/* * Copyright 2011 Google Inc. * * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file. */ #include "SkRefCnt.h" #ifndef SkWGL_DEFINED #define SkWGL_DEFINED /** * Working with WGL extensions can be a pain. Among the reasons is that You must * have a GL context to get the proc addresses, but you want to use the procs to * create a context in the first place. So you have to create a dummy GL ctx to * get the proc addresses. * * This file helps by providing SkCreateWGLInterface(). It returns a struct of * function pointers that it initializes. It also has a helper function to query * for WGL extensions. It handles the fact that wglGetExtensionsString is itself * an extension. */ #if !defined(WIN32_LEAN_AND_MEAN) #define WIN32_LEAN_AND_MEAN #define SK_LOCAL_LEAN_AND_MEAN #endif #include <windows.h> #if defined(SK_LOCAL_LEAN_AND_MEAN) #undef WIN32_LEAN_AND_MEAN #undef SK_LOCAL_LEAN_AND_MEAN #endif #define SK_WGL_DRAW_TO_WINDOW 0x2001 #define SK_WGL_ACCELERATION 0x2003 #define SK_WGL_SUPPORT_OPENGL 0x2010 #define SK_WGL_DOUBLE_BUFFER 0x2011 #define SK_WGL_COLOR_BITS 0x2014 #define SK_WGL_ALPHA_BITS 0x201B #define SK_WGL_STENCIL_BITS 0x2023 #define SK_WGL_FULL_ACCELERATION 0x2027 #define SK_WGL_SAMPLE_BUFFERS 0x2041 #define SK_WGL_SAMPLES 0x2042 #define SK_WGL_CONTEXT_MAJOR_VERSION 0x2091 #define SK_WGL_CONTEXT_MINOR_VERSION 0x2092 #define SK_WGL_CONTEXT_LAYER_PLANE 0x2093 #define SK_WGL_CONTEXT_FLAGS 0x2094 #define SK_WGL_CONTEXT_PROFILE_MASK 0x9126 #define SK_WGL_CONTEXT_DEBUG_BIT 0x0001 #define SK_WGL_CONTEXT_FORWARD_COMPATIBLE_BIT 0x0002 #define SK_WGL_CONTEXT_CORE_PROFILE_BIT 0x00000001 #define SK_WGL_CONTEXT_COMPATIBILITY_PROFILE_BIT 0x00000002 #define SK_WGL_CONTEXT_ES2_PROFILE_BIT 0x00000004 #define SK_ERROR_INVALID_VERSION 0x2095 #define SK_ERROR_INVALID_PROFILE 0x2096 class SkWGLExtensions { public: SkWGLExtensions(); /** * Determines if an extensions is available for a given DC. * WGL_extensions_string is considered a prerequisite for all other * extensions. It is necessary to check this before calling other class * functions. */ bool hasExtension(HDC dc, const char* ext) const; const char* getExtensionsString(HDC hdc) const; BOOL choosePixelFormat(HDC hdc, const int*, const FLOAT*, UINT, int*, UINT*) const; BOOL getPixelFormatAttribiv(HDC, int, int, UINT, const int*, int*) const; BOOL getPixelFormatAttribfv(HDC hdc, int, int, UINT, const int*, FLOAT*) const; HGLRC createContextAttribs(HDC, HGLRC, const int *) const; /** * WGL doesn't have precise rules for the ordering of formats returned * by wglChoosePixelFormat. This function helps choose among the set of * formats returned by wglChoosePixelFormat. The rules in decreasing * priority are: * * Choose formats with the smallest sample count that is >= * desiredSampleCount (or the largest sample count if all formats have * fewer samples than desiredSampleCount.) * * Choose formats with the fewest color samples when coverage sampling * is available. * * If the above rules leave multiple formats, choose the one that * appears first in the formats array parameter. */ int selectFormat(const int formats[], int formatCount, HDC dc, int desiredSampleCount); private: typedef const char* (WINAPI *GetExtensionsStringProc)(HDC hdc); typedef BOOL (WINAPI *ChoosePixelFormatProc)(HDC hdc, const int *, const FLOAT *, UINT, int *, UINT *); typedef BOOL (WINAPI *GetPixelFormatAttribivProc)(HDC, int, int, UINT, const int*, int*); typedef BOOL (WINAPI *GetPixelFormatAttribfvProc)(HDC hdc, int, int, UINT, const int*, FLOAT*); typedef HGLRC (WINAPI *CreateContextAttribsProc)(HDC hDC, HGLRC, const int *); GetExtensionsStringProc fGetExtensionsString; ChoosePixelFormatProc fChoosePixelFormat; GetPixelFormatAttribfvProc fGetPixelFormatAttribfv; GetPixelFormatAttribivProc fGetPixelFormatAttribiv; CreateContextAttribsProc fCreateContextAttribs; }; /** * Helper to create an OpenGL context for a DC using WGL. Configs with a sample count >= to * msaaSampleCount are preferred but if none is available then a context with a lower sample count * (including non-MSAA) will be created. If preferCoreProfile is true but a core profile cannot be * created then a compatible profile context will be created. */ HGLRC SkCreateWGLContext(HDC dc, int msaaSampleCount, bool preferCoreProfile); #endif