1 files changed, 414 insertions, 0 deletions
diff --git a/include/gpu/GrGLInterface.h b/include/gpu/GrGLInterface.h
new file mode 100644
index 0000000000..8271dcbe93
--- /dev/null
+++ b/include/gpu/GrGLInterface.h
@@ -0,0 +1,414 @@
+
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+
+
+#ifndef GrGLInterface_DEFINED
+#define GrGLInterface_DEFINED
+
+#include "GrGLConfig.h"
+#include "GrRefCnt.h"
+
+#if !defined(GR_GL_FUNCTION_TYPE)
+    #define GR_GL_FUNCTION_TYPE
+#endif
+
+////////////////////////////////////////////////////////////////////////////////
+
+/**
+ * Helpers for glGetString()
+ */
+
+typedef uint32_t GrGLVersion;
+typedef uint32_t GrGLSLVersion;
+
+#define GR_GL_VER(major, minor) ((static_cast<int>(major) << 16) | \
+                                 static_cast<int>(minor))
+#define GR_GLSL_VER(major, minor) ((static_cast<int>(major) << 16) | \
+                                   static_cast<int>(minor))
+
+// these variants assume caller already has a string from glGetString()
+GrGLVersion GrGLGetVersionFromString(const char* versionString);
+GrGLSLVersion GrGLGetGLSLVersionFromString(const char* versionString);
+bool GrGLHasExtensionFromString(const char* ext, const char* extensionString);
+
+// these variants call glGetString()
+bool GrGLGetString(const GrGLInterface*, const char* ext);
+GrGLVersion GrGLGetVersion(const GrGLInterface*);
+GrGLSLVersion GrGLGetGLSLVersion(const GrGLInterface*);
+
+////////////////////////////////////////////////////////////////////////////////
+
+/**
+ * Rather than depend on platform-specific GL headers and libraries, we require
+ * the client to provide a struct of GL function pointers. This struct can be
+ * specified per-GrContext as a parameter to GrContext::Create. If NULL is
+ * passed to Create then the "default" GL interface is used. If the default is
+ * also NULL GrContext creation will fail.
+ *
+ * The default interface is returned by GrGLDefaultInterface. This function's
+ * implementation is platform-specifc. Several have been provided, along with an
+ * implementation that simply returns NULL. It is implementation-specific
+ * whether the same GrGLInterface is returned or whether a new one is created
+ * at each call. Some platforms may not be able to use a single GrGLInterface
+ * because extension function ptrs vary across contexts. Note that GrGLInterface
+ * is ref-counted. So if the same object is returned by multiple calls to 
+ * GrGLDefaultInterface, each should bump the ref count.
+ *
+ * By defining GR_GL_PER_GL_CALL_IFACE_CALLBACK to 1 the client can specify a
+ * callback function that will be called prior to each GL function call. See
+ * comments in GrGLConfig.h
+ */
+
+struct GrGLInterface;
+
+const GrGLInterface* GrGLDefaultInterface();
+
+typedef unsigned int GrGLenum;
+typedef unsigned char GrGLboolean;
+typedef unsigned int GrGLbitfield;
+typedef signed char GrGLbyte;
+typedef char GrGLchar;
+typedef short GrGLshort;
+typedef int GrGLint;
+typedef int GrGLsizei;
+typedef unsigned char GrGLubyte;
+typedef unsigned short GrGLushort;
+typedef unsigned int GrGLuint;
+typedef float GrGLfloat;
+typedef float GrGLclampf;
+typedef double GrGLdouble;
+typedef double GrGLclampd;
+typedef void GrGLvoid;
+typedef long GrGLintptr;
+typedef long GrGLsizeiptr;
+
+enum GrGLBinding {
+    kDesktop_GrGLBinding = 0x01,
+    kES1_GrGLBinding = 0x02,
+    kES2_GrGLBinding = 0x04
+};
+
+extern "C" {
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLActiveTextureProc)(GrGLenum texture);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLAttachShaderProc)(GrGLuint program, GrGLuint shader);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLBindAttribLocationProc)(GrGLuint program, GrGLuint index, const char* name);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLBindBufferProc)(GrGLenum target, GrGLuint buffer);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLBindTextureProc)(GrGLenum target, GrGLuint texture);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLBlendColorProc)(GrGLclampf red, GrGLclampf green, GrGLclampf blue, GrGLclampf alpha);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLBindFragDataLocationProc)(GrGLuint program, GrGLuint colorNumber, const GrGLchar* name);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLBlendFuncProc)(GrGLenum sfactor, GrGLenum dfactor);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLBufferDataProc)(GrGLenum target, GrGLsizeiptr size, const GrGLvoid* data, GrGLenum usage);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLBufferSubDataProc)(GrGLenum target, GrGLintptr offset, GrGLsizeiptr size, const GrGLvoid* data);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLClearProc)(GrGLbitfield