Make the Sk GL context class an abstract base class

include/gpu/gl/SkGLContext.h

 
 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
-#ifndef SkGLContextHelper_DEFINED
-#define SkGLContextHelper_DEFINED
+#ifndef SkGLContext_DEFINED
+#define SkGLContext_DEFINED
 
 #include "GrGLInterface.h"
 
 /**
  * Create an offscreen opengl context with an RGBA8 / 8bit stencil FBO.
  * Provides a GrGLInterface struct of function pointers for the context.
  */
 
-class SK_API SkGLContextHelper : public SkRefCnt {
+class SK_API SkGLContext : public SkRefCnt {
 public:
-    SK_DECLARE_INST_COUNT(SkGLContextHelper)
+    SK_DECLARE_INST_COUNT(SkGLContext)
 
-    SkGLContextHelper();
-    virtual ~SkGLContextHelper();
+    SkGLContext();
+    virtual ~SkGLContext();
 
     /**
      * Initializes the context and makes it current.
      */
     bool init(GrGLStandard forcedGpuAPI, const int width, const int height);
 
     int getFBOID() const { return fFBO; }
 
     const GrGLInterface* gl() const { return fGL; }
 
@@ skipping 40 matching lines @@
 
 private:
     GrGLuint fFBO;
     GrGLuint fColorBufferID;
     GrGLuint fDepthStencilBufferID;
     const GrGLInterface* fGL;
 
     typedef SkRefCnt INHERITED;
 };
 
+/** Creates platform-dependent GL context object
+ * Note: If Skia embedder needs a custom GL context that sets up the GL
+ * interface, this function should be implemented by the embedder.
+ * Otherwise, the default implementation for the platform should be compiled in
+ * the library.
+ */
+SK_API SkGLContext* SkCreatePlatformGLContext();
+
 /**
  * Helper macros for using the GL context through the GrGLInterface. Example:
  * SK_GL(glCtx, GenTextures(1, &texID));
  */
 #define SK_GL(ctx, X) (ctx).gl()->fFunctions.f ## X;    \
                       SkASSERT(0 == (ctx).gl()->fFunctions.fGetError())
 #define SK_GL_RET(ctx, RET, X) (RET) = (ctx).gl()->fFunctions.f ## X;    \
                   SkASSERT(0 == (ctx).gl()->fFunctions.fGetError())
 #define SK_GL_NOERRCHECK(ctx, X) (ctx).gl()->fFunctions.f ## X
 #define SK_GL_RET_NOERRCHECK(ctx, RET, X) (RET) = (ctx).gl()->fFunctions.f ## X
 
 #endif