vtgl

Commit: d538eba43dab4578427d7ada3db0542b50e54e22
Parent: edc98a4478a6aa44b1916586cf1f30d5f30f081a
Author: Randy Palamar
Date:   Tue, 12 Nov 2024 06:23:51 -0700

font: try to account for negative x0

really this font code needs a cleanup pass

Diffstat:
M
font.c
 | 
29
+++++++++++++++++------------
M
util.h
 | 
8
++++++--

2 files changed, 23 insertions(+), 14 deletions(-)
diff --git a/font.c b/font.c
@@ -1,4 +1,7 @@
 /* See LICENSE for copyright details */
+#define FONT_H_PADDING      1
+#define FONT_BASELINE_EXTRA 1
+
 static b32
 init_font(Font *f, FontDesc *fdesc)
 {
@@ -213,14 +216,14 @@ render_glyph(Arena *a, FontAtlas *fa, u32 cp, u32 font_id, enum face_style style
 	stbtt_GetGlyphBitmapBoxSubpixel(&f->font_info, glyph_idx, scale, scale, 0, 0,
 	                                &x0, &y0, &x1, &y1);
 
-	i32 height     = y1 - y0;
-	i32 width      = x1 - x0;
+	i32 height  = y1 - y0;
+	i32 width   = x1 - x0;
 
 	stbtt_GetGlyphHMetrics(&f->font_info, glyph_idx, &advance, &left_bearing);
 	cg->advance = scale * advance;
 	cg->height  = height;
 	cg->width   = width;
-	cg->x0      = x0;
+	cg->x0      = x0 + FONT_H_PADDING;
 	cg->y0      = y0;
 
 	u8 *render_buf = alloc(a, u8, width * height);
@@ -275,10 +278,12 @@ render_glyph(Arena *a, FontAtlas *fa, u32 cp, u32 font_id, enum face_style style
 	for (u32 i = 0; i < cg->tile_count; i++)
 		gc->occupied_tiles[tile_index + i] = 1;
 
+	ASSERT(x0 + FONT_H_PADDING >= 0);
+
 	rgba_bitmap = alloc(a, u32, out_size);
 	u32 out_y  = (fa->info.h + y0 - fa->info.baseline) * out_width;
 	for (i32 i = 0; i < height; i++) {
-		u32 out_x = x0;
+		u32 out_x = x0 + FONT_H_PADDING;
 		for (i32 j = 0; j < width; j++) {
 			/* TODO: handled coloured glyphs */
 			u32 pixel = 0;
@@ -316,8 +321,10 @@ font_atlas_update(FontAtlas *fa, iv2 glyph_bitmap_dim)
 	stbtt_GetFontBoundingBox(&font->font_info, &x0, &y0, &x1, &y1);
 	f32 scale         = font->stbtt_scale;
 	fa->info.h        = (u32)(scale * (y1 - y0)) + 1;
-	fa->info.w        = (u32)(scale * (x1 - x0)) + 1;
-	fa->info.baseline = (u32)(-scale * y0) + 1;
+	fa->info.w        = (u32)(scale * (x1 - x0)) + 1 + FONT_H_PADDING;
+	fa->info.baseline = (u32)(-scale * y0) + 1 + FONT_BASELINE_EXTRA;
+
+	ASSERT(FONT_H_PADDING >= (i32)ABS(x0 * scale));
 
 	/* NOTE: sometimes the reported width is wrong; try '_' which is often the widest char */
 	i32 glyph_idx = stbtt_FindGlyphIndex(&font->font_info, '_');
@@ -354,11 +361,9 @@ shift_font_sizes(FontAtlas *fa, i32 size_delta)
 static void
 init_fonts(FontAtlas *fa, Arena *a, iv2 glyph_bitmap_dim)
 {
-	u32 n_fonts   = ARRAY_COUNT(g_fonts);
-
 	fa->nfonts = 0;
-	fa->fonts  = alloc(a, typeof(*fa->fonts), n_fonts);
-	for (u32 j = 0; j < n_fonts; j++) {
+	fa->fonts  = alloc(a, typeof(*fa->fonts), ARRAY_COUNT(g_fonts));
+	for (u32 j = 0; j < ARRAY_COUNT(g_fonts); j++) {
 		b32 result = 0;
 		for (u32 i = 0; i < FS_LAST; i++) {
 			if (!g_fonts[j][i].path)
@@ -381,8 +386,8 @@ init_fonts(FontAtlas *fa, Arena *a, iv2 glyph_bitmap_dim)
 	i32 x0, x1, y0, y1;
 	f32 scale = stbtt_ScaleForPixelHeight(&f->font_info, MIN_FONT_SIZE);
 	stbtt_GetFontBoundingBox(&f->font_info, &x0, &y0, &x1, &y1);
-	i32 h = scale * (y1 - y0) + 0.5;
-	i32 w = scale * (x1 - x0) + 0.5;
+	f32 h = (u32)(scale * (y1 - y0)) + 1;
+	f32 w = (u32)(scale * (x1 - x0)) + 1 + FONT_H_PADDING;
 	i32 max_tiles_x = glyph_bitmap_dim.x / w;
 	i32 max_tiles_y = glyph_bitmap_dim.y / h;
 
diff --git a/util.h b/util.h
@@ -11,6 +11,10 @@
 #define asm __asm__
 #endif
 
+#ifndef typeof
+#define typeof __typeof__
+#endif
+
 #ifndef static_assert
 #define static_assert _Static_assert
 #endif
@@ -356,8 +360,8 @@ typedef struct {
 typedef Font FontFamily[FS_LAST];
 
 typedef struct {
-	u32  h, w;
-	i32  baseline;
+	u32 h, w;
+	i32 baseline;
 } FontInfo;
 
 typedef struct {