mask);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLClearColorProc)(GrGLclampf red, GrGLclampf green, GrGLclampf blue, GrGLclampf alpha);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLClearStencilProc)(GrGLint s);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLClientActiveTextureProc)(GrGLenum texture);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLColor4ubProc)(GrGLubyte red, GrGLubyte green, GrGLubyte blue, GrGLubyte alpha);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLColorMaskProc)(GrGLboolean red, GrGLboolean green, GrGLboolean blue, GrGLboolean alpha);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLColorPointerProc)(GrGLint size, GrGLenum type, GrGLsizei stride, const GrGLvoid* pointer);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLCompileShaderProc)(GrGLuint shader);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLCompressedTexImage2DProc)(GrGLenum target, GrGLint level, GrGLenum internalformat, GrGLsizei width, GrGLsizei height, GrGLint border, GrGLsizei imageSize, const GrGLvoid* data);
+    typedef GrGLuint (GR_GL_FUNCTION_TYPE *GrGLCreateProgramProc)(void);
+    typedef GrGLuint (GR_GL_FUNCTION_TYPE *GrGLCreateShaderProc)(GrGLenum type);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLCullFaceProc)(GrGLenum mode);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLDeleteBuffersProc)(GrGLsizei n, const GrGLuint* buffers);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLDeleteProgramProc)(GrGLuint program);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLDeleteShaderProc)(GrGLuint shader);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLDeleteTexturesProc)(GrGLsizei n, const GrGLuint* textures);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLDepthMaskProc)(GrGLboolean flag);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLDisableProc)(GrGLenum cap);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLDisableClientStateProc)(GrGLenum array);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLDisableVertexAttribArrayProc)(GrGLuint index);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLDrawArraysProc)(GrGLenum mode, GrGLint first, GrGLsizei count);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLDrawBufferProc)(GrGLenum mode);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLDrawBuffersProc)(GrGLsizei n, const GrGLenum* bufs);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLDrawElementsProc)(GrGLenum mode, GrGLsizei count, GrGLenum type, const GrGLvoid* indices);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLEnableProc)(GrGLenum cap);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLEnableClientStateProc)(GrGLenum cap);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLEnableVertexAttribArrayProc)(GrGLuint index);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLFrontFaceProc)(GrGLenum mode);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLGenBuffersProc)(GrGLsizei n, GrGLuint* buffers);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLGenTexturesProc)(GrGLsizei n, GrGLuint* textures);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLGetBufferParameterivProc)(GrGLenum target, GrGLenum pname, GrGLint* params);
+    typedef GrGLenum (GR_GL_FUNCTION_TYPE *GrGLGetErrorProc)(void);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLGetIntegervProc)(GrGLenum pname, GrGLint* params);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLGetProgramInfoLogProc)(GrGLuint program, GrGLsizei bufsize, GrGLsizei* length, char* infolog);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLGetProgramivProc)(GrGLuint program, GrGLenum pname, GrGLint* params);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLGetShaderInfoLogProc)(GrGLuint shader, GrGLsizei bufsize, GrGLsizei* length, char* infolog);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLGetShaderivProc)(GrGLuint shader, GrGLenum pname, GrGLint* params);
+    typedef const GrGLubyte* (GR_GL_FUNCTION_TYPE *GrGLGetStringProc)(GrGLenum name);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLGetTexLevelParameteriv)(GrGLenum target, GrGLint level, GrGLenum pname, GrGLint* params);
