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Merge branch 'master' of git+ssh://git.freedesktop.org/git/xorg/xserver into input-hotplug

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Daniel Stone 2006-08-12 22:48:55 +03:00 committed by Daniel Stone
commit d003bada33
1 changed files with 76 additions and 17 deletions
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67
exa/exa_render.c
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@ -452,8 +452,57 @@ exaTryDriverComposite(CARD8 op,
return 1;
}
/**
* exaTryMagicTwoPassCompositeHelper implements PictOpOver using two passes of
* simpler operations PictOpOutReverse and PictOpAdd. Mainly used for component
* alpha and limited 1-tmu cards.
*
* From http://anholt.livejournal.com/32058.html:
*
* The trouble is that component-alpha rendering requires two different sources
* for blending: one for the source value to the blender, which is the
* per-channel multiplication of source and mask, and one for the source alpha
* for multiplying with the destination channels, which is the multiplication
* of the source channels by the mask alpha. So the equation for Over is:
*
* dst.A = src.A * mask.A + (1 - (src.A * mask.A)) * dst.A
* dst.R = src.R * mask.R + (1 - (src.A * mask.R)) * dst.R
* dst.G = src.G * mask.G + (1 - (src.A * mask.G)) * dst.G
* dst.B = src.B * mask.B + (1 - (src.A * mask.B)) * dst.B
*
* But we can do some simpler operations, right? How about PictOpOutReverse,
* which has a source factor of 0 and dest factor of (1 - source alpha). We
* can get the source alpha value (srca.X = src.A * mask.X) out of the texture
* blenders pretty easily. So we can do a component-alpha OutReverse, which
* gets us:
*
* dst.A = 0 + (1 - (src.A * mask.A)) * dst.A
* dst.R = 0 + (1 - (src.A * mask.R)) * dst.R
* dst.G = 0 + (1 - (src.A * mask.G)) * dst.G
* dst.B = 0 + (1 - (src.A * mask.B)) * dst.B
*
* OK. And if an op doesn't use the source alpha value for the destination
* factor, then we can do the channel multiplication in the texture blenders
* to get the source value, and ignore the source alpha that we wouldn't use.
* We've supported this in the Radeon driver for a long time. An example would
* be PictOpAdd, which does:
*
* dst.A = src.A * mask.A + dst.A
* dst.R = src.R * mask.R + dst.R
* dst.G = src.G * mask.G + dst.G
* dst.B = src.B * mask.B + dst.B
*
* Hey, this looks good! If we do a PictOpOutReverse and then a PictOpAdd right
* after it, we get:
*
* dst.A = src.A * mask.A + ((1 - (src.A * mask.A)) * dst.A)
* dst.R = src.R * mask.R + ((1 - (src.A * mask.R)) * dst.R)
* dst.G = src.G * mask.G + ((1 - (src.A * mask.G)) * dst.G)
* dst.B = src.B * mask.B + ((1 - (src.A * mask.B)) * dst.B)
*/
static int
exaTryComponentAlphaHelper(CARD8 op,
exaTryMagicTwoPassCompositeHelper(CARD8 op,
PicturePtr pSrc,
PicturePtr pMask,
PicturePtr pDst,
@ -469,7 +518,6 @@ exaTryComponentAlphaHelper(CARD8 op,
ExaScreenPriv (pDst->pDrawable->pScreen);
assert(op == PictOpOver);
assert(pMask->componentAlpha == TRUE);
if (pExaScr->info->CheckComposite &&
(!(*pExaScr->info->CheckComposite)(PictOpOutReverse, pSrc, pMask,
@ -580,17 +628,28 @@ exaComposite(CARD8 op,
(!pMask || !pMask->repeat || pMask->repeat == RepeatNormal) &&
!pSrc->alphaMap && (!pMask || !pMask->alphaMap) && !pDst->alphaMap)
{
Bool isSrcSolid;
ret = exaTryDriverComposite(op, pSrc, pMask, pDst, xSrc, ySrc, xMask,
yMask, xDst, yDst, width, height);
if (ret == 1)
goto done;
/* For generic masks and solid src pictures, mach64 can do Over in two
* passes, similar to the component-alpha case.
*/
isSrcSolid = pSrc->pDrawable->width == 1 &&
pSrc->pDrawable->height == 1 &&
pSrc->repeat;
/* If we couldn't do the Composite in a single pass, and it was a
* component-alpha Over, see if we can do it in two passes with
* an OutReverse and then an Add.
*/
if (ret == -1 && pMask && pMask->componentAlpha && op == PictOpOver) {
ret = exaTryComponentAlphaHelper(op, pSrc, pMask, pDst, xSrc, ySrc,
if (ret == -1 && op == PictOpOver && pMask &&
(pMask->componentAlpha || isSrcSolid)) {
ret = exaTryMagicTwoPassCompositeHelper(op, pSrc, pMask, pDst,
xSrc, ySrc,
xMask, yMask, xDst, yDst,
width, height);
if (ret == 1)