Fix few inconsistencies in handling fixed-function texture coordinate set generation

Fix two inconsistencies in handling fixed-function texture coordinate set generation

Prevent off-by-one bug leaving the texture coordinate set 0 always enabled if
it ever was used. This makes the code consistent with its apparent purpose.

When enabling / disabling texture coordinate sets, call glPathTexGen
only if path rendering is applicable. This makes the functions
consistent with GrGpuGL::resetContext.

Committed: http://code.google.com/p/skia/source/detail?r=12074

[Kimmo Kinnunen, 2013-10-31 12:13:23]

Chris, did I understand the intention of the code correctly?
Especially wrt the second issue.
(Sorry for bundling the commits, but ..)

[bsalomon, 2013-10-31 13:08:54]

On 2013/10/31 12:13:23, kkinnunen wrote:
> Chris, did I understand the intention of the code correctly?
> Especially wrt the second issue.
> (Sorry for bundling the commits, but ..)

It lgtm if it lgt Chris.

[Chris Dalton, 2013-10-31 17:49:09]

I like what you've done here. Other than one comment, lgtm.

https://codereview.chromium.org/54403003/diff/1/src/gpu/gl/GrGLProgram.cpp
File src/gpu/gl/GrGLProgram.cpp (right):

https://codereview.chromium.org/54403003/diff/1/src/gpu/gl/GrGLProgram.cpp#ne...
src/gpu/gl/GrGLProgram.cpp:244: if (fGpu->glCaps().fixedFunctionSupport()) {
I think it would be best to leave this as 'if (!fHasVertexShader)'.

TexGen state applies to the the fixed function vertex shader, so when you have
you own shader, it's ignored. We could potentially save some work by just
leaving it if there's a vertex shader.

[Kimmo Kinnunen, 2013-11-01 06:32:10]

https://codereview.chromium.org/54403003/diff/1/src/gpu/gl/GrGLProgram.cpp
File src/gpu/gl/GrGLProgram.cpp (right):

https://codereview.chromium.org/54403003/diff/1/src/gpu/gl/GrGLProgram.cpp#ne...
src/gpu/gl/GrGLProgram.cpp:244: if (fGpu->glCaps().fixedFunctionSupport()) {
On 2013/10/31 17:49:09, Chris Dalton wrote:
> I think it would be best to leave this as 'if (!fHasVertexShader)'.
> 
> TexGen state applies to the the fixed function vertex shader, so when you have
> you own shader, it's ignored. We could potentially save some work by just
> leaving it if there's a vertex shader.

Done.

[commit-bot: I haz the power, 2013-11-01 06:32:56]

CQ is trying da patch. Follow status at
https://skia-tree-status.appspot.com/cq/kkinnunen@nvidia.com/54403003/70001

[commit-bot: I haz the power, 2013-11-01 11:54:58]

Change committed as 12074