+    typedef GrGLint (GR_GL_FUNCTION_TYPE *GrGLGetUniformLocationProc)(GrGLuint program, const char* name);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLLineWidthProc)(GrGLfloat width);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLLinkProgramProc)(GrGLuint program);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLLoadMatrixfProc)(const GrGLfloat* m);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLMatrixModeProc)(GrGLenum mode);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLPixelStoreiProc)(GrGLenum pname, GrGLint param);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLPointSizeProc)(GrGLfloat size);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLReadBufferProc)(GrGLenum src);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLReadPixelsProc)(GrGLint x, GrGLint y, GrGLsizei width, GrGLsizei height, GrGLenum format, GrGLenum type, GrGLvoid* pixels);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLScissorProc)(GrGLint x, GrGLint y, GrGLsizei width, GrGLsizei height);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLShadeModelProc)(GrGLenum mode);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLShaderSourceProc)(GrGLuint shader, GrGLsizei count, const char** str, const GrGLint* length);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLStencilFuncProc)(GrGLenum func, GrGLint ref, GrGLuint mask);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLStencilFuncSeparateProc)(GrGLenum face, GrGLenum func, GrGLint ref, GrGLuint mask);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLStencilMaskProc)(GrGLuint mask);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLStencilMaskSeparateProc)(GrGLenum face, GrGLuint mask);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLStencilOpProc)(GrGLenum fail, GrGLenum zfail, GrGLenum zpass);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLStencilOpSeparateProc)(GrGLenum face, GrGLenum fail, GrGLenum zfail, GrGLenum zpass);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLTexCoordPointerProc)(GrGLint size, GrGLenum type, GrGLsizei stride, const GrGLvoid* pointer);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLTexEnviProc)(GrGLenum target, GrGLenum pname, GrGLint param);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLTexImage2DProc)(GrGLenum target, GrGLint level, GrGLint internalformat, GrGLsizei width, GrGLsizei height, GrGLint border, GrGLenum format, GrGLenum type, const GrGLvoid* pixels);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLTexParameteriProc)(GrGLenum target, GrGLenum pname, GrGLint param);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLTexSubImage2DProc)(GrGLenum target, GrGLint level, GrGLint xoffset, GrGLint yoffset, GrGLsizei width, GrGLsizei height, GrGLenum format, GrGLenum type, const GrGLvoid* pixels);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniform1fProc)(GrGLint location, GrGLfloat v0);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniform1iProc)(GrGLint location, GrGLint v0);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniform1fvProc)(GrGLint location, GrGLsizei count, const GrGLfloat* v);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniform1ivProc)(GrGLint location, GrGLsizei count, const GrGLint* v);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniform2fProc)(GrGLint location, GrGLfloat v0, GrGLfloat v1);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniform2iProc)(GrGLint location, GrGLint v0, GrGLint v1);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniform2fvProc)(GrGLint location, GrGLsizei count, const GrGLfloat* v);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniform2ivProc)(GrGLint location, GrGLsizei count, const GrGLint* v);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniform3fProc)(GrGLint location, GrGLfloat v0, GrGLfloat v1, GrGLfloat v2);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniform3iProc)(GrGLint location, GrGLint v0, GrGLint v1, GrGLint v2);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniform3fvProc)(GrGLint location, GrGLsizei count, const GrGLfloat* v);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniform3ivProc)(GrGLint location, GrGLsizei count, const GrGLint* v);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniform4fProc)(GrGLint location, GrGLfloat v0, GrGLfloat v1, GrGLfloat v2, GrGLfloat v3);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniform4iProc)(GrGLint location, GrGLint v0, GrGLint v1, GrGLint v2, GrGLint v3);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniform4fvProc)(GrGLint location, GrGLsizei count, const GrGLfloat* v);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniform4ivProc)(GrGLint location, GrGLsizei count, const GrGLint* v);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniformMatrix2fvProc)(GrGLint location, GrGLsizei count, GrGLboolean transpose, const GrGLfloat* value);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniformMatrix3fvProc)(GrGLint location, GrGLsizei count, GrGLboolean transpose, const GrGLfloat* value);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUniformMatrix4fvProc)(GrGLint location, GrGLsizei count, GrGLboolean transpose, const GrGLfloat* value);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLUseProgramProc)(GrGLuint program);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLVertexAttrib4fvProc)(GrGLuint indx, const GrGLfloat* values);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLVertexAttribPointerProc)(GrGLuint indx, GrGLint size, GrGLenum type, GrGLboolean normalized, GrGLsizei stride, const GrGLvoid* ptr);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLVertexPointerProc)(GrGLint size, GrGLenum type, GrGLsizei stride, const GrGLvoid* pointer);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLViewportProc)(GrGLint x, GrGLint y, GrGLsizei width, GrGLsizei height);
