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我的第1个OpenGL ES程序 for WinCE5 HTC TouchHD

cheungmine

中午吃过饭，闲来无事，看着我的手机（HTC TouchHD），忽然想编一个OpenGL程序玩玩。CSDN上下载了OpenGL ES的开发包。

解压之后发现了：bin/arm/Release目录下有几个文件：

              libGLES_CM.dll

              libGLES_CM.lib

              libGLES_CM.exp

等等。就准备把  libGLES_CM.dll  拷贝到我的手机的Windows下，提示已经有了这个文件，要不要覆盖？当然不覆盖。原来我的TouchHD支持OGL啊。太好了，马上编译例子Tutorial 1代码。其实就是新建一个Win32的移动程序空项目，平台是Windows Mobile 6.0Professional，然后把tutorial1.h和tutorial1.cpp文件拷贝到我的项目里，并添加到项目。编译不通过，提示文件目录不存在。马上添加包含目录和包含的库选项。编译通过。但是部署后，运行，失败。

网上搜，结果例子代码有问题，改正后的代码如下：

#ifndef _TUTORIAL1_H<br /> #define _TUTORIAL1_H<br /> #include <windows.h> //needed include for window system calls<br /> //OpenGL ES Includes<br /> #include <GLES/gl.h><br /> /*EGL is the "machine" that glues OpenGL ES with the underlying<br /> windowing system. We need it to create a suitable context and a drawable window*/<br /> #include <GLES/egl.h><br /> /*Because we are building software device dependent (the PDA), we have care about<br /> its limitations. PDA's doesn't have a FPU unit, so all floating point operations<br /> are emulated in the CPU. To have real data type, PDA's uses reals with a fixed point<br /> format. For a fixed point number we only need an integer, with the same size (in bytes)<br /> that a float, that is, a normal int number. The first 16 bits of the int will be the<br /> "integer" part, and the last 16 bits will be the "real" part. This will cause a lack<br /> of precision, but it is better than emulate all FPU in the CPU. To convert an integer<br /> number to a fixed point number we need to displace its bits to the left, as the FixedFromInt<br /> function does. In this chapter we only will need the conversion int->fixed point.<br /> Other conversions will be showed when needed, in later chapters. A complete description of<br /> the fixed point maths is beyond the purpose of this set of tutorials, but the topic will<br /> be widely covered through the chapters.<br /> OpenGL ES offers us a set of functions that works with fixed point (Glfixed). These<br /> functions are available through the OpenGL ES OES_fixed_point extension.<br /> A little word about the OpenGL ES extensions: They are divided into two categories:<br /> those that are fully integrated into the profile definition (core additions); and those<br /> that remain extensions (profile extensions). Core additions do not use extension suffixes<br /> and does not requires initialization, whereas profile extensions retain their extension suffixes.<br /> OES_fixed_point is a core addition. The other extensions are listed and explained in the<br /> OpenGL ES 1.1 specification.*/</p> <p>#define PRECISION 16<br /> #define ONE (1 << PRECISION)<br /> #define ZERO 0<br /> inline GLfixed FixedFromInt(int value) {return value << PRECISION;};<br /> int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, LPTSTR lpCmdLine,int nCmdShow);<br /> LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);<br /> BOOL InitOGLES();// Our GL initialization function<br /> void Render(); // Our Render function<br /> void Clean(); //Our clean function. It will clean all used resources<br /> #endif<br />

