OpenGL（三）MFC中应用OpenGL的两个类

网上找了下MFC中应用OpenGL的方法，总觉得不太方便，到处复制一堆堆函数，于是封装了两个类（CmyOpenGL和CRenderContex）。方便应用。
以MFC Dialog为例添加步骤：
- CXXXDlg中添加一CmyOpenGL成员（或指针，别忘记释放就行）
- 将三个成员函数对应加入（OnCreate、OnPaint、OnSize）MFC的消息映射函数中，传递相应参数（CmyOpenGL要利用CDC*所指对象，因此CDC*要在CmyOpenGL对象之后释放！）

代码：

CmyOpenGL.h

 1 #pragma once
 2 #include "RenderContex.h"
 3 
 4 class CmyOpenGL
 5 {
 6 public:
 7     CmyOpenGL(void);
 8     virtual ~CmyOpenGL(void);
 9 public:
10     virtual void OnCreate(CDC* pDC);
11     virtual void OnPaint(void);
12     virtual void OnSize(int cx, int cy);
13 private:
14     virtual void RenderScene (void);
15 private:
16     CDC* m_pDC;
17     CRenderContex* m_pRC;
18 };

CmyOpenGL.cpp

 1 #include "StdAfx.h"
 2 #include "myOpenGL.h"
 3 
 4 CmyOpenGL::CmyOpenGL(void)
 5 {
 6     m_pDC = NULL;
 7     m_pRC = NULL;
 8 }
 9 
10 CmyOpenGL::~CmyOpenGL(void)
11 {
12     if (m_pRC)
13     {
14         delete m_pRC;
15     }
16     m_pRC = NULL;
17 }
18 
19 void CmyOpenGL::OnCreate(CDC* pDC)
20 {
21     ASSERT(pDC);
22     m_pRC = new CRenderContex(pDC);
23     ASSERT(m_pRC);
24 
25     m_pDC = pDC;
26 
27     //Specify Black as the clear color
28     ::glClearColor(0.0f,0.0f,0.0f,0.0f);
29 }
30 
31 void CmyOpenGL::OnPaint()
32 {
33     // Clear out the color & depth buffers
34     ::glClear( GL_COLOR_BUFFER_BIT);
35     RenderScene();
36     // Tell OpenGL to flush its pipeline
37     ::glFinish();
38     // Now Swap the buffers
39     ::SwapBuffers( m_pDC->GetSafeHdc() );
40 }
41 
42 void CmyOpenGL::OnSize(int cx, int cy)
43 {
44     if ( 0 >= cx || 0 >= cy )
45     {
46         return;
47     }
48     // select the full client area
49     ::glViewport(0, 0, cx, cy);
50     // select the projection matrix and clear it
51     ::glMatrixMode(GL_PROJECTION);
52     ::glLoadIdentity();
53     // select the viewing volume
54     ::gluPerspective(45.0f, (GLdouble)cx/(GLdouble)cy, 1.0f, 100.0f);
55     // switch back to the modelview matrix and clear it
56     ::glMatrixMode(GL_MODELVIEW);
57     ::glLoadIdentity();
58 }
59 
60 void CmyOpenGL::RenderScene (void)
61 {
62     glTranslatef(0.0f, 0.0f, -5.0f);
63     glRotatef(45.0,0.0,1.0,0.0);
64     glutWireCube(1.0);
65 }

CRenderContex.h

 1 #pragma once
 2 
 3 class CRenderContex
 4 {
 5 public:
 6     CRenderContex(CDC *pDC);
 7     ~CRenderContex(void);
 8 private:
 9     BOOL SetupPixelFormat(CDC *pDC);    //Set up the Pixel Format
10 private:
11     HGLRC m_hRC;
12 };

CRenderContex.cpp

 1 #include "StdAfx.h"
 2 #include "RenderContex.h"
 3 
 4 CRenderContex::CRenderContex(CDC *pDC)
 5 {
 6     ASSERT(pDC);
 7 
 8     BOOL bResult = FALSE;
 9     bResult = SetupPixelFormat(pDC);
10     ASSERT(bResult);
11 
12     //Create Rendering Context
13     m_hRC = ::wglCreateContext (pDC->GetSafeHdc ());
14     ASSERT(m_hRC);
15     //Make the RC Current
16     bResult = ::wglMakeCurrent (pDC->GetSafeHdc (), m_hRC);
17     ASSERT(bResult);
18 }
19 
20 CRenderContex::~CRenderContex(void)
21 {
22     BOOL bResult = FALSE;
23     //Make the RC non-current
24     bResult = ::wglMakeCurrent (0,0);
25     ASSERT(bResult);
26 
27     //Delete the rendering context
28     bResult = ::wglDeleteContext (m_hRC);
29     ASSERT(bResult);
30 }
31 
32 //Setup Pixel Format
33 BOOL CRenderContex::SetupPixelFormat(CDC *pDC)
34 {
35     static PIXELFORMATDESCRIPTOR pfd = 
36     {
37         sizeof(PIXELFORMATDESCRIPTOR),  // size of this pfd
38         1,                              // version number
39         PFD_DRAW_TO_WINDOW |            // support window
40         PFD_SUPPORT_OPENGL |            // support OpenGL
41         PFD_DOUBLEBUFFER,               // double buffered
42         PFD_TYPE_RGBA,                  // RGBA type
43         24,                             // 24-bit color depth
44         0, 0, 0, 0, 0, 0,               // color bits ignored
45         0,                              // no alpha buffer
46         0,                              // shift bit ignored
47         0,                              // no accumulation buffer
48         0, 0, 0, 0,                     // accum bits ignored
49         16,                             // 16-bit z-buffer
50         0,                              // no stencil buffer
51         0,                              // no auxiliary buffer
52         PFD_MAIN_PLANE,                 // main layer
53         0,                              // reserved
54         0, 0, 0                         // layer masks ignored
55     };
56     int m_nPixelFormat = ::ChoosePixelFormat(pDC->GetSafeHdc(), &pfd);
57     if ( m_nPixelFormat == 0 )
58     {
59         return FALSE;
60     }
61     if ( ::SetPixelFormat(pDC->GetSafeHdc(), m_nPixelFormat, &pfd) == FALSE)
62     {
63         return FALSE;
64     }
65     return TRUE;
66 }

参考：http://www.cnblogs.com/phinecos/archive/2008/11/04/1326687.html