Readd kerning

2 files changed, 26 insertions, 14 deletions

diff --git a/src/graphics/font.c b/src/graphics/font.c
index 1c3631d..17362f6 100644
--- a/src/graphics/font.c
+++ b/src/graphics/font.c
@@ -228,8 +228,6 @@ int mgl_font_get_glyph(mgl_font *self, uint32_t codepoint, mgl_font_glyph *glyph
     return res;
 }
 
-int mgl_font_get_kerning(const mgl_font *self, uint32_t prev_codepoint, uint32_t codepoint) {
-    return 0;
-    /* TODO: */
-    /*return stbtt_GetCodepointKernAdvance(self->font_info, prev_codepoint, codepoint);*/
+float mgl_font_get_kerning(const mgl_font *self, uint32_t prev_codepoint, uint32_t codepoint) {
+    return stbtt_GetCodepointKernAdvance(self->font_info, prev_codepoint, codepoint) * stbtt_ScaleForPixelHeight(self->font_info, self->character_size);
 }
diff --git a/src/graphics/text.c b/src/graphics/text.c
index cd9d0d9..3620659 100644
--- a/src/graphics/text.c
+++ b/src/graphics/text.c
@@ -36,6 +36,7 @@ static void mgl_text_for_each_codepoint(const mgl_text *self, codepoint_loop_cal
                     return;
             }
         }
+
         i += clen;
         ++codepoint_index;
     }
@@ -49,21 +50,26 @@ typedef struct {
     mgl_vec2f bounds;
     float line_width;
     const mgl_font *font;
+    uint32_t prev_codepoint;
 } CalculateBoundsUserdata;
 
 static bool calculate_bounds_callback(size_t codepoint_index, uint32_t codepoint, const mgl_font_glyph *glyph, void *userdata) {
     (void)codepoint_index;
+
     CalculateBoundsUserdata *calculate_bounds_userdata = userdata;
     if(codepoint == '\t') {
-        calculate_bounds_userdata->line_width += (glyph->advance * TAB_WIDTH);
+        calculate_bounds_userdata->line_width += (glyph->advance * TAB_WIDTH) + mgl_font_get_kerning(calculate_bounds_userdata->font, calculate_bounds_userdata->prev_codepoint, codepoint);
         calculate_bounds_userdata->bounds.x = max_float(calculate_bounds_userdata->bounds.x, calculate_bounds_userdata->line_width);
     } else if(codepoint == '\n') {
         calculate_bounds_userdata->line_width = 0.0f;
         calculate_bounds_userdata->bounds.y += calculate_bounds_userdata->font->character_size;
+        calculate_bounds_userdata->prev_codepoint = 0;
     } else {
-        calculate_bounds_userdata->line_width += glyph->advance;
+        calculate_bounds_userdata->line_width += glyph->advance + mgl_font_get_kerning(calculate_bounds_userdata->font, calculate_bounds_userdata->prev_codepoint, codepoint);
         calculate_bounds_userdata->bounds.x = max_float(calculate_bounds_userdata->bounds.x, calculate_bounds_userdata->line_width);
     }
+
+    calculate_bounds_userdata->prev_codepoint = codepoint;
     return true;
 }
 
@@ -73,6 +79,7 @@ static mgl_vec2f mgl_text_calculate_bounds(mgl_text *self) {
     calculate_bounds_userdata.bounds.y = self->font->character_size;
     calculate_bounds_userdata.line_width = 0.0f;
     calculate_bounds_userdata.font = self->font;
+    calculate_bounds_userdata.prev_codepoint = 0;
     mgl_text_for_each_codepoint(self, calculate_bounds_callback, &calculate_bounds_userdata);
     return calculate_bounds_userdata.bounds;
 }
@@ -126,9 +133,10 @@ mgl_vec2f mgl_text_get_bounds(const mgl_text *self) {
 }
 
 typedef struct {
-    mgl_vec2i position;
+    mgl_vec2f position;
     const mgl_text *text;
     size_t index;
+    uint32_t prev_codepoint;
 } FindCharacterPosUserdata;
 
