diff options
| author | Kristian Høgsberg <krh@redhat.com> | 2006-06-21 16:22:14 -0400 |
|---|---|---|
| committer | Kristian Høgsberg <krh@redhat.com> | 2006-06-21 16:22:14 -0400 |
| commit | ed18d776f02e2ab235954501ef64936af9f9d909 (patch) | |
| tree | 23e4fef6f6ba7834fea6c2a904a11e734e1ece5f /fb/fbcompose.c | |
| parent | ea5e0eabd1303a55d8fc10f44d21a3d371ce8919 (diff) | |
Fix #2488 for fb too: sample pixel center when transforming.
Diffstat (limited to 'fb/fbcompose.c')
| -rw-r--r-- | fb/fbcompose.c | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/fb/fbcompose.c b/fb/fbcompose.c index 6f7e3e6ec..03adab456 100644 --- a/fb/fbcompose.c +++ b/fb/fbcompose.c @@ -2726,8 +2726,9 @@ static void fbFetchSourcePict(PicturePtr pict, int x, int y, int width, CARD32 * xFixed_32_32 l; xFixed_48_16 dx, dy, a, b, off; - v.vector[0] = IntToxFixed(x); - v.vector[1] = IntToxFixed(y); + /* reference point is the center of the pixel */ + v.vector[0] = IntToxFixed(x) + xFixed1/2; + v.vector[1] = IntToxFixed(y) + xFixed1/2; v.vector[2] = xFixed1; if (pict->transform) { if (!PictureTransformPoint3d (pict->transform, &v)) @@ -2793,8 +2794,9 @@ static void fbFetchSourcePict(PicturePtr pict, int x, int y, int width, CARD32 * if (pict->transform) { PictVector v; - v.vector[0] = IntToxFixed(x); - v.vector[1] = IntToxFixed(y); + /* reference point is the center of the pixel */ + v.vector[0] = IntToxFixed(x) + xFixed1/2; + v.vector[1] = IntToxFixed(y) + xFixed1/2; v.vector[2] = xFixed1; if (!PictureTransformPoint3d (pict->transform, &v)) return; @@ -2914,8 +2916,9 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32 dx = pict->pDrawable->x; dy = pict->pDrawable->y; - v.vector[0] = IntToxFixed(x - dx); - v.vector[1] = IntToxFixed(y - dy); + /* reference point is the center of the pixel */ + v.vector[0] = IntToxFixed(x - dx) + xFixed1 / 2; + v.vector[1] = IntToxFixed(y - dy) + xFixed1 / 2; v.vector[2] = xFixed1; /* when using convolution filters one might get here without a transform */ @@ -3020,6 +3023,12 @@ static void fbFetchTransformed(PicturePtr pict, int x, int y, int width, CARD32 } } } else if (pict->filter == PictFilterBilinear) { + /* adjust vector for maximum contribution at 0.5, 0.5 of each texel. */ + v.vector[0] -= v.vector[2] / 2; + v.vector[1] -= v.vector[2] / 2; + unit.vector[0] -= unit.vector[2] / 2; + unit.vector[1] -= unit.vector[2] / 2; + if (pict->repeatType == RepeatNormal) { if (REGION_NUM_RECTS(pict->pCompositeClip) == 1) { for (i = 0; i < width; ++i) { |