在多文档应用程序中使用OpenGL绘图

1、在视图类的头文件中添加两个成员变量：

[code]     [code] public:

int m_GLPixelIndex;

HGLRC m_hGLContext;

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2、在视图类的构造函数中对这两个成员进行初始化：

[code]
[code] m_GLPixelIndex = 0;

m_hGLContext = NULL;

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3、在视图类声明中添加两个成员函数：

[code]
[code] BOOL SetWindowPixelFormat(HDC hDC);

BOOL CreateViewGLContext(HDC hDC);

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4、在视图类的实现文件中添加这两个成员函数的实现：

[code]
[code] BOOL CXXXView::CreateViewGLContext(HDC hDC)

{

m_hGLContext = wglCreateContext(hDC);

if(m_hGLContext==NULL)

return FALSE;

if(wglMakeCurrent(hDC,m_hGLContext)==FALSE)

return FALSE;

return TRUE;

}

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以及

[code]
[code] BOOL CXXXView::SetWindowPixelFormat(HDC hDC)

{

PIXELFORMATDESCRIPTOR pixelDesc;

pixelDesc.nSize = sizeof(PIXELFORMATDESCRIPTOR);

pixelDesc.nVersion = 1;

pixelDesc.dwFlags = PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL |

PFD_DOUBLEBUFFER | PFD_STEREO_DONTCARE;

pixelDesc.iPixelType = PFD_TYPE_RGBA;

pixelDesc.cColorBits = 32;

pixelDesc.cRedBits = 8;

pixelDesc.cRedShift = 16;

pixelDesc.cGreenBits = 8;

pixelDesc.cGreenShift = 8;

pixelDesc.cBlueBits = 8;

pixelDesc.cBlueShift = 0;

pixelDesc.cAlphaBits = 0;

pixelDesc.cAlphaShift = 0;

pixelDesc.cAccumBits = 64;

pixelDesc.cAccumRedBits = 16;

pixelDesc.cAccumGreenBits = 16;

pixelDesc.cAccumBlueBits = 16;

pixelDesc.cAccumAlphaBits = 0;

pixelDesc.cDepthBits = 32;

pixelDesc.cStencilBits = 8;

pixelDesc.cAuxBuffers = 0;

pixelDesc.iLayerType = PFD_MAIN_PLANE;

pixelDesc.bReserved = 0;

pixelDesc.dwLayerMask = 0;

pixelDesc.dwVisibleMask = 0;

pixelDesc.dwDamageMask = 0;

m_GLPixelIndex = ChoosePixelFormat(hDC,&pixelDesc);

if(m_GLPixelIndex == 0) // Choose default

  {

m_GLPixelIndex = 1;

if(DescribePixelFormat(hDC,m_GLPixelIndex,

sizeof(PIXELFORMATDESCRIPTOR),&pixelDesc)==0)

    return FALSE;

  }

if(!SetPixelFormat(hDC,m_GLPixelIndex,&pixelDesc))

return FALSE;

return TRUE;

}

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在视图类的OnCreate成员函数中添加：

[code]
[code] HWND hWnd = GetSafeHwnd();

HDC hDC = ::GetDC(hWnd);

if(SetWindowPixelFormat(hDC)==FALSE)

return -1;

if(CreateViewGLContext(hDC)==FALSE)

return -1;

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添加OnPaint消息响应函数，在函数中加入：

[code]
[code] HWND hWnd = GetSafeHwnd();

HDC hDC = ::GetDC(hWnd);

wglMakeCurrent(dc.m_ps.hdc,m_hGLContext);

....

// Double buffer

SwapBuffers(dc.m_ps.hdc);

glFlush();

// release

::ReleaseDC(hWnd,hDC);

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添加OnSize消息响应函数。这里的内容可以根据需要进行修改：

[code]
[code] glViewport(0,0,(GLsizei)cx,(GLsizei)cy);

glMatrixMode(GL_PROJECTION);

glLoadIdentity();

gluPerspective(60.0,(GLfloat)cx/(GLfloat)cy,0.1,100.0);

glMatrixMode(GL_MODELVIEW);

glLoadIdentity();

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添加虚函数OnActivateView，在其中添加：

[code]
[code] HWND hWnd = GetSafeHwnd();

HDC hDC = ::GetDC(hWnd);

wglMakeCurrent(hDC,m_hGLContext);

::ReleaseDC(hWnd,hDC);

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添加WM_DESTROY消息响应函数，在其中添加：

[code]
[code] if(wglGetCurrentContext() != NULL)

wglMakeCurrent(NULL,NULL);

if(m_hGLContext != NULL)

{

wglDeleteContext(m_hGLContext);

    m_hGLContext = NULL;

}

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Over。