gfx/cairo/win32-cleartype-clipping.patch@6474c204b198
gfx/cairo/win32-cleartype-clipping.patch
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
1 diff --git a/gfx/cairo/cairo/src/cairo-win32-font.c b/gfx/cairo/cairo/src/cairo-win32-font.c
2 --- a/gfx/cairo/cairo/src/cairo-win32-font.c
3 +++ b/gfx/cairo/cairo/src/cairo-win32-font.c
4 @@ -986,6 +986,19 @@ _cairo_win32_scaled_font_init_glyph_metr
5 &metrics, 0, NULL, &matrix) == GDI_ERROR) {
6 status = _cairo_win32_print_gdi_error ("_cairo_win32_scaled_font_init_glyph_metrics:GetGlyphOutlineW");
7 memset (&metrics, 0, sizeof (GLYPHMETRICS));
8 + } else {
9 + if (metrics.gmBlackBoxX > 0 && scaled_font->base.options.antialias != CAIRO_ANTIALIAS_NONE) {
10 + /* The bounding box reported by Windows supposedly contains the glyph's "black" area;
11 + * however, antialiasing (especially with ClearType) means that the actual image that
12 + * needs to be rendered may "bleed" into the adjacent pixels, mainly on the right side.
13 + * To avoid clipping the glyphs when drawn by _cairo_surface_fallback_show_glyphs,
14 + * for example, or other code that uses glyph extents to determine the area to update,
15 + * we add a pixel of "slop" to left side of the nominal "black" area returned by GDI,
16 + * and two pixels to the right (as tests show some glyphs bleed into this column).
17 + */
18 + metrics.gmptGlyphOrigin.x -= 1;
19 + metrics.gmBlackBoxX += 3;
20 + }
21 }
22 cairo_win32_scaled_font_done_font (&scaled_font->base);
23 if (status)