#include "tutorial1.h" //We need the defines and prototypes of there<br /> // cheungmine<br /> #pragma comment(lib, "E:/GU2005/GCE/OpenGL_ES_WCE/ogl-es-bin-0.83/dist/bin/arm/Debug/libGLES_CM.lib")<br /> //Some useful global handles<br /> HINSTANCE hInst; //Will hold the current instance of the application<br /> HWND hWnd; // A handle to the window we will create<br /> HDC hDC; // A handle to the device context of the window. Needed to<br /> //create the OpenGL ES context<br /> // OpenGL variables<br /> EGLDisplay glesDisplay; // EGL display<br /> EGLSurface glesSurface; // EGL rendering surface<br /> EGLContext glesContext; // EGL rendering context<br /> TCHAR szAppName[] = L"OpenGLES"; /*The application name and the window caption*/<br /> /*This is the WinMain function. Here we will create the rendering window, initialize OpenGL ES, write the message loop, and, at the end, clean all and release all used resources*/<br /> int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int nCmdShow)<br /> {<br /> MSG msg; //This is the message variable for the message loop<br /> WNDCLASS wc; /*This structure will hold some init values for our window*/<br /> hInst = hInstance; // Initialization of our global variable<br /> bool done = FALSE; </p> <p> /*This block of code is to ensure that the user only can run one<br /> instance of the application. First we search for a window with the<br /> same class name, if found, we will focus it and return*/<br /> if(hWnd = FindWindow(szAppName, szAppName))<br /> {<br /> /* Set focus to foremost child window. The "| 0x01" is used to<br /> bring any owned windows to the foreground and activate them.*/<br /> SetForegroundWindow((HWND)((ULONG) hWnd | 0x00000001));<br /> return 0;<br /> } </p> <p> wc.style = CS_HREDRAW | CS_VREDRAW; /*Will force a redraw<br /> if the window is resized, both horizontally or vertically*/<br /> wc.lpfnWndProc = (WNDPROC) WndProc; /*this is a function pointer,<br /> to tell the OS what function should call when a message needs to be<br /> processed*/<br /> wc.cbClsExtra = 0;<br /> wc.cbWndExtra = 0;<br /> wc.hInstance = hInstance;<br /> wc.hIcon = LoadIcon(hInstance, NULL);//Load default icon<br /> wc.hCursor = 0; // Default cursor<br /> wc.hbrBackground = 0; //We don't care about the background color<br /> wc.lpszMenuName = NULL; //This application does not have a menu<br /> wc.lpszClassName = szAppName; /*Important, here we must fill the<br /> application class name (the class name is not the same than the<br /> caption of the window, but many times they are the same)*/<br /> //Before creating the window, we must register this new window class<br /> if(!RegisterClass(&wc))<br /> return FALSE;</p> <p> hWnd=CreateWindow(szAppName, //Class Name<br /> szAppName, //Caption string<br /> WS_VISIBLE,//Window style<br /> CW_USEDEFAULT,CW_USEDEFAULT,//Starting [x,y] pos.<br /> CW_USEDEFAULT, CW_USEDEFAULT, //Width and height<br /> NULL, NULL, //Parent window and menu handle<br /> hInst, NULL); /*Instance handle. Custom value to<br /> pass in the creation with the WM_CREATE message*/</p> <p> if(!hWnd) return FALSE;<br /> if(!InitOGLES()) return FALSE; //OpenGL ES Initialization</p> <p> //Bring the window to front, focus it and refresh it<br /> ShowWindow(hWnd, nCmdShow);<br /> UpdateWindow(hWnd);</p> <p> //Message Loop<br /> while(!done)<br /> {<br /> if(PeekMessage(&msg,NULL,0,0,PM_REMOVE))<br /> {<br /> if(msg.message==WM_QUIT)<br /> done=TRUE;<br /> else<br /> {<br /> TranslateMessage(&msg);<br /> DispatchMessage(&msg);<br /> }<br /> }<br /> else<br /> Render();<br /> }<br /> //Clean up all<br /> Clean();<br /> return 0;<br /> }<br /> //----------------------------------------------------------------------------<br /> LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)<br /> {<br /> switch (message)<br /> {<br /> case WM_PAINT:<br /> ValidateRect(hWnd,NULL); //Needed to avoid new WM_PAINT messages<br /> return 0;<br /> case WM_DESTROY:<br /> PostQuitMessage(0);<br /> return 0;<br /> };<br /> return DefWindowProc(hWnd, message, wParam, lParam);<br /> }<br /> //----------------------------------------------------------------------------<br /> BOOL InitOGLES()<br /> {<br /> EGLint matchingConfigs; </p> <p> hDC = GetWindowDC(hWnd);<br /> glesDisplay = eglGetDisplay(hDC); //Ask for an available display<br /> if( glesDisplay == EGL_NO_DISPLAY || eglGetError() != EGL_SUCCESS )<br /> return FALSE;</p> <p> EGLConfig *configs_list;<br /> EGLint num_configs;<br /> // Display initialization (we don't care about the OGLES version numbers)<br /> if( eglInitialize( glesDisplay, NULL, NULL ) == EGL_FALSE || eglGetError() != EGL_SUCCESS )<br /> return FALSE;<br /> // find out how many configurations are supported<br /> if ( eglGetConfigs( glesDisplay, NULL, 0, &num_configs)==EGL_FALSE || eglGetError() != EGL_SUCCESS )<br /> return FALSE;<br /> configs_list = (EGLConfig*) malloc(num_configs * sizeof(EGLConfig));<br /> if (configs_list == NULL)<br /> return FALSE;<br /> // Get Configurations<br /> if( eglGetConfigs( glesDisplay, configs_list, num_configs, &num_configs)== EGL_FALSE || eglGetError() != EGL_SUCCESS )<br /> return FALSE;<br /> // Obtain the first configuration with a depth buffer of 16 bits<br /> EGLint attrs[3] = { EGL_DEPTH_SIZE, 16, EGL_NONE };<br /> if (!eglChooseConfig(glesDisplay, attrs, configs_list, num_configs, &matchingConfigs))<br /> {<br /> return eglGetError();<br /> }<br /> // If there isn't any configuration enough good<br /> if (matchingConfigs < 1)<br /> return FALSE;<br /> /*eglCreateWindowSurface creates an onscreen EGLSurface and returns<br /> a handle to it. Any EGL rendering context created with a<br /> compatible EGLConfig can be used to render into this surface.*/<br /> glesSurface = eglCreateWindowSurface(glesDisplay, configs_list[0], hWnd, 0);<br /> if(!glesSurface)<br /> return FALSE;</p> <p> // Let's create our rendering context<br /> glesContext=eglCreateContext(glesDisplay, configs_list[0], 0, 0);<br /> if(!glesContext)<br /> return FALSE;<br /> //Now we will activate the context for rendering<br /> eglMakeCurrent(glesDisplay, glesSurface, glesSurface, glesContext); </p> <p> /*Remember: because we are programming for a mobile device, we cant<br /> use any of the OpenGL ES functions that finish in 'f', we must use<br /> the fixed point version (they finish in 'x'*/<br /> glClearColorx(0, 0, 0, 0);<br /> glShadeModel(GL_SMOOTH);<br /> /*In order to set a viewport that fits entirely our window, we need<br /> to know the window dimensions. They could be obtained through the<br /> WinCE call GetWindowRect, using our window handle*/<br /> RECT r;<br /> GetWindowRect(hWnd, &r);<br /> glViewport(r.left, r.top, r.right - r.left, r.bottom - r.top); </p> <p> /*Setup of the projection matrix. We will use an ortho cube centered<br /> at (0,0,0) with 100 units of edge*/<br /> glMatrixMode(GL_PROJECTION);<br /> glLoadIdentity();<br /> glOrthox(FixedFromInt(-50), FixedFromInt(50),<br /> FixedFromInt(-50), FixedFromInt(50),<br /> FixedFromInt(-50), FixedFromInt(50));<br /> glMatrixMode(GL_MODELVIEW);<br /> glLoadIdentity();<br /> return TRUE;<br /> }<br /> //----------------------------------------------------------------------------<br /> void Render()<br /> {<br /> static int rotation = 0;<br /> /* Vertex 1 Vertex 2 Vertex 3*/<br /> GLshort vertexArray[9] = {-25,-25,0, 25,-25,0, 0,25,0 };<br /> GLubyte colorArray[12] = {255,0,0,0, 0,255,0,0, 0,0,255,0};</p> <p> glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);<br /> glLoadIdentity();<br /> glTranslatex(0, 0, FixedFromInt(-10));<br /> glRotatex(FixedFromInt(rotation++), 0, ONE,0);<br /> //Enable the vertices array<br /> glEnableClientState(GL_VERTEX_ARRAY);<br /> glVertexPointer(3, GL_SHORT, 0, vertexArray);<br /> //3 = XYZ coordinates, GL_SHORT = data type, 0 = 0 stride bytes</p> <p> //Enable the vertex color array<br /> glEnableClientState(GL_COLOR_ARRAY);<br /> glColorPointer(4,GL_UNSIGNED_BYTE, 0, colorArray);<br /> //4 = RGBA format, GL_UNSIGNED_BYTE = data type,0=0 stide bytes<br /> glDrawArrays(GL_TRIANGLES, 0, 3);<br /> /*We want draw triangles, 0 = first element(vertice), 3 = number of<br /> items (vertices) to draw from the array*/<br /> glDisableClientState(GL_VERTEX_ARRAY);<br /> glDisableClientState(GL_COLOR_ARRAY);</p> <p> eglSwapBuffers(glesDisplay, glesSurface);<br /> }<br /> //----------------------------------------------------------------------------<br /> void Clean()<br /> {<br /> if(glesDisplay)<br /> {<br /> eglMakeCurrent(glesDisplay, NULL, NULL, NULL);<br /> if(glesContext) eglDestroyContext(glesDisplay, glesContext);<br /> if(glesSurface) eglDestroySurface(glesDisplay, glesSurface);<br /> eglTerminate(glesDisplay);<br /> }<br /> //We have to destroy the window too<br /> DestroyWindow(hWnd);<br /> UnregisterClass(szAppName, hInst);<br /> }

运行，结果出来了，很好。一个OGL窗口在我的手机里。中间一个缓缓转动的三角形。

好了，该干活了。就闲扯到这里。以后我还会陆续发布一些OGL ES的东西，无论我自己写的还是抄来的，权作茶余饭后的消遣。

下面是我看过的链接：

http://sourceforge.net/projects/ogl-es/files/

http://wiki.forum.nokia.com/index.php/OpenGL_ES%E7%AE%80%E4%BB%8B

http://blog.csdn.net/dymx101/archive/2010/02/03/5284348.aspx

你会像我一样，从上面学到更多的知识。