Added glResizeCHRM to resize the drawable.

Added glResizeCHRM to resize the drawable associated with the command buffer.

This new command is used to pipe resize requests to the GPU process. It will allow is to synchronize the resize with the drawing. Specifically, if we resize at the wrong time, we will damage the backbuffer, causing visual artefacts (http://code.google.com/p/chromium/issues/detail?id=54430).

The resize request gets sent to the GLContext. Each backend will implement it differently. At this point it's set as a NOP.
-I will do an XResizeWindow on Linux.
-Nat will do a resize on Windows.
-Nico (or me?) will refactor the MacOSX code to use this path.

There is one line webkit patch that's necessary to activate this code (removing an #ifdef).

BUG=none
TEST=none

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=66307

[jonathan.backer, 2010-11-10 17:09:20]

I've called the command glResizeCHRM. The CHRM indicates that this is a Chromium
GL extension. I'm open to other names.

[apatrick, 2010-11-10 18:22:31]

Remember to implement this for the OSMesa GLContexts as well. We're using them
more and more for tests. They already have the ability to resize so it shouldn't
be a lot of work.

[greggman, 2010-11-10 18:30:40]

some minor nits otherwise LGTM

http://codereview.chromium.org/4671003/diff/2001/chrome/renderer/webgraphicsc...
File chrome/renderer/webgraphicscontext3d_command_buffer_impl.cc (right):

http://codereview.chromium.org/4671003/diff/2001/chrome/renderer/webgraphicsc...
chrome/renderer/webgraphicscontext3d_command_buffer_impl.cc:230:
glResizeCHRM(width, height);
kbr would prefer we name these with CHROMIUM instead of CHRM

http://codereview.chromium.org/4671003/diff/2001/gpu/GLES2/gl2ext.h
File gpu/GLES2/gl2ext.h (right):

http://codereview.chromium.org/4671003/diff/2001/gpu/GLES2/gl2ext.h#newcode912
gpu/GLES2/gl2ext.h:912: /* GL_CHROMIUM_resize_drawable */
this comment dpesn't match

http://codereview.chromium.org/4671003/diff/2001/gpu/GLES2/gl2ext.h#newcode913
gpu/GLES2/gl2ext.h:913: #ifndef GL_CHROMIUM_resize_CHRM
the standard way for name this would be
GL_CHROMIUM_resize

no need for the CHRM on the end

[nduca, 2010-11-10 20:51:17]

General question, not necessarily for backer... is there any plumbing we need
with the extension strings? Or do we already advertise a generic Chromium
extension under which this falls?

When we merge ggl::ResizeOnscreenContext with glResizeCHROMIUM, maybe we should
we also merge in ggl::ResizeOffscreenContext?

[greggman, 2010-11-10 20:58:50]

On Wed, Nov 10, 2010 at 12:51 PM, <[email protected]> wrote:

> General question, not necessarily for backer... is there any plumbing we
> need
> with the extension strings? Or do we already advertise a generic Chromium
> extension under which this falls?
>

Yes, should probably add it to feature_info.cc around line 95 you can see
other examples.




>
> When we merge ggl::ResizeOnscreenContext with glResizeCHROMIUM, maybe we
> should
> we also merge in ggl::ResizeOffscreenContext?
>
>
> http://codereview.chromium.org/4671003/
>

[jonathan.backer, 2010-11-15 22:41:00]

http://codereview.chromium.org/4671003/diff/2001/chrome/renderer/webgraphicsc...
File chrome/renderer/webgraphicscontext3d_command_buffer_impl.cc (right):

http://codereview.chromium.org/4671003/diff/2001/chrome/renderer/webgraphicsc...
chrome/renderer/webgraphicscontext3d_command_buffer_impl.cc:230:
glResizeCHRM(width, height);
On 2010/11/10 18:30:41, greggman wrote:
> kbr would prefer we name these with CHROMIUM instead of CHRM

Done.

http://codereview.chromium.org/4671003/diff/2001/gpu/GLES2/gl2ext.h
File gpu/GLES2/gl2ext.h (right):

http://codereview.chromium.org/4671003/diff/2001/gpu/GLES2/gl2ext.h#newcode912
gpu/GLES2/gl2ext.h:912: /* GL_CHROMIUM_resize_drawable */
On 2010/11/10 18:30:41, greggman wrote:
> this comment dpesn't match

Done.

http://codereview.chromium.org/4671003/diff/2001/gpu/GLES2/gl2ext.h#newcode913
gpu/GLES2/gl2ext.h:913: #ifndef GL_CHROMIUM_resize_CHRM
On 2010/11/10 18:30:41, greggman wrote:
> the standard way for name this would be
> GL_CHROMIUM_resize
> 
> no need for the CHRM on the end

Done.

[greggman, 2010-11-15 23:33:45]

lgtm