 static bool find_character_pos_callback(size_t codepoint_index, uint32_t codepoint, const mgl_font_glyph *glyph, void *userdata) {
@@ -137,21 +145,23 @@ static bool find_character_pos_callback(size_t codepoint_index, uint32_t codepoi
         return false;
 
     if(codepoint == '\t') {
-        find_character_pos_userdata->position.x += (glyph->advance * TAB_WIDTH);
+        find_character_pos_userdata->position.x += (glyph->advance * TAB_WIDTH) + mgl_font_get_kerning(find_character_pos_userdata->text->font, find_character_pos_userdata->prev_codepoint, codepoint);
     } else if(codepoint == '\n') {
         find_character_pos_userdata->position.x = find_character_pos_userdata->text->position.x;
         find_character_pos_userdata->position.y += find_character_pos_userdata->text->font->character_size;
+        find_character_pos_userdata->prev_codepoint = 0;
     } else {
-        find_character_pos_userdata->position.x += glyph->advance;
+        find_character_pos_userdata->position.x += glyph->advance + mgl_font_get_kerning(find_character_pos_userdata->text->font, find_character_pos_userdata->prev_codepoint, codepoint);
     }
     return true;
 }
 
 mgl_vec2f mgl_text_find_character_pos(mgl_text *self, size_t index) {
     FindCharacterPosUserdata find_character_pos_userdata;
-    find_character_pos_userdata.position = (mgl_vec2i){ self->position.x, self->position.y };
+    find_character_pos_userdata.position = self->position;
     find_character_pos_userdata.text = self;
     find_character_pos_userdata.index = index;
+    find_character_pos_userdata.prev_codepoint = 0;
     mgl_text_for_each_codepoint(self, find_character_pos_callback, &find_character_pos_userdata);
     return (mgl_vec2f){ find_character_pos_userdata.position.x, find_character_pos_userdata.position.y };
 }
@@ -171,21 +181,24 @@ static void mgl_text_draw_glyph(mgl_context *context, const mgl_font_glyph *glyp
 }
 
 typedef struct {
-    mgl_vec2i position;
+    mgl_vec2f position;
     const mgl_text *text;
     mgl_context *context;
+    uint32_t prev_codepoint;
 } TextDrawUserdata;
 
 static bool text_draw_callback(size_t codepoint_index, uint32_t codepoint, const mgl_font_glyph *glyph, void *userdata) {
     (void)codepoint_index;
     TextDrawUserdata *text_draw_userdata = userdata;
     if(codepoint == '\t') {
-        text_draw_userdata->position.x += (glyph->advance * TAB_WIDTH);
+        text_draw_userdata->position.x += (glyph->advance * TAB_WIDTH) + mgl_font_get_kerning(text_draw_userdata->text->font, text_draw_userdata->prev_codepoint, codepoint);
     } else if(codepoint == '\n') {
         text_draw_userdata->position.x = text_draw_userdata->text->position.x;
         text_draw_userdata->position.y += text_draw_userdata->text->font->character_size;
+        text_draw_userdata->prev_codepoint = 0;
     } else {
-        mgl_text_draw_glyph(text_draw_userdata->context, glyph, text_draw_userdata->position);
+        text_draw_userdata->position.x += mgl_font_get_kerning(text_draw_userdata->text->font, text_draw_userdata->prev_codepoint, codepoint);
+        mgl_text_draw_glyph(text_draw_userdata->context, glyph, (mgl_vec2i){ text_draw_userdata->position.x, text_draw_userdata->position.y });
         text_draw_userdata->position.x += glyph->advance;
     }
     return true;
@@ -198,9 +211,10 @@ void mgl_text_draw(mgl_context *context, mgl_text *text) {
         return;
 
     TextDrawUserdata text_draw_userdata;
-    text_draw_userdata.position = (mgl_vec2i){ text->position.x, text->position.y + text->font->character_size };
+    text_draw_userdata.position = (mgl_vec2f){ text->position.x, text->position.y + text->font->character_size };
     text_draw_userdata.text = text;
     text_draw_userdata.context = context;
+    text_draw_userdata.prev_codepoint = 0;
 
     context->gl.glColor4ub(text->color.r, text->color.g, text->color.b, text->color.a);
     mgl_texture_use(&text->font->texture);