diff options
Diffstat (limited to 'src/core/SkEdge.h')
| -rw-r--r-- | src/core/SkEdge.h | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/src/core/SkEdge.h b/src/core/SkEdge.h index 53678621c3..c36ba246ce 100644 --- a/src/core/SkEdge.h +++ b/src/core/SkEdge.h @@ -14,6 +14,15 @@ #include "SkFDot6.h" #include "SkMath.h" +//#ifdef SK_IGNORE_SETLINE_FIX +#if 1 + #define SkEdge_Compute_DY(top, y0) ((32 - (y0)) & 63) +#else + // This is correct, as it favors the lower-pixel when y0 is on a 1/2 pixel + // boundary, returning 64 instead of the old code, which returns 0. + #define SkEdge_Compute_DY(top, y0) ((top << 6) + 32 - (y0)) +#endif + struct SkEdge { enum Type { kLine_Type, @@ -118,8 +127,9 @@ int SkEdge::setLine(const SkPoint& p0, const SkPoint& p1, int shift) { } SkFixed slope = SkFDot6Div(x1 - x0, y1 - y0); + const int dy = SkEdge_Compute_DY(top, y0); - fX = SkFDot6ToFixed(x0 + SkFixedMul(slope, (32 - y0) & 63)); // + SK_Fixed1/2 + fX = SkFDot6ToFixed(x0 + SkFixedMul(slope, dy)); // + SK_Fixed1/2 fDX = slope; fFirstY = top; fLastY = bot - 1; |