OSG嵌入Win32窗口的例子

-----由ARRAY创作，，自由传播~~~~
下面是一个OSG嵌入Win32 API窗口的例子，我自己没事琢磨的~~应该有不少冗余和没用的地方，不过保证是可以用的~~在家里的豪华配置的电脑上（Intel Core 1.78G，Geforce7600GS）偶尔遇到帧速变得很慢的情形，不过在实验室的破机器上（AMD2600，Radeon7500）运行很流畅，呵呵，不知道是什么原因，还请大家指正~~

这个Win32API窗口的例子中，OSG的部分是参考MFC和其它GUI库的嵌入方法设计的，使用了Windows的多线程函数来执行osgViewer的渲染，这一点和MFC的例子相同。
Win32窗口的部分可以参照Win32窗口编程的任意一本书籍，架构都是基本一样的~~事实上研究Win32 API编程对于学习Windows本身极其有好处，而且像MiniGUI这样的GUI库也是模仿Win32 API窗口的函数来构建的，方便学习代码的移植~~
（虽然现在还不可能移植~~MiniGUI不支持OpenGL -______-）

下周可能还会有些事情，然后我打算对2.0版本的一些例子程序作注释，以利自己和大家学习；还有正在做一个OSG加工仿真相关的项目。
另外还有就是OSGQSG翻译的事：其实第三章已经翻译完成了，我和作者Paul Martz联系并获得CGSD的翻译授权之后，已经决定将中文版放在lulu.com（也就是大家下载英文版的地方）上供免费下载，这一工作预计将在数周后完成，主要是文字校对和排版的工作，到时候可能也有纸质的版本可供购买，呵呵，谢谢大家支持。（我不从中获益的，所以这个不算广告，呵呵~~）
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1. #include <windows.h>
2. #include <osgViewer/Viewer>
3. #include <osgViewer/ViewerEventHandlers>
4. #include <osgViewer/api/win32/GraphicsWindowWin32>
5. #include <osgUtil/Optimizer>
6. #include <osgGA/TrackballManipulator>
7. #include <osgDB/ReadFile>
8. #include <process.h>
10. osg::ref_ptr<osgViewer::Viewer> viewer;
11. osg::observer_ptr<osgViewer::GraphicsWindow> window;
12. osg::ref_ptr<osg::Group> root;
13. osg::ref_ptr<osg::Node> loadedModel;
14. osgUtil::Optimizer optimizer;
15. osg::ref_ptr<osg::GraphicsContext::Traits> traits;
16. osg::ref_ptr<osg::Referenced> windata;
17. osg::GraphicsContext* gc;
18. osg::ref_ptr<osg::Camera> camera;
20. bool renderok;
22. LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
24. int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow)
25. {
26. static TCHAR szAppName[] = TEXT("HelloWin");
27. HWND hwnd;
28. MSG msg;
29. WNDCLASS wndclass;
31. wndclass.style = CS_HREDRAW | CS_VREDRAW;
32. wndclass.lpfnWndProc = WndProc;
33. wndclass.cbClsExtra = 0;
34. wndclass.cbWndExtra = 0;
35. wndclass.hInstance = hInstance;
36. wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
37. wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
38. wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
39. wndclass.lpszMenuName = NULL;
40. wndclass.lpszClassName = szAppName;
42. if (!RegisterClass(&wndclass))
43. {
44. MessageBox(NULL, TEXT("This program requires Windows NT!"), szAppName, MB_ICONERROR);
45. return 0;
46. }
48. hwnd = CreateWindow( szAppName, // window class name
49. TEXT ("The Hello Program"), // window caption
50. WS_OVERLAPPEDWINDOW, // window style
51. 100, // initial x position
52. 100, // initial y position
53. 800, // initial x size
54. 600, // initial y size
55. NULL, // parent window handle
56. NULL, // window menu handle
57. hInstance, // program instance handle
58. NULL); // creation parameters
60. ShowWindow(hwnd, iCmdShow);
61. UpdateWindow(hwnd);
63. while (GetMessage(&msg, NULL, 0, 0))
64. {
65. TranslateMessage(&msg);
66. DispatchMessage(&msg);
67. }
69. return (int)msg.wParam;
70. }
72. void render(void* ptr)
73. {
74. while (!viewer->done())
75. {
76. viewer->frame();
77. }
79. renderok = true;
80. }
82. LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
83. {
84. switch (message)
85. {
86. case WM_CREATE:
87. root = new osg::Group;
88. loadedModel = osgDB::readNodeFile("D:/OpenSceneGraph/bin/exe/cessna.osg");
89. if (!loadedModel)
90. return 1;
91. optimizer.optimize(loadedModel.get());
92. optimizer.reset();
93. root->addChild(loadedModel.get());
95. traits = new osg::GraphicsContext::Traits;
96. windata = new osgViewer::GraphicsWindowWin32::WindowData(hwnd);
97. traits->x = 0;
98. traits->y = 0;
99. traits->width = 800;
100. traits->height = 600;
101. traits->windowDecoration = false;
102. traits->doubleBuffer = true;
103. traits->sharedContext = 0;
104. traits->inheritedWindowData = windata;
105. traits->setInheritedWindowPixelFormat = true;
106. gc = osg::GraphicsContext::createGraphicsContext(traits.get());
108. camera = new osg::Camera;
109. camera->setGraphicsContext(gc);
110. camera->setViewport(new osg::Viewport(traits->x, traits->y, traits->width, traits->height));
112. viewer = new osgViewer::Viewer;
113. viewer->addSlave(camera.get());
114. viewer->setSceneData(root.get());
115. viewer->setCameraManipulator(new osgGA::TrackballManipulator);
116. viewer->addEventHandler(new osgViewer::StatsHandler);
117. viewer->setThreadingModel(osgViewer::Viewer::SingleThreaded);
118. viewer->realize();
120. renderok = false;
121. _beginthread(render, 0, NULL);
122. return 0;
124. case WM_PAINT:
125. return 0;
127. case WM_DESTROY:
128. viewer->setDone(true);
129. while (!renderok)
130. {
131. Sleep(10);
132. }
134. PostQuitMessage(0);
135. return 0;
136. }
138. return DefWindowProc(hwnd, message, wParam, lParam);
139. }

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