+
+    // FBO Extension Functions
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLBindFramebufferProc)(GrGLenum target, GrGLuint framebuffer);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLBindRenderbufferProc)(GrGLenum target, GrGLuint renderbuffer);
+    typedef GrGLenum (GR_GL_FUNCTION_TYPE *GrGLCheckFramebufferStatusProc)(GrGLenum target);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLDeleteFramebuffersProc)(GrGLsizei n, const GrGLuint *framebuffers);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLDeleteRenderbuffersProc)(GrGLsizei n, const GrGLuint *renderbuffers);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLFramebufferRenderbufferProc)(GrGLenum target, GrGLenum attachment, GrGLenum renderbuffertarget, GrGLuint renderbuffer);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLFramebufferTexture2DProc)(GrGLenum target, GrGLenum attachment, GrGLenum textarget, GrGLuint texture, GrGLint level);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLGenFramebuffersProc)(GrGLsizei n, GrGLuint *framebuffers);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLGenRenderbuffersProc)(GrGLsizei n, GrGLuint *renderbuffers);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLGetFramebufferAttachmentParameterivProc)(GrGLenum target, GrGLenum attachment, GrGLenum pname, GrGLint* params);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLGetRenderbufferParameterivProc)(GrGLenum target, GrGLenum pname, GrGLint* params);
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLRenderbufferStorageProc)(GrGLenum target, GrGLenum internalformat, GrGLsizei width, GrGLsizei height);
+
+    // Multisampling Extension Functions
+    // same prototype for ARB_FBO, EXT_FBO, GL 3.0, & Apple ES extension
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLRenderbufferStorageMultisampleProc)(GrGLenum target, GrGLsizei samples, GrGLenum internalformat, GrGLsizei width, GrGLsizei height);
+    // desktop: ext_fbo_blit, arb_fbo, gl 3.0
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLBlitFramebufferProc)(GrGLint srcX0, GrGLint srcY0, GrGLint srcX1, GrGLint srcY1, GrGLint dstX0, GrGLint dstY0, GrGLint dstX1, GrGLint dstY1, GrGLbitfield mask, GrGLenum filter);
+    // apple's es extension
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLResolveMultisampleFramebufferProc)();
+
+    // Buffer mapping (extension in ES).
+    typedef GrGLvoid* (GR_GL_FUNCTION_TYPE *GrGLMapBufferProc)(GrGLenum target, GrGLenum access);
+    typedef GrGLboolean (GR_GL_FUNCTION_TYPE *GrGLUnmapBufferProc)(GrGLenum target);
+
+    // Dual source blending
+    typedef GrGLvoid (GR_GL_FUNCTION_TYPE *GrGLBindFragDataLocationIndexedProc)(GrGLuint program, GrGLuint colorNumber, GrGLuint index, const GrGLchar * name);
+}  // extern "C"
+
+#if GR_GL_PER_GL_FUNC_CALLBACK
+typedef void (*GrGLInterfaceCallbackProc)(const GrGLInterface*);
+typedef intptr_t GrGLInterfaceCallbackData;
+#endif
+
+
+enum GrGLCapability {
+    kProbe_GrGLCapability = -1
+};
+
+/*
+ * The following interface exports the OpenGL entry points used by the system.
+ * Use of OpenGL calls is disallowed.  All calls should be invoked through
+ * the global instance of this struct, defined above.
+ *
+ * IMPORTANT NOTE: The OpenGL entry points exposed here include both core GL
+ * functions, and extensions.  The system assumes that the address of the
+ * extension pointer will be valid across contexts.
+ */
+struct GR_API GrGLInterface : public GrRefCnt {
+
+    GrGLInterface();
+
+    bool validate(GrEngine engine) const;
+    bool supportsDesktop() const {
+        return 0 != (kDesktop_GrGLBinding & fBindingsExported);
+    }
+    bool supportsES1() const {
+        return 0 != (kES1_GrGLBinding & fBindingsExported);
+    }
+    bool supportsES2() const {
+        return 0 !=  (kES2_GrGLBinding & fBindingsExported);
+    }
+    bool supportsES() const {
+        return 0 != ((kES1_GrGLBinding | kES2_GrGLBinding) &
+                        fBindingsExported);
+    }
+
+    // Indicator variable specifying the type of GL implementation
+    // exported:  GLES{1|2} or Desktop.
