Expose Map/UnmapTexSubImage2DCHROMIUM to pepper plugins

ppapi/c/dev/ppb_gles_chromium_extension_dev.h

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef PPAPI_C_DEV_PPB_GLES_CHROMIUM_EXTENSION_DEV_H_
+#define PPAPI_C_DEV_PPB_GLES_CHROMIUM_EXTENSION_DEV_H_
+
+#include "ppapi/c/pp_resource.h"
+#include "ppapi/c/dev/ppb_opengles_dev.h"
+
+#define PPB_GLES_CHROMIUM_EXTENSION_DEV_INTERFACE "PPB_GLESChromiumExtension(Dev);0.1"
+
+struct PPB_GLESChromiumExtension_Dev {

[apatrick, 2011/01/06 16:50:30]

There will be other CHROMIUM extensions in the future and we'll want a separate
PPAPI interface for each of them. Perhaps name this after the feature it
provides, i.e. mapping and unmapping a texture?

[piman, 2011/01/06 22:31:12]

Done. I called it ChromiumTextureMapping (under the assumption that the
extension would be called GL_CHROMIUM_texture_mapping if we had named it).

+  void* (*MapTexSubImage2DCHROMIUM)(

[brettw, 2011/01/06 17:58:24]

I don't quite get the naming convention. Why do we need CHROMIUM in all caps at
the end of each of these functions? It might also be nice to have some
documentation, even if brief (and mentioning that you should unmap it).

[piman, 2011/01/06 22:31:12]

Done. I added the doc. The naming comes from standard naming in OpenGL, where
the vendors have a suffix namespace consisting of the upper-case name, e.g. NV,
SGI, APPLE, ...
Note that I'm not making up new names, it's coming from existing code.

+     PP_Resource context,
+     GLenum target,
+     GLint level,
+     GLint xoffset,
+     GLint yoffset,
+     GLsizei width,
+     GLsizei height,
+     GLenum format,
+     GLenum type,
+     GLenum access);
+  void (*UnmapTexSubImage2DCHROMIUM)(PP_Resource context, const void* mem);
+};
+
+#endif  // PPAPI_C_DEV_PPB_GLES_CHROMIUM_EXTENSION_DEV_H_