1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-07-25 20:57:35 +00:00

LibGfx: Add ability to request glyphs at subpixel offsets to fonts

This adds the option to pass a subpixel offset when fetching a glyph
from a font, this offset is currently snapped to thirds of a pixel
(i.e. 0, 0.33, 0.66). This is then used when rasterizing the glyph,
which is then cached like usual.

Note that when using subpixel offsets you're trading a bit of space
for accuracy. With the current third of a pixel offsets you can end
up with up to 9 bitmaps per glyph.
This commit is contained in:
MacDue 2023-01-02 20:10:00 +01:00 committed by Andreas Kling
parent a1726b1ba5
commit ada48a1daf
14 changed files with 121 additions and 21 deletions

View file

@ -8,6 +8,7 @@
#include <AK/Noncopyable.h>
#include <AK/RefCounted.h>
#include <LibGfx/Font/Font.h>
#include <LibGfx/Forward.h>
namespace Gfx {
@ -36,7 +37,7 @@ public:
virtual ScaledFontMetrics metrics(float x_scale, float y_scale) const = 0;
virtual ScaledGlyphMetrics glyph_metrics(u32 glyph_id, float x_scale, float y_scale) const = 0;
virtual float glyphs_horizontal_kerning(u32 left_glyph_id, u32 right_glyph_id, float x_scale) const = 0;
virtual RefPtr<Gfx::Bitmap> rasterize_glyph(u32 glyph_id, float x_scale, float y_scale) const = 0;
virtual RefPtr<Gfx::Bitmap> rasterize_glyph(u32 glyph_id, float x_scale, float y_scale, GlyphSubpixelOffset) const = 0;
virtual u32 glyph_count() const = 0;
virtual u16 units_per_em() const = 0;
virtual u32 glyph_id_for_code_point(u32 code_point) const = 0;