Adds support for the GL_ANGLE_texture_usage and GL_EXT_texture_storage

gpu/command_buffer/build_gles2_cmd_buffer.py

Index: gpu/command_buffer/build_gles2_cmd_buffer.py
===================================================================
--- gpu/command_buffer/build_gles2_cmd_buffer.py	(revision 112643)
+++ gpu/command_buffer/build_gles2_cmd_buffer.py	(working copy)
@@ -201,6 +201,7 @@
 GL_APICALL void         GL_APIENTRY glViewport (GLint x, GLint y, GLsizei width, GLsizei height);
 GL_APICALL void         GL_APIENTRY glBlitFramebufferEXT (GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1, GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1, GLbitfield mask, GLenumBlitFilter filter);
 GL_APICALL void         GL_APIENTRY glRenderbufferStorageMultisampleEXT (GLenumRenderBufferTarget target, GLsizei samples, GLenumRenderBufferFormat internalformat, GLsizei width, GLsizei height);
+GL_APICALL void         GL_APIENTRY glTexStorage2DEXT (GLenumTextureTarget target, GLsizei levels, GLintTextureInternalFormatStorage internalFormat, GLsizei width, GLsizei height);
 // Non-GL commands.
 GL_APICALL void         GL_APIENTRY glSwapBuffers (void);
 GL_APICALL GLuint       GL_APIENTRY glGetMaxValueInBufferCHROMIUM (GLidBuffer buffer_id, GLsizei count, GLenumGetMaxIndexType type, GLuint offset);
@@ -436,6 +437,7 @@
   'GetTranslatedShaderSourceANGLE':                            456,
   'PostSubBufferCHROMIUM':                                     457,
   'TexImageIOSurface2DCHROMIUM':                               458,
+  'TexStorage2DEXT':                                           459,
 }
 
 # This is a list of enum names and their valid values. It is used to map
@@ -898,6 +900,13 @@
       'GL_LINEAR',
     ],
   },
+  'TextureUsage': {
+    'type': 'GLenum',
+    'valid': [
+      'GL_NONE',
+      'GL_FRAMEBUFFER_ATTACHMENT_ANGLE',
+    ],
+  },
   'VertexAttribute': {
     'type': 'GLenum',
     'valid': [
@@ -1036,6 +1045,19 @@
       'GL_BGR',
     ],
   },
+  'TextureInternalFormatStorage': {
+    'type': 'GLenum',
+    'valid': [
+      'GL_RGB565',
+      'GL_RGBA4',
+      'GL_RGB5_A1',
+      'GL_ALPHA8_EXT',
+      'GL_LUMINANCE8_EXT',
+      'GL_LUMINANCE8_ALPHA8_EXT',
+      'GL_RGB8_OES',
+      'GL_RGBA8_OES',

[greggman, 2011/12/02 18:33:24]

these formats probably need to be added to
src/gpu/command_buffer/common/gles2_cmd_utils.cc 
in ElementsPerGroup and GetChannelsForFormat

[vangelis, 2011/12/03 00:19:53]

These enums are only valid when supplying them to glTexStorage2D. They combine
the format and type parameter into one.  The actual internalformat of the
texture allocated is still one of the traditional GL formats. For example, using
GL_RGB565 when allocating with glTexStorage2D will result in a texture with
format = GL_RGB and type = GL_UNSIGNED_SHORT_5_6_6.

It looks like ElementsPerGroup and GetChannelsForFormat only get called with
valid texture formats. 

Am I reading this wrong?

[greggman, 2011/12/03 01:41:01]

I see. Hmm, well, I guess it's fine. That seems to go against OpenGL ES 2.0 in
that there are no conversions and the formats have to be the same. I feel like
you should pass in type/format to TexStorage so you can know to use the same
type/format in TexSubImage2D but okay I guess.

+    ],
+  },
   'VertexAttribType': {
     'type': 'GLenum',
     'valid': [
@@ -1801,6 +1823,12 @@
     'extension': True,
     'chromium': True,
   },
+  'TexStorage2DEXT': {
+    'unit_test': False,
+    'extension': True,
+    'decoder_func': 'DoTexStorage2DEXT',
+  },
+
 }