1 /* 2 * Copyright 2011 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 #ifndef SkWGL_DEFINED 8 #define SkWGL_DEFINED 9 10 #include "include/core/SkRefCnt.h" 11 #include "src/base/SkLeanWindows.h" 12 13 /** 14 * Working with WGL extensions can be a pain. Among the reasons is that you must 15 * have a GL context to get the proc addresses, but you want to use the procs to 16 * create a context in the first place. So you have to create a placeholder GL 17 * ctx to get the proc addresses. 18 * 19 * This file helps by providing SkCreateWGLInterface(). It returns a struct of 20 * function pointers that it initializes. It also has a helper function to query 21 * for WGL extensions. It handles the fact that wglGetExtensionsString is itself 22 * an extension. 23 */ 24 25 #define SK_WGL_DRAW_TO_WINDOW 0x2001 26 #define SK_WGL_ACCELERATION 0x2003 27 #define SK_WGL_SUPPORT_OPENGL 0x2010 28 #define SK_WGL_DOUBLE_BUFFER 0x2011 29 #define SK_WGL_COLOR_BITS 0x2014 30 #define SK_WGL_RED_BITS 0x2015 31 #define SK_WGL_GREEN_BITS 0x2017 32 #define SK_WGL_BLUE_BITS 0x2019 33 #define SK_WGL_ALPHA_BITS 0x201B 34 #define SK_WGL_STENCIL_BITS 0x2023 35 #define SK_WGL_FULL_ACCELERATION 0x2027 36 #define SK_WGL_SAMPLE_BUFFERS 0x2041 37 #define SK_WGL_SAMPLES 0x2042 38 #define SK_WGL_CONTEXT_MAJOR_VERSION 0x2091 39 #define SK_WGL_CONTEXT_MINOR_VERSION 0x2092 40 #define SK_WGL_CONTEXT_LAYER_PLANE 0x2093 41 #define SK_WGL_CONTEXT_FLAGS 0x2094 42 #define SK_WGL_CONTEXT_PROFILE_MASK 0x9126 43 #define SK_WGL_CONTEXT_DEBUG_BIT 0x0001 44 #define SK_WGL_CONTEXT_FORWARD_COMPATIBLE_BIT 0x0002 45 #define SK_WGL_CONTEXT_CORE_PROFILE_BIT 0x00000001 46 #define SK_WGL_CONTEXT_COMPATIBILITY_PROFILE_BIT 0x00000002 47 #define SK_WGL_CONTEXT_ES2_PROFILE_BIT 0x00000004 48 #define SK_ERROR_INVALID_VERSION 0x2095 49 #define SK_ERROR_INVALID_PROFILE 0x2096 50 51 DECLARE_HANDLE(HPBUFFER); 52 53 class SkWGLExtensions { 54 public: 55 SkWGLExtensions(); 56 /** 57 * Determines if an extensions is available for a given DC. 58 * WGL_extensions_string is considered a prerequisite for all other 59 * extensions. It is necessary to check this before calling other class 60 * functions. 61 */ 62 bool hasExtension(HDC dc, const char* ext) const; 63 64 const char* getExtensionsString(HDC hdc) const; 65 BOOL choosePixelFormat(HDC hdc, const int*, const FLOAT*, UINT, int*, UINT*) const; 66 BOOL getPixelFormatAttribiv(HDC, int, int, UINT, const int*, int*) const; 67 BOOL getPixelFormatAttribfv(HDC hdc, int, int, UINT, const int*, FLOAT*) const; 68 HGLRC createContextAttribs(HDC, HGLRC, const int *) const; 69 70 BOOL swapInterval(int interval) const; 71 72 HPBUFFER createPbuffer(HDC, int , int, int, const int*) const; 73 HDC getPbufferDC(HPBUFFER) const; 74 int releasePbufferDC(HPBUFFER, HDC) const; 75 BOOL destroyPbuffer(HPBUFFER) const; 76 77 /** 78 * WGL doesn't have precise rules for the ordering of formats returned 79 * by wglChoosePixelFormat. This function helps choose among the set of 80 * formats returned by wglChoosePixelFormat. The rules in decreasing 81 * priority are: 82 * * Choose formats with the smallest sample count that is >= 83 * desiredSampleCount (or the largest sample count if all formats have 84 * fewer samples than desiredSampleCount.) If desiredSampleCount is 1 then 85 * all msaa formats are excluded from consideration. 86 * * Choose formats with the fewest color samples when coverage sampling 87 * is available. 