Fix case where GrGLEffectMatrix gives back a dangling ptr for the coords var name.

Fix case where GrGLEffectMatrix gives back a dangling ptr for the coords var name.

Committed: http://code.google.com/p/skia/source/detail?r=10982

[bsalomon, 2013-08-28 14:03:17]

We have this pattern of passing const char** to get return strings when building
shaders. There is an actual bug in GrGLEffectMatrix, but this is a dangerous
pattern in general and I'd like to follow this up with more signature changes
from const char** to SkString*. It may mean more allocations but shader building
should be rare and avoiding string copies seems like over-optimization when
we're about to invoke a compiler.

https://codereview.chromium.org/23706003/diff/1/src/gpu/effects/GrSimpleTextu...
File src/gpu/effects/GrSimpleTextureEffect.cpp (right):

https://codereview.chromium.org/23706003/diff/1/src/gpu/effects/GrSimpleTextu...
src/gpu/effects/GrSimpleTextureEffect.cpp:41: const char* fsVaryingNamePtr;
This is a bit ugly but I'd like to have a follow up change that makes addVarying
take a SkString* so we can just pass &fsCoordName.

[robertphillips, 2013-08-28 14:48:44]

lgtm

https://codereview.chromium.org/23706003/diff/1/src/core/SkXfermode.cpp
File src/core/SkXfermode.cpp (right):

https://codereview.chromium.org/23706003/diff/1/src/core/SkXfermode.cpp#newco...
src/core/SkXfermode.cpp:956: samplers[0],
can we not pass an SkString into appendTextureLoopup?

https://codereview.chromium.org/23706003/diff/1/src/effects/gradients/SkLinea...
File src/effects/gradients/SkLinearGradient.cpp (right):

https://codereview.chromium.org/23706003/diff/1/src/effects/gradients/SkLinea...
src/effects/gradients/SkLinearGradient.cpp:530: SkString t;
The ".c_str()" shouldn't be necessary here.

https://codereview.chromium.org/23706003/diff/1/src/effects/gradients/SkRadia...
File src/effects/gradients/SkRadialGradient.cpp (right):

https://codereview.chromium.org/23706003/diff/1/src/effects/gradients/SkRadia...
src/effects/gradients/SkRadialGradient.cpp:564: SkString t("length(");
ditto

https://codereview.chromium.org/23706003/diff/1/src/gpu/effects/GrSimpleTextu...
File src/gpu/effects/GrSimpleTextureEffect.cpp (right):

https://codereview.chromium.org/23706003/diff/1/src/gpu/effects/GrSimpleTextu...
src/gpu/effects/GrSimpleTextureEffect.cpp:41: const char* fsVaryingNamePtr;
SGTM - should vsVaryingName be changed at the same time too?

https://codereview.chromium.org/23706003/diff/1/src/gpu/effects/GrTextureDoma...
File src/gpu/effects/GrTextureDomainEffect.cpp (right):

https://codereview.chromium.org/23706003/diff/1/src/gpu/effects/GrTextureDoma...
src/gpu/effects/GrTextureDomainEffect.cpp:100: samplers[0],
can appendTextureLookupAndModulate be altered to take an SkString&?

[bsalomon, 2013-08-28 15:39:59]

https://codereview.chromium.org/23706003/diff/1/src/core/SkXfermode.cpp
File src/core/SkXfermode.cpp (right):

https://codereview.chromium.org/23706003/diff/1/src/core/SkXfermode.cpp#newco...
src/core/SkXfermode.cpp:956: samplers[0],
On 2013/08/28 14:48:44, robertphillips wrote:
> can we not pass an SkString into appendTextureLoopup?

Currently, no. We could add a helper version. I'd prefer to do that in a future
change, though.

https://codereview.chromium.org/23706003/diff/1/src/effects/gradients/SkLinea...
File src/effects/gradients/SkLinearGradient.cpp (right):

https://codereview.chromium.org/23706003/diff/1/src/effects/gradients/SkLinea...
src/effects/gradients/SkLinearGradient.cpp:530: SkString t;
On 2013/08/28 14:48:44, robertphillips wrote:
> The ".c_str()" shouldn't be necessary here.

Done.

https://codereview.chromium.org/23706003/diff/1/src/effects/gradients/SkRadia...
File src/effects/gradients/SkRadialGradient.cpp (right):

https://codereview.chromium.org/23706003/diff/1/src/effects/gradients/SkRadia...
src/effects/gradients/SkRadialGradient.cpp:564: SkString t("length(");
On 2013/08/28 14:48:44, robertphillips wrote:
> ditto

Done.

https://codereview.chromium.org/23706003/diff/1/src/gpu/effects/GrSimpleTextu...
File src/gpu/effects/GrSimpleTextureEffect.cpp (right):

https://codereview.chromium.org/23706003/diff/1/src/gpu/effects/GrSimpleTextu...
src/gpu/effects/GrSimpleTextureEffect.cpp:41: const char* fsVaryingNamePtr;
On 2013/08/28 14:48:44, robertphillips wrote:
> SGTM - should vsVaryingName be changed at the same time too?

yup

https://codereview.chromium.org/23706003/diff/1/src/gpu/effects/GrTextureDoma...
File src/gpu/effects/GrTextureDomainEffect.cpp (right):

https://codereview.chromium.org/23706003/diff/1/src/gpu/effects/GrTextureDoma...
src/gpu/effects/GrTextureDomainEffect.cpp:100: samplers[0],
On 2013/08/28 14:48:44, robertphillips wrote:
> can appendTextureLookupAndModulate be altered to take an SkString&?

I'm not sure if all callers have an SkString but we can either convert or have a
helper version. Keeping that for a follow up.

[commit-bot: I haz the power, 2013-08-28 15:40:37]

CQ is trying da patch. Follow status at
https://skia-tree-status.appspot.com/cq/bsalomon@google.com/23706003/9001

[commit-bot: I haz the power, 2013-08-28 15:59:29]

Change committed as 10982