1 2 /* 3 * Copyright 2011 Google Inc. 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 #ifndef SkGLContext_DEFINED 9 #define SkGLContext_DEFINED 10 11 #include "GrGLInterface.h" 12 #include "SkString.h" 13 14 /** 15 * Create an offscreen opengl context with an RGBA8 / 8bit stencil FBO. 16 * Provides a GrGLInterface struct of function pointers for the context. 17 */ 18 19 class SkGLContext : public SkRefCnt { 20 public: 21 SkGLContext(); 22 virtual ~SkGLContext(); 23 24 /** 25 * Initializes the context and makes it current. 26 */ 27 bool init(const int width, const int height); 28 getFBOID()29 int getFBOID() const { return fFBO; } 30 gl()31 const GrGLInterface* gl() const { return fGL; } 32 33 virtual void makeCurrent() const = 0; 34 35 bool hasExtension(const char* extensionName) const; 36 37 protected: 38 /** 39 * Subclass implements this to make a GL context. The returned GrGLInterface 40 * should be populated with functions compatible with the context. The 41 * format and size of backbuffers does not matter since an FBO will be 42 * created. 43 */ 44 virtual const GrGLInterface* createGLContext() = 0; 45 46 /** 47 * Subclass should destroy the underlying GL context. 48 */ 49 virtual void destroyGLContext() = 0; 50 51 private: 52 SkString fExtensionString; 53 GrGLuint fFBO; 54 const GrGLInterface* fGL; 55 }; 56 57 /** 58 * Helper macro for using the GL context through the GrGLInterface. Example: 59 * SK_GL(glCtx, GenTextures(1, &texID)); 60 */ 61 #define SK_GL(ctx, X) (ctx).gl()->f ## X 62 63 #endif 64