From 6e6927247359cc0db47501fb9d2dbb7856aa5985 Mon Sep 17 00:00:00 2001 From: Søren Sandmann Pedersen Date: Wed, 27 May 2009 15:51:19 -0400 Subject: Fix alpha map computation in miComputeCompositeRegion() According to the RENDER spec, the origin of the alpha map is interpreted relative to the origin of the drawable of the image, not the origin of the drawable of the alpha map. This commit fixes that and adds an alpha-test.c test program. The only use of alpha maps I have been able to find is in Qt and they don't use a non-zero alpha origin. --- render/mipict.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'render') diff --git a/render/mipict.c b/render/mipict.c index c653ec4f5..e0d40ae34 100644 --- a/render/mipict.c +++ b/render/mipict.c @@ -459,8 +459,8 @@ miComputeCompositeRegion (RegionPtr pRegion, if (pSrc->alphaMap) { if (!miClipPictureSrc (pRegion, pSrc->alphaMap, - xDst - (xSrc + pSrc->alphaOrigin.x), - yDst - (ySrc + pSrc->alphaOrigin.y))) + xDst - (xSrc - pSrc->alphaOrigin.x), + yDst - (ySrc - pSrc->alphaOrigin.y))) { pixman_region_fini (pRegion); return FALSE; @@ -477,8 +477,8 @@ miComputeCompositeRegion (RegionPtr pRegion, if (pMask->alphaMap) { if (!miClipPictureSrc (pRegion, pMask->alphaMap, - xDst - (xMask + pMask->alphaOrigin.x), - yDst - (yMask + pMask->alphaOrigin.y))) + xDst - (xMask - pMask->alphaOrigin.x), + yDst - (yMask - pMask->alphaOrigin.y))) { pixman_region_fini (pRegion); return FALSE; -- cgit v1.2.3