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 SK_DECLARE_INST_COUNT(SkGLContext) 22 23 SkGLContext(); 24 virtual ~SkGLContext(); 25 26 /** 27 * Initializes the context and makes it current. 28 */ 29 bool init(const int width, const int height); 30 getFBOID()31 int getFBOID() const { return fFBO; } 32 gl()33 const GrGLInterface* gl() const { return fGL; } 34 35 virtual void makeCurrent() const = 0; 36 37 bool hasExtension(const char* extensionName) const; 38 39 protected: 40 /** 41 * Subclass implements this to make a GL context. The returned GrGLInterface 42 * should be populated with functions compatible with the context. The 43 * format and size of backbuffers does not matter since an FBO will be 44 * created. 45 */ 46 virtual const GrGLInterface* createGLContext() = 0; 47 48 /** 49 * Subclass should destroy the underlying GL context. 50 */ 51 virtual void destroyGLContext() = 0; 52 53 private: 54 SkString fExtensionString; 55 GrGLuint fFBO; 56 GrGLuint fColorBufferID; 57 GrGLuint fDepthStencilBufferID; 58 const GrGLInterface* fGL; 59 60 typedef SkRefCnt INHERITED; 61 }; 62 63 /** 64 * Helper macro for using the GL context through the GrGLInterface. Example: 65 * SK_GL(glCtx, GenTextures(1, &texID)); 66 */ 67 #define SK_GL(ctx, X) (ctx).gl()->f ## X 68 69 #endif 70