WinCE OpenGL繪制立方體和紋理貼圖
最近工作之余,開始學(xué)習(xí)OpenGL, 想到WINCE也是支持OpenGL的,只不過是嵌入式的OpenGL ES.于是嘗試寫了一個WINCE下的OpenGL測試程序,實現(xiàn)了繪制立方體和紋理。效果圖如下:
需要注意的是,WINCE系統(tǒng)上開發(fā)OpenGL程序需具備以下條件:
1. 處理器的支持,嵌入式處理器需支持3D加速渲染。
2. WINCE內(nèi)核的支持,定制內(nèi)核時需添加OpenGL ES相關(guān)組件。
以下是具體的參考代碼:
view plain /******************************************************************** filename: WinceOpenGLDemo.cpp created: 2011-01-05 author: firehood purpose: 利用OpenGL ES實現(xiàn)了繪制立方體和紋理效果*********************************************************************/
// WinceOpenGLDemo.cpp : 定義應(yīng)用程序的入口點。
//
#include "stdafx.h" #include "WinceOpenGLDemo.h" #include
// OpenGL lib #pragma comment(lib, "OpenGlLib\libGLESv1_CM.lib")
#pragma comment(lib, "OpenGlLib\libEGL.lib")
// 全局變量:HINSTANCE g_hInst; // 當(dāng)前實例TCHAR szAppName[] = L"OpenGLES"; /*The application name and the window caption*/ CImgLoader g_Image;// OpenGL variables EGLDisplay glesDisplay; // EGL display EGLSurface glesSurface; // EGL rendering surface EGLContext glesContext; // EGL rendering context
GLuint texture[6] = {0};
// 立方體定點坐標(biāo)GLshort vertices[] = { -1,-1,1,1,-1,1,1,1,1,-1,1,1,
-1,-1,-1,-1,1,-1,1,1,-1,1,-1,-1,
-1,1,-1,-1,1,1,1,1,1,1,1,-1,
-1,-1,-1,1,-1,-1,1,-1,1,-1,-1,1,
1,-1,-1,1,1,-1,1,1,1,1,-1,1,
-1,-1,-1,-1,-1,1,-1,1,1,-1,1,-1 };
// 各個面紋理坐標(biāo)GLshort texCoords[] = { 0,0,1,0,1,1,0,1,};
// 三角形索引數(shù)據(jù)GLbyte indices1[] = { 0,1,3,2,0,0,0,0,0,0,0,0 };GLbyte indices2[] = { 0,0,0,0,4,5,7,6,0,0,0,0,0,0,0,0 };GLbyte indices3[] = { 0,0,0,0,8,9,11,10,0,0,0,0,0,0,0,0 };GLbyte indices4[] = { 0,0,0,0,12,13,15,14,0,0,0,0,0,0,0,0 };GLbyte indices5[] = { 0,0,0,0,16,17,19,18,0,0,0,0 };GLbyte indices6[] = { 0,0,0,0,20,21,23,22 };
// 此代碼模塊中包含的函數(shù)的前向聲明:ATOM MyRegisterClass(HINSTANCE, LPTSTR);BOOL InitInstance(HINSTANCE, int);LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
BOOL InitOGLES(HWND hWnd);void CreateSurface();BOOL LoadTexture(LPCTSTR lpFileName,GLuint *id);void Render();void Clean();
int WINAPI WinMain(HINSTANCE hInstance,HINSTANCE hPrevInstance,LPTSTR lpCmdLine,int nCmdShow)
{ MSG msg;
// 執(zhí)行應(yīng)用程序初始化:if (!InitInstance(hInstance, nCmdShow))
{ return FALSE;}
BOOL done = FALSE;// 主消息循環(huán):while(!done)
{ if(PeekMessage(&msg,NULL,0,0,PM_REMOVE))
{ if(msg.message==WM_QUIT)
done = TRUE;else { TranslateMessage(&msg);DispatchMessage(&msg);} else { Render();};}
return (int) msg.wParam;}
// // 函數(shù): MyRegisterClass()
// // 目的: 注冊窗口類。
// // 注釋:// ATOM MyRegisterClass(HINSTANCE hInstance, LPTSTR szWindowClass)
{ WNDCLASS wc;
wc.style = CS_HREDRAW | CS_VREDRAW;wc.lpfnWndProc = WndProc;wc.cbClsExtra = 0;wc.cbWndExtra = 0;wc.hInstance = hInstance;wc.hIcon = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_WINCEOPENGLDEMO));wc.hCursor = 0;wc.hbrBackground = (HBRUSH) GetStockObject(NULL_BRUSH);wc.lpszMenuName = 0;wc.lpszClassName = szWindowClass;
return RegisterClass(&wc);}
// // 函數(shù): InitInstance(HINSTANCE, int)
// // 目的: 保存實例句柄并創(chuàng)建主窗口// // 注釋:// // 在此函數(shù)中,我們在全局變量中保存實例句柄并// 創(chuàng)建和顯示主程序窗口。
// BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
{ HWND hWnd;
g_hInst = hInstance; // 將實例句柄存儲在全局變量中
if (!MyRegisterClass(hInstance, szAppName))
{ return FALSE;}
hWnd = CreateWindow(szAppName,WS_VISIBLE,0,::GetSystemMetrics(SM_CXSCREEN),::GetSystemMetrics(SM_CYSCREEN),NULL,hInstance,NULL);
if (!hWnd)
{ return FALSE;}
