32 bpp floating point textures

32 bpp floating point textures

This is VERY preliminary, but it was sufficient for me to get 32 bit floating point textures in a sample app

BUG=skia:

Committed: https://skia.googlesource.com/skia/+/ee5da55477d1679eaf50b56b6017cbfc07af02a7

[joshua.litt, 2014-06-27 22:58:51]

A very initial patch to add 32 bit floating point textures to GrGpuGL.  I am
sure I missed a ton of things.

This patch only adds one flavor of floating point textures, 32bpp(i.e. full
floating point textures) RGBA.  There are half float textures as well which are
still unsupported.

In the longer term, it is worth considering breaking up GrPixelConfig to add
three enums, InternalFormat, ExternalFormat, and Type.  This would allow for
more mix and match style texture creation.

[bsalomon, 2014-07-09 14:06:42]

https://codereview.chromium.org/359803003/diff/90001/src/gpu/GrRenderTarget.cpp
File src/gpu/GrRenderTarget.cpp (right):

https://codereview.chromium.org/359803003/diff/90001/src/gpu/GrRenderTarget.c...
src/gpu/GrRenderTarget.cpp:71: colorBits = GrBytesPerPixel(fDesc.fConfig) * 8;
yikes!

https://codereview.chromium.org/359803003/diff/90001/src/gpu/gl/GrGLCaps.cpp
File src/gpu/gl/GrGLCaps.cpp (right):

https://codereview.chromium.org/359803003/diff/90001/src/gpu/gl/GrGLCaps.cpp#...
src/gpu/gl/GrGLCaps.cpp:567: bool hasFPTexture = (kGL_GrGLStandard == standard);
It wasn't required in GL until 3.1 but is available before that via
GL_ARB_texture_float. We should prolly check that. We do sometimes run under old
GL versions.

https://codereview.chromium.org/359803003/diff/90001/src/gpu/gl/GrGLCaps.cpp#...
src/gpu/gl/GrGLCaps.cpp:569: hasFPTexture =
ctxInfo.hasExtension("GL_OES_texture_float");
RGBA32F is required as of ES3.1, we should check that here.

Also, if just this extension is available then only LINEAR filtering is allowed.
We'd have to make sure we never use another filtering mode. Maybe we should only
allow float textures if GL_OES_texture_float_linear is available? I'm not sure
how restrictive that is in terms of hardware.

https://codereview.chromium.org/359803003/diff/90001/tests/FloatingPointTextu...
File tests/FloatingPointTextureTest.cpp (right):

https://codereview.chromium.org/359803003/diff/90001/tests/FloatingPointTextu...
tests/FloatingPointTextureTest.cpp:62: desc.fOrigin = kGpu_TopLeft_DevType ==
gCanvasConfigs[i].fDevType ?
I think this is the only place where gCanvasConfigs is used. Maybe just have a
for (int origin = 0; origin < 2; ++origin) loop and delete the struct?

[bsalomon, 2014-07-11 16:29:59]

https://codereview.chromium.org/359803003/diff/150001/src/gpu/gl/GrGLCaps.cpp
File src/gpu/gl/GrGLCaps.cpp (right):

https://codereview.chromium.org/359803003/diff/150001/src/gpu/gl/GrGLCaps.cpp...
src/gpu/gl/GrGLCaps.cpp:574: ctxInfo.hasExtension("OES_texture_float_linear") &&
I don't think ES 3.1 has the filtering restriction (though I could be wrong).
Maybe this should be:

hasFPTexture = (kGLES_GrGLStandard == standard &&
 (version >= GR_GL_VER(3, 1) ||
(ctxInfo.hasExtension("OES_texture_float_linear") &&
ctxInfo.hasExtension("GL_OES_texture_float"));

Or since GL 3.1 also introduces this it could be:

bool hasFPTexture = version >= GR_GL_VER(3, 1);
if (!hasFPTextures)(
    hasFPTexture = ctxInfo.hasExtension("GL_ARB_texture_float") ||
(ctxInfo.hasExtension("OES_texture_float_linear") &&
ctxInfo.hasExtension("GL_OES_texture_float"));
}

[joshua.litt, 2014-07-16 16:33:41]

On 2014/07/11 16:29:59, bsalomon wrote:
> https://codereview.chromium.org/359803003/diff/150001/src/gpu/gl/GrGLCaps.cpp
> File src/gpu/gl/GrGLCaps.cpp (right):
> 
>
https://codereview.chromium.org/359803003/diff/150001/src/gpu/gl/GrGLCaps.cpp...
> src/gpu/gl/GrGLCaps.cpp:574: ctxInfo.hasExtension("OES_texture_float_linear")
&&
> I don't think ES 3.1 has the filtering restriction (though I could be wrong).
> Maybe this should be:
> 
> hasFPTexture = (kGLES_GrGLStandard == standard &&
>  (version >= GR_GL_VER(3, 1) ||
> (ctxInfo.hasExtension("OES_texture_float_linear") &&
> ctxInfo.hasExtension("GL_OES_texture_float"));
> 
> Or since GL 3.1 also introduces this it could be:
> 
> bool hasFPTexture = version >= GR_GL_VER(3, 1);
> if (!hasFPTextures)(
>     hasFPTexture = ctxInfo.hasExtension("GL_ARB_texture_float") ||
> (ctxInfo.hasExtension("OES_texture_float_linear") &&
> ctxInfo.hasExtension("GL_OES_texture_float"));
> }

Chang incorporated

[bsalomon, 2014-07-16 17:10:07]

lgtm

[joshua.litt, 2014-07-16 17:12:24]

The CQ bit was checked by joshualitt@chromium.org

[commit-bot: I haz the power, 2014-07-16 17:12:46]

CQ is trying da patch. Follow status at

https://skia-tree-status.appspot.com/cq/joshualitt@chromium.org/359803003/160001

[commit-bot: I haz the power, 2014-07-16 17:29:15]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  Build-Win7-VS2010-x86-Debug-Trybot on tryserver.skia
(http://108.170.220.76:10117/builders/Build-Win7-VS2010-x86-Debug-Trybot/build...)

[commit-bot: I haz the power, 2014-07-16 20:33:05]

Change committed as ee5da55477d1679eaf50b56b6017cbfc07af02a7