+    GrGLBinding fBindingsExported;
+
+    /// Does this GL support NPOT textures on FBOs?
+    /// boolean value, or kProbe_GrGLCapability to probe (slowly) at context creation.
+    int fNPOTRenderTargetSupport;
+
+    /// Some GL implementations (PowerVR SGX devices like the iPhone 4)
+    /// have restrictions on the size of small render targets.
+    /// kProbe_GrGLCapability to probe (slowly) at context creation.
+    int fMinRenderTargetHeight;
+    int fMinRenderTargetWidth;
+
+    GrGLActiveTextureProc fActiveTexture;
+    GrGLAttachShaderProc fAttachShader;
+    GrGLBindAttribLocationProc fBindAttribLocation;
+    GrGLBindBufferProc fBindBuffer;
+    GrGLBindFragDataLocationProc fBindFragDataLocation;
+    GrGLBindTextureProc fBindTexture;
+    GrGLBlendColorProc fBlendColor;
+    GrGLBlendFuncProc fBlendFunc;
+    GrGLBufferDataProc fBufferData;
+    GrGLBufferSubDataProc fBufferSubData;
+    GrGLClearProc fClear;
+    GrGLClearColorProc fClearColor;
+    GrGLClearStencilProc fClearStencil;
+    GrGLClientActiveTextureProc fClientActiveTexture;
+    GrGLColor4ubProc fColor4ub;
+    GrGLColorMaskProc fColorMask;
+    GrGLColorPointerProc fColorPointer;
+    GrGLCompileShaderProc fCompileShader;
+    GrGLCompressedTexImage2DProc fCompressedTexImage2D;
+    GrGLCreateProgramProc fCreateProgram;
+    GrGLCreateShaderProc fCreateShader;
+    GrGLCullFaceProc fCullFace;
+    GrGLDeleteBuffersProc fDeleteBuffers;
+    GrGLDeleteProgramProc fDeleteProgram;
+    GrGLDeleteShaderProc fDeleteShader;
+    GrGLDeleteTexturesProc fDeleteTextures;
+    GrGLDepthMaskProc fDepthMask;
+    GrGLDisableProc fDisable;
+    GrGLDisableClientStateProc fDisableClientState;
+    GrGLDisableVertexAttribArrayProc fDisableVertexAttribArray;
+    GrGLDrawArraysProc fDrawArrays;
+    GrGLDrawBufferProc fDrawBuffer;
+    GrGLDrawBuffersProc fDrawBuffers;
+    GrGLDrawElementsProc fDrawElements;
+    GrGLEnableProc fEnable;
+    GrGLEnableClientStateProc fEnableClientState;
+    GrGLEnableVertexAttribArrayProc fEnableVertexAttribArray;
+    GrGLFrontFaceProc fFrontFace;
+    GrGLGenBuffersProc fGenBuffers;
+    GrGLGenTexturesProc fGenTextures;
+    GrGLGetBufferParameterivProc fGetBufferParameteriv;
+    GrGLGetErrorProc fGetError;
+    GrGLGetIntegervProc fGetIntegerv;
+    GrGLGetProgramInfoLogProc fGetProgramInfoLog;
+    GrGLGetProgramivProc fGetProgramiv;
+    GrGLGetShaderInfoLogProc fGetShaderInfoLog;
+    GrGLGetShaderivProc fGetShaderiv;
+    GrGLGetStringProc fGetString;
+    GrGLGetTexLevelParameteriv fGetTexLevelParameteriv;
+    GrGLGetUniformLocationProc fGetUniformLocation;
+    GrGLLineWidthProc fLineWidth;
+    GrGLLinkProgramProc fLinkProgram;
+    GrGLLoadMatrixfProc fLoadMatrixf;
+    GrGLMatrixModeProc fMatrixMode;
+    GrGLPixelStoreiProc fPixelStorei;
+    GrGLPointSizeProc fPointSize;
+    GrGLReadBufferProc fReadBuffer;
+    GrGLReadPixelsProc fReadPixels;
+    GrGLScissorProc fScissor;
+    GrGLShadeModelProc fShadeModel;
+    GrGLShaderSourceProc fShaderSource;
