Bug 329547 – pango_layout_get_pixel_extents and

2006-04-29  Behdad Esfahbod  <behdad@gnome.org>

        Bug 329547 – pango_layout_get_pixel_extents and
        pango_layout_get_pixel_size cause off-by-one metrics

        * docs/pango-sections.txt:
        * docs/tmpl/glyphs.sgml:
        * pango/pango-types.h: Define PANGO_PIXELS_FLOOR and
        * PANGO_PIXELS_CEIL.

        * pango/pango-layout.c (pango_layout_get_pixel_extents),
        (pango_layout_get_pixel_size): Make sure logical rects are
        consistent and ink rects are inclusive.

1 files changed, 6 insertions, 4 deletions

diff --git a/pango/pango-types.h b/pango/pango-types.h
index 6a198a60..980658a3 100644
--- a/pango/pango-types.h
+++ b/pango/pango-types.h
@@ -127,10 +127,12 @@ double pango_matrix_get_font_scale_factor (const PangoMatrix *matrix);
 
 #define PANGO_SCALE 1024
 #define PANGO_PIXELS(d) (((int)(d) + 512) >> 10)
-/* The above expression is just slightly wrong for floating point d;
- * We'd expect -512.5 => -1 but instead we get 0. That's unlikely
- * to matter for practical use and the expression is much more
- * compact and faster than alternatives that work exactly for both
+#define PANGO_PIXELS_FLOOR(d) (((int)(d)) >> 10)
+#define PANGO_PIXELS_CEIL(d) (((int)(d) + 1023) >> 10)
+/* The above expressions are just slightly wrong for floating point d;
+ * For example we'd expect PANGO_PIXELS(-512.5) => -1 but instead we get 0.
+ * That's unlikely to matter for practical use and the expression is much
+ * more compact and faster than alternatives that work exactly for both
  * integers and floating point.
  */