adding glBlendEquation to GL interface

[robertphillips, 2012-04-18 12:43:35]

Brian - Apropos our conversation yesterday it looks like all the Native
interfaces (except Mac) require OpengGL >= 1.5. Since glBlendColor &
glBlendEquation were added in 1.4 we could replace all the logic in the Native
interfaces and GrGLInterface.cpp - thoughts?

[bsalomon, 2012-04-18 13:54:40]

I'm fine with requiring OpenGL 1.5+. It's low priority, though, so I wouldn't do
it unless it makes your life easier.

We can just say we require blendcolor and blendeq either by GL version or some
extension and make the validate() function just unconditionally check that they
aren't NULL. We do that with all the shader functions already. We're already
acting as if we did that with blendcolor.

http://codereview.appspot.com/6057047/diff/2001/src/gpu/gl/mac/GrGLCreateNati...
File src/gpu/gl/mac/GrGLCreateNativeInterface_mac.cpp (right):

http://codereview.appspot.com/6057047/diff/2001/src/gpu/gl/mac/GrGLCreateNati...
src/gpu/gl/mac/GrGLCreateNativeInterface_mac.cpp:65: GET_PROC(BlendColor);
I think this has to get glBlendColorExt not glBlendColor. Same below for
BlendEquation.

[robertphillips, 2012-04-18 14:24:49]

Fixed EXT issue in all Native interfaces.
Altered validate to just insist on glBlendColor & glBlendEquation.

http://codereview.appspot.com/6057047/diff/2001/src/gpu/gl/mac/GrGLCreateNati...
File src/gpu/gl/mac/GrGLCreateNativeInterface_mac.cpp (right):

http://codereview.appspot.com/6057047/diff/2001/src/gpu/gl/mac/GrGLCreateNati...
src/gpu/gl/mac/GrGLCreateNativeInterface_mac.cpp:65: GET_PROC(BlendColor);
On 2012/04/18 13:54:40, bsalomon wrote:
> I think this has to get glBlendColorExt not glBlendColor. Same below for
> BlendEquation.

Done.

[bsalomon, 2012-04-18 14:32:25]

On 2012/04/18 14:24:49, robertphillips wrote:
> Fixed EXT issue in all Native interfaces.
> Altered validate to just insist on glBlendColor & glBlendEquation.
> 
>
http://codereview.appspot.com/6057047/diff/2001/src/gpu/gl/mac/GrGLCreateNati...
> File src/gpu/gl/mac/GrGLCreateNativeInterface_mac.cpp (right):
> 
>
http://codereview.appspot.com/6057047/diff/2001/src/gpu/gl/mac/GrGLCreateNati...
> src/gpu/gl/mac/GrGLCreateNativeInterface_mac.cpp:65: GET_PROC(BlendColor);
> On 2012/04/18 13:54:40, bsalomon wrote:
> > I think this has to get glBlendColorExt not glBlendColor. Same below for
> > BlendEquation.
> 
> Done.

LGTM

[robertphillips, 2012-04-18 14:40:35]

committed as r3720