if(!InitOGLES(hWnd))
{ printf("InitOGLES failedn");return FALSE;} CreateSurface();
ShowWindow(hWnd, SW_SHOW);UpdateWindow(hWnd);
return TRUE;}
// // 函數(shù): WndProc(HWND, UINT, WPARAM, LPARAM)
// // 目的: 處理主窗口的消息。
// // WM_COMMAND - 處理應(yīng)用程序菜單// WM_PAINT - 繪制主窗口// WM_DESTROY - 發(fā)送退出消息并返回// LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)[!--empirenews.page--]
{ PAINTSTRUCT ps;HDC hdc;
switch (message)
{ case WM_CREATE:break;case WM_PAINT:hdc = BeginPaint(hWnd, &ps);
// TODO: 在此添加任意繪圖代碼……
EndPaint(hWnd, &ps);break;case WM_DESTROY:{ Clean();PostQuitMessage(0);} break;
default:return DefWindowProc(hWnd, message, wParam, lParam);} return 0;}
BOOL InitOGLES(HWND hWnd)
{ EGLint matchingConfigs;EGLint majorVersion = 0;EGLint minorVersion = 0;
glesDisplay = eglGetDisplay(GetDC(hWnd)); //Ask for an available display if( glesDisplay == EGL_NO_DISPLAY || eglGetError() != EGL_SUCCESS )
return FALSE;
EGLConfig *configs_list;EGLint num_configs;// Display initialization (we don‘t care about the OGLES version numbers)
if( eglInitialize( glesDisplay, &majorVersion, &minorVersion) == EGL_FALSE)
{ printf("eglInitialize failed, eglGetError = 0x%04xn",eglGetError());return FALSE;} // find out how many configurations are supported if ( eglGetConfigs( glesDisplay, NULL, 0, &num_configs)==EGL_FALSE || eglGetError() != EGL_SUCCESS )
return FALSE;configs_list = (EGLConfig*) malloc(num_configs * sizeof(EGLConfig));if (configs_list == NULL)
return FALSE;// Get Configurations if( eglGetConfigs( glesDisplay, configs_list, num_configs, &num_configs)== EGL_FALSE || eglGetError() != EGL_SUCCESS )
return FALSE;// Obtain the first configuration with a depth buffer of 16 bits EGLint attrs[] = { EGL_RED_SIZE, 5,EGL_GREEN_SIZE, 6,EGL_BLUE_SIZE, 5,EGL_DEPTH_SIZE, 16,EGL_NONE };if (!eglChooseConfig(glesDisplay, attrs, configs_list, num_configs, &matchingConfigs))
{ return eglGetError();} // If there isn‘t any configuration enough good if (matchingConfigs < 1)
return FALSE;/*eglCreateWindowSurface creates an onscreen EGLSurface and returns a handle to it. Any EGL rendering context created with a compatible EGLConfig can be used to render into this surface.*/ glesSurface = eglCreateWindowSurface(glesDisplay, configs_list[0], hWnd, 0);if(!glesSurface)
return FALSE;
// Let‘s create our rendering context glesContext=eglCreateContext(glesDisplay, configs_list[0], 0, 0);if(!glesContext)
return FALSE;//Now we will activate the context for rendering eglMakeCurrent(glesDisplay, glesSurface, glesSurface, glesContext);
/*Remember: because we are programming for a mobile device, we cant use any of the OpenGL ES functions that finish in ‘f‘, we must use the fixed point version (they finish in ‘x‘*/ glClearColorx(0, 0, 0, 0);glShadeModel(GL_SMOOTH);
RECT rc;GetWindowRect(hWnd, &rc);UINT width = rc.right - rc.left;UINT height = rc.bottom - rc.top;// 設(shè)置OpenGL場景的大小glViewport(rc.left, rc.top, width, height);
// 設(shè)置投影矩陣glMatrixMode(GL_PROJECTION);glLoadIdentity();
// 投影變換(透視投影)
float ratio = (float) width / height;glFrustumf(-ratio, ratio, -1, 1, 2, 10);//glOrthox(FixedFromInt(-50),F(xiàn)ixedFromInt(50), FixedFromInt(-50), FixedFromInt(50), FixedFromInt(-50), FixedFromInt(50));
// 選擇模型觀察矩陣glMatrixMode(GL_MODELVIEW);// 重置模型觀察矩陣glLoadIdentity();
return TRUE;}
void CreateSurface()
{ glDisable(GL_DITHER);
// 告訴系統(tǒng)對透視進(jