image: Round down when rendering antialiased boxes

Matches Pixman's output when going via pixman_rasterize_trapezoid()

1 files changed, 6 insertions, 0 deletions

diff --git a/src/cairo-fixed-private.h b/src/cairo-fixed-private.h
index 75ecc06dc..b30879438 100644
--- a/src/cairo-fixed-private.h
+++ b/src/cairo-fixed-private.h
@@ -166,6 +166,12 @@ _cairo_fixed_integer_round (cairo_fixed_t f)
 }
 
 static inline int
+_cairo_fixed_integer_round_down (cairo_fixed_t f)
+{
+    return (f + CAIRO_FIXED_FRAC_MASK/2) >> CAIRO_FIXED_FRAC_BITS;
+}
+
+static inline int
 _cairo_fixed_fractional_part (cairo_fixed_t f)
 {
     return f & CAIRO_FIXED_FRAC_MASK;