h*CACHE_SIZE/2;
+	// FIXME: make this a square atlas
+	atlas->width  = glyph_w*CACHE_SIZE/4;
+	atlas->height = glyph_h*4;
 
-	atlas->priv.ctx = (msdf_AllocCtx){_emalloc, _efree, NULL};
+	PRIV(atlas)->ctx = (msdf_AllocCtx){_emalloc, _efree, NULL};
 
 	cache_init();
 
+	// preallocate all ascii characters
+	for (char c = ' '; c <= '~'; c++) {
+		if (!font_get_glyph_texture(atlas, c, NULL))
+			return -1;
+	}
+
 	return 0;
 }
 
@@ -97,6 +103,7 @@ int font_free(struct font_atlas *atlas)
 {
 	efree(atlas->atlas);
 	efree(atlas->file);
+	efree(atlas->priv);
 	efree(atlas);
 	cache_destroy();
 	return 0;
@@ -105,33 +112,38 @@ int font_free(struct font_atlas *atlas)
 
 // FIXME: when generating the sdf I only use the height, so to not encounter memory
 //        errors height and width must be equal
-const struct font_glyph * font_get_glyph_texture(struct font_atlas *atlas, unsigned int code)
+const struct font_glyph * font_get_glyph_texture(struct font_atlas *atlas, unsigned int code, int *updated)
 {
-	const struct font_glyph *r;
-	if ((r = cache_search(code)) != NULL)
-		return r;
+	int u = 0;
+	if (!updated) updated = &u;
 
+	const struct font_glyph *r;
+	if ((r = cache_search(code)) != NULL) {
+		*updated = 0;
+		return r;
+	}
+
+	*updated = 1;
 	// generate the sdf and put it into the cache
 	// TODO: generate the whole block at once
-	int idx = stbtt_FindGlyphIndex(&atlas->priv.stb, code);
+	int idx = stbtt_FindGlyphIndex(&PRIV(atlas)->stb, code);
 	// FIXME: what happens if I change the range?
 	int err;
-	err = msdf_genGlyph(&atlas->priv.msdf,
-		&atlas->priv.stb,
+	err = msdf_genGlyph(&PRIV(atlas)->msdf,
+		&PRIV(atlas)->stb,
 		idx,
 		BORDER,
-		atlas->priv.scale,
+		PRIV(atlas)->scale,
 		2.0f/glyph_h,
-		&atlas->priv.ctx);
+		&PRIV(atlas)->ctx);
 	// msdf_genGlyph returns 0 only when there are no contours, so only for
 	// whitespace and such, for those insert a zero uv map into the cache
 	// FIXME: this is a waste of space
 	if (!err) {
-		atlas->priv.msdf.width = 0;
-		atlas->priv.msdf.height = 0;
+		PRIV(atlas)->msdf.width = 0;
+		PRIV(atlas)->msdf.height = 0;
 	}
 
-
 	unsigned int spot = cache_get();
 	unsigned int oy   = (glyph_h * spot) / atlas->width;
 	unsigned int ox   = (glyph_h * spot) % atlas->height;
@@ -139,7 +151,7 @@ const struct font_glyph * font_get_glyph_texture(struct font_atlas *atlas, unsig
 
 	// sum magic shit
 	struct {unsigned char r,g,b;} *a = (void *)atlas->atlas;
-	msdf_Result  *res = &atlas->priv.msdf;
+	msdf_Result  *res = &PRIV(atlas)->msdf;
 	float s  = glyph_h;
 	float tw = ((s * 0.7f) + s) / (s * 2.0f);
 	float ta = tw - 0.5f;
@@ -178,7 +190,11 @@ const struct font_glyph * font_get_glyph_texture(struct font_atlas *atlas, unsig
 		.w = res->width,
 		.h = res->height,
 	};
-	return cache_insert(&g, spot);
+	const struct font_glyph *ret = cache_insert(&g, spot);
+
+	efree(PRIV(atlas)->msdf.rgb);
+
+	return ret;
 }
 
 
@@ -186,9 +202,8 @@ void font_dump(const struct font_atlas *atlas, const char *path)
 {
 	stbi_write_png(
 		path,
-		//atlas->width,
-		//atlas->height,
-		128, 128,
+		atlas->width,
+		atlas->height,
 		BDEPTH,
 		atlas->atlas,
 		BDEPTH*atlas->width);