Add isUnblended query to GrDrawState.

Add isUnblended query to GrDrawState.

BUG=skia:

Committed: https://skia.googlesource.com/skia/+/cd8b6307fe636eeff822c0e48db2a0cb80a33830

[egdaniel, 2014-11-11 20:31:48]

egdaniel@google.com changed reviewers:
+ bsalomon@google.com

[egdaniel, 2014-11-11 20:31:48]

ptal

[bsalomon, 2014-11-11 20:49:56]

https://codereview.chromium.org/715873002/diff/1/src/gpu/GrDrawState.cpp
File src/gpu/GrDrawState.cpp (right):

https://codereview.chromium.org/715873002/diff/1/src/gpu/GrDrawState.cpp#newc...
src/gpu/GrDrawState.cpp:753: bool dstCoeffIsZero = kZero_GrBlendCoeff ==
dstCoeff ||
The fact that the blend opts code doesn't directly update the coeffs is weird.
Can we make this something like

if (kISA_GrBlendCoeff == dstCoeff && srcAIsOne) {
    dstCoeff == kZero_GrBlendCoeff;
}

https://codereview.chromium.org/715873002/diff/1/src/gpu/GrDrawState.h
File src/gpu/GrDrawState.h (right):

https://codereview.chromium.org/715873002/diff/1/src/gpu/GrDrawState.h#newcod...
src/gpu/GrDrawState.h:164: * be unblended, it must have solid coverage, have
final blend coeffs [1,0], and no effect can
Can we not document the implementation but rather the meaning to the caller?
Something like "If this returns true then the render target destination pixel
values will not be read for blending during the draw."

Maybe we should call it willBlendWithDst()? (Of course that'd reverse the
boolean sense of it.)

[egdaniel, 2014-11-11 21:05:55]

https://codereview.chromium.org/715873002/diff/1/src/gpu/GrDrawState.cpp
File src/gpu/GrDrawState.cpp (right):

https://codereview.chromium.org/715873002/diff/1/src/gpu/GrDrawState.cpp#newc...
src/gpu/GrDrawState.cpp:753: bool dstCoeffIsZero = kZero_GrBlendCoeff ==
dstCoeff ||
On 2014/11/11 20:49:56, bsalomon wrote:
> The fact that the blend opts code doesn't directly update the coeffs is weird.
> Can we make this something like
> 
> if (kISA_GrBlendCoeff == dstCoeff && srcAIsOne) {
>     dstCoeff == kZero_GrBlendCoeff;
> }

Done.

https://codereview.chromium.org/715873002/diff/1/src/gpu/GrDrawState.h
File src/gpu/GrDrawState.h (right):

https://codereview.chromium.org/715873002/diff/1/src/gpu/GrDrawState.h#newcod...
src/gpu/GrDrawState.h:164: * be unblended, it must have solid coverage, have
final blend coeffs [1,0], and no effect can
On 2014/11/11 20:49:56, bsalomon wrote:
> Can we not document the implementation but rather the meaning to the caller?
> Something like "If this returns true then the render target destination pixel
> values will not be read for blending during the draw."
> 
> Maybe we should call it willBlendWithDst()? (Of course that'd reverse the
> boolean sense of it.)

Done.

[bsalomon, 2014-11-11 21:08:38]

lgtm

https://codereview.chromium.org/715873002/diff/40001/src/gpu/GrDrawState.h
File src/gpu/GrDrawState.h (right):

https://codereview.chromium.org/715873002/diff/40001/src/gpu/GrDrawState.h#ne...
src/gpu/GrDrawState.h:163: * This function returns false if the render target
destination pixel values will not be read
"true if the destination pixel values will be read" to avoid double negative?

[egdaniel, 2014-11-11 21:11:09]

The CQ bit was checked by egdaniel@google.com

[commit-bot: I haz the power, 2014-11-11 21:11:50]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/715873002/60001

[commit-bot: I haz the power, 2014-11-11 21:36:20]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-11-11 21:36:21]

Try jobs failed on following builders:
  Build-Win-VS2013-x86-Debug-Trybot on client.skia.compile
(http://build.chromium.org/p/client.skia.compile/builders/Build-Win-VS2013-x86...)

[egdaniel, 2014-11-11 22:41:43]

The CQ bit was checked by egdaniel@google.com

[commit-bot: I haz the power, 2014-11-11 22:42:42]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/715873002/60001

[commit-bot: I haz the power, 2014-11-11 22:46:11]

Committed patchset #4 (id:60001) as
https://skia.googlesource.com/skia/+/cd8b6307fe636eeff822c0e48db2a0cb80a33830