+    GrGLStencilFuncProc fStencilFunc;
+    GrGLStencilFuncSeparateProc fStencilFuncSeparate;
+    GrGLStencilMaskProc fStencilMask;
+    GrGLStencilMaskSeparateProc fStencilMaskSeparate;
+    GrGLStencilOpProc fStencilOp;
+    GrGLStencilOpSeparateProc fStencilOpSeparate;
+    GrGLTexCoordPointerProc fTexCoordPointer;
+    GrGLTexEnviProc fTexEnvi;
+    GrGLTexImage2DProc fTexImage2D;
+    GrGLTexParameteriProc fTexParameteri;
+    GrGLTexSubImage2DProc fTexSubImage2D;
+    GrGLUniform1fProc fUniform1f;
+    GrGLUniform1iProc fUniform1i;
+    GrGLUniform1fvProc fUniform1fv;
+    GrGLUniform1ivProc fUniform1iv;
+    GrGLUniform2fProc fUniform2f;
+    GrGLUniform2iProc fUniform2i;
+    GrGLUniform2fvProc  fUniform2fv;
+    GrGLUniform2ivProc fUniform2iv;
+    GrGLUniform3fProc fUniform3f;
+    GrGLUniform3iProc fUniform3i;
+    GrGLUniform3fvProc fUniform3fv;
+    GrGLUniform3ivProc fUniform3iv;
+    GrGLUniform4fProc fUniform4f;
+    GrGLUniform4iProc fUniform4i;
+    GrGLUniform4fvProc fUniform4fv;
+    GrGLUniform4ivProc fUniform4iv;
+    GrGLUniformMatrix2fvProc fUniformMatrix2fv;
+    GrGLUniformMatrix3fvProc fUniformMatrix3fv;
+    GrGLUniformMatrix4fvProc fUniformMatrix4fv;
+    GrGLUseProgramProc fUseProgram;
+    GrGLVertexAttrib4fvProc fVertexAttrib4fv;
+    GrGLVertexAttribPointerProc fVertexAttribPointer;
+    GrGLVertexPointerProc fVertexPointer;
+    GrGLViewportProc fViewport;
+
+    // FBO Extension Functions
+    GrGLBindFramebufferProc fBindFramebuffer;
+    GrGLBindRenderbufferProc fBindRenderbuffer;
+    GrGLCheckFramebufferStatusProc fCheckFramebufferStatus;
+    GrGLDeleteFramebuffersProc fDeleteFramebuffers;
+    GrGLDeleteRenderbuffersProc fDeleteRenderbuffers;
+    GrGLFramebufferRenderbufferProc fFramebufferRenderbuffer;
+    GrGLFramebufferTexture2DProc fFramebufferTexture2D;
+    GrGLGenFramebuffersProc fGenFramebuffers;
+    GrGLGenRenderbuffersProc fGenRenderbuffers;
+    GrGLGetFramebufferAttachmentParameterivProc fGetFramebufferAttachmentParameteriv;
+    GrGLGetRenderbufferParameterivProc fGetRenderbufferParameteriv;
+    GrGLRenderbufferStorageProc fRenderbufferStorage;
+
+    // Multisampling Extension Functions
+    // same prototype for ARB_FBO, EXT_FBO, GL 3.0, & Apple ES extension
+    GrGLRenderbufferStorageMultisampleProc fRenderbufferStorageMultisample;
+    // desktop: ext_fbo_blit, arb_fbo, gl 3.0
+    GrGLBlitFramebufferProc fBlitFramebuffer;
+    // apple's es extension
+    GrGLResolveMultisampleFramebufferProc fResolveMultisampleFramebuffer;
+
+    // Buffer mapping (extension in ES).
+    GrGLMapBufferProc fMapBuffer;
+    GrGLUnmapBufferProc fUnmapBuffer;
+
+    // Dual Source Blending
+    GrGLBindFragDataLocationIndexedProc fBindFragDataLocationIndexed;
+
+    // Per-GL func callback
+#if GR_GL_PER_GL_FUNC_CALLBACK
+    GrGLInterfaceCallbackProc fCallback;
+    GrGLInterfaceCallbackData fCallbackData;
+#endif
+
+private:
+    bool validateShaderFunctions() const;
+    bool validateFixedFunctions() const;
+};
+
+#endif