初始化glew，创建OpenGL渲染上下文

 1 void RegisterWinDowClass(HINSTANCE hInstance,std::string className,WNDPROC proc)
 2 {
 3     WNDCLASS wndClass;
 4     wndClass.cbClsExtra = 0;
 5     wndClass.cbWndExtra = 0;
 6     wndClass.hbrBackground = (HBRUSH)::GetStockObject(GRAY_BRUSH);
 7     wndClass.hCursor = ::LoadCursor(NULL,IDC_ARROW);
 8     wndClass.hIcon = ::LoadIcon(NULL,IDI_APPLICATION);
 9     wndClass.hInstance = hInstance;
10     wndClass.lpfnWndProc = proc;
11     wndClass.lpszClassName = className.c_str();
12     wndClass.lpszMenuName = NULL;
13     wndClass.style = CS_HREDRAW | CS_VREDRAW | CS_OWNDC | CS_DBLCLKS;
14     ::RegisterClass(&wndClass);
15 }

 1 bool InitGlewLib(HINSTANCE hInstance)
 2 {
 3     RegisterWinDowClass(hInstance,"Fake",MainWinProc);
 4
 5     HWND hWnd = ::CreateWindow("Fake","OpenGL",WS_OVERLAPPEDWINDOW,
 6         CW_USEDEFAULT,CW_USEDEFAULT,width,heigtht,
 7         NULL,NULL,hInstance,NULL);
 8
 9     HDC hDC = ::GetDC(hWnd);
10     HGLRC hRc;
11     ::PIXELFORMATDESCRIPTOR pfd;
12     //memset(&pfd,0,sizeof(pfd));
13
14     //pfd.nVersion = 1;
15     //pfd.nSize = sizeof(PIXELFORMATDESCRIPTOR);
16     //pfd.dwFlags = PFD_DOUBLEBUFFER | PFD_SUPPORT_OPENGL | PFD_DRAW_TO_WINDOW;
17     //pfd.iPixelType = PFD_TYPE_RGBA;
18     //pfd.cColorBits = 32;
19     //pfd.cDepthBits = 32;
20     //pfd.iLayerType = PFD_MAIN_PLANE;
21
22     //int iPixelFormat = ::ChoosePixelFormat(hDC,&pfd);
23     //if (iPixelFormat == 0)
24     //{
25     //    DestroyWindow(hWnd);
26     //    return false;
27     //}
28     /**************************************************************************
29
30     1，注册fake窗口的class，如果和主窗口是同名的class，会使初始化失败
31     2，选择1号格式索引作为临时索引
32     3，根据设备上下文创建渲染上下文
33     4，绑定到当前上下文
34     5，初始化glew
35     6，解除上下文绑定，销毁窗口
36     **************************************************************************/
37
38     int iPixelFormat = 1;
39     if (::SetPixelFormat(hDC,iPixelFormat,&pfd))
40     {
41         hRc = ::wglCreateContext(hDC);
42         if (::wglMakeCurrent(hDC,hRc))
43         {
44             GLenum retVal = glewInit();
45             wglMakeCurrent(NULL,NULL);
46             wglDeleteContext(hRc);
47             DestroyWindow(hWnd);
48             return retVal == GLEW_OK;
49         }
50         wglDeleteContext(hRc);
51         DestroyWindow(hWnd);
52     }
53     else
54     {
55         DestroyWindow(hWnd);
56     }
57
58     return false;
59 }

 1 bool InitOpenGL(HWND hWnd,HINSTANCE hInstance)
 2 {
 3     if (!InitGlewLib(hInstance))
 4     {
 5         ::MessageBox(NULL,"glew init Error",NULL,MB_OK);
 6         return 0;
 7     }
 8
 9     if(!WGLEW_ARB_create_context || !WGLEW_ARB_pixel_format)
10         return false;
11     HDC hDC = ::GetDC(hWnd);
12     PIXELFORMATDESCRIPTOR pfd;
13     //memset(&pfd, 0, sizeof(PIXELFORMATDESCRIPTOR));
14     //pfd.nSize        = sizeof(PIXELFORMATDESCRIPTOR);
15     //pfd.nVersion   = 1;
16     //pfd.dwFlags    = PFD_DOUBLEBUFFER | PFD_SUPPORT_OPENGL | PFD_DRAW_TO_WINDOW;
17     //pfd.iPixelType = PFD_TYPE_RGBA;
18     //pfd.cColorBits = 32;
19     //pfd.cDepthBits = 32;
20     //pfd.iLayerType = PFD_MAIN_PLANE;
21
22     /**************************************************************************
23
24     1，填充像素格式属性 （缓冲区的初始化）
25     2，填充上下文属性 （用于设置指定OpenGL版本）
26     3，根据像素格式属性选择设备上下文合适像素格式索引。wglChoosePixelFormatARB(...)
27     4，将得到的像素格式索引绑定到设备上下文。SetPixelFormat(...)
28     5，根据设备上下文，及上下文属性设置创建一个OpenGL渲染上下文。wglCreateContextAttribsARB(...)
29     6，将渲染上下文与设备上下文绑定 wglMakeCurrent(...)
30
31     **************************************************************************/
32
33     const int iPixelFormatAttributeList[] =
34     {
35         WGL_DRAW_TO_WINDOW_ARB, GL_TRUE,                        // 绘制到窗口
36         WGL_SUPPORT_OPENGL_ARB,GL_TRUE,                            // 支持OpenGL
37         WGL_ACCELERATION_ARB ,WGL_FULL_ACCELERATION_ARB ,        // 硬件加速
38         WGL_DOUBLE_BUFFER_ARB,GL_TRUE,                            // 双缓冲
39         WGL_PIXEL_TYPE_ARB,WGL_TYPE_RGBA_ARB,                    // RGBA
40         WGL_COLOR_BITS_ARB,32,                                    // 颜色位数32
41         WGL_DEPTH_BITS_ARB,24,                                    // 深度位数24
42         WGL_STENCIL_BITS_ARB,8,                                    // 模板位数8
43         WGL_SWAP_METHOD_ARB, WGL_SWAP_EXCHANGE_ARB,                // 双缓冲swap方式直接交换
44         WGL_SAMPLE_BUFFERS_ARB, 4,                                // 4倍抗锯齿
45         0
46     };
47
48     const int iContextAttributeList[] =
49     {
50         WGL_CONTEXT_MAJOR_VERSION_ARB,3,                        // 主版本号
51         WGL_CONTEXT_MINOR_VERSION_ARB,3,                        // 次版本号
52         WGL_CONTEXT_FLAGS_ARB,WGL_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB,
53         0
54     };
55
56     int iPixelFormat,iNumFormat;
57     wglChoosePixelFormatARB(hDC,iPixelFormatAttributeList,NULL,
58         1,&iPixelFormat,(UINT *)&iNumFormat);
59
60     if (!SetPixelFormat(hDC,iPixelFormat,&pfd))
61     {
62         //int error = ::GetLastError();
63         return false;
64     }
65     HGLRC hRC = wglCreateContextAttribsARB(hDC,NULL,iContextAttributeList);
66     if (hRC)
67     {
68         ::wglMakeCurrent(hDC,hRC);
69         return true;
70     }
71     return false;
72 }