88 * * If the above rules leave multiple formats, choose the one that 89 * appears first in the formats array parameter. 90 */ 91 int selectFormat(const int formats[], 92 int formatCount, 93 HDC dc, 94 int desiredSampleCount) const; 95 private: 96 typedef const char* (WINAPI *GetExtensionsStringProc)(HDC); 97 typedef BOOL (WINAPI *ChoosePixelFormatProc)(HDC, const int *, const FLOAT *, UINT, int *, UINT *); 98 typedef BOOL (WINAPI *GetPixelFormatAttribivProc)(HDC, int, int, UINT, const int*, int*); 99 typedef BOOL (WINAPI *GetPixelFormatAttribfvProc)(HDC, int, int, UINT, const int*, FLOAT*); 100 typedef HGLRC (WINAPI *CreateContextAttribsProc)(HDC, HGLRC, const int *); 101 typedef BOOL (WINAPI* SwapIntervalProc)(int); 102 typedef HPBUFFER (WINAPI* CreatePbufferProc)(HDC, int , int, int, const int*); 103 typedef HDC (WINAPI* GetPbufferDCProc)(HPBUFFER); 104 typedef int (WINAPI* ReleasePbufferDCProc)(HPBUFFER, HDC); 105 typedef BOOL (WINAPI* DestroyPbufferProc)(HPBUFFER); 106 107 static GetExtensionsStringProc fGetExtensionsString; 108 static ChoosePixelFormatProc fChoosePixelFormat; 109 static GetPixelFormatAttribfvProc fGetPixelFormatAttribfv; 110 static GetPixelFormatAttribivProc fGetPixelFormatAttribiv; 111 static CreateContextAttribsProc fCreateContextAttribs; 112 static SwapIntervalProc fSwapInterval; 113 static CreatePbufferProc fCreatePbuffer; 114 static GetPbufferDCProc fGetPbufferDC; 115 static ReleasePbufferDCProc fReleasePbufferDC; 116 static DestroyPbufferProc fDestroyPbuffer; 117 }; 118 119 enum SkWGLContextRequest { 120 /** Requests to create core profile context if possible, otherwise 121 compatibility profile. */ 122 kGLPreferCoreProfile_SkWGLContextRequest, 123 /** Requests to create compatibility profile context if possible, otherwise 124 core profile. */ 125 kGLPreferCompatibilityProfile_SkWGLContextRequest, 126 /** Requests to create GL ES profile context. */ 127 kGLES_SkWGLContextRequest 128 }; 129 /** 130 * Helper to create an OpenGL context for a DC using WGL. Configs with a sample count >= to 131 * msaaSampleCount are preferred but if none is available then a context with a lower sample count 132 * (including non-MSAA) will be created. If msaaSampleCount is 1 then this will fail if a non-msaa 133 * context cannot be created. If preferCoreProfile is true but a core profile cannot be created 134 * then a compatible profile context will be created. 135 */ 136 HGLRC SkCreateWGLContext(HDC dc, int msaaSampleCount, bool deepColor, SkWGLContextRequest context, 137 HGLRC shareContext = nullptr); 138 139 /** 140 * Helper class for creating a pbuffer context and deleting all the handles when finished. This 141 * requires that a device context has been created. However, the pbuffer gets its own device 142 * context. The original device context can be released once the pbuffer context is created. 143 */ 144 class SkWGLPbufferContext : public SkRefCnt { 145 public: 146 static sk_sp<SkWGLPbufferContext> Create(HDC parentDC, SkWGLContextRequest contextType, 147 HGLRC shareContext); 148 149 ~SkWGLPbufferContext() override; 150 getDC()151 HDC getDC() const { return fDC; } getGLRC()152 HGLRC getGLRC() const { return fGLRC; } 153 154 private: 155 SkWGLPbufferContext(HPBUFFER pbuffer, HDC dc, HGLRC glrc); 156 157 HPBUFFER fPbuffer; 158 HDC fDC; 159 HGLRC fGLRC; 160 SkWGLExtensions fExtensions; 161 }; 162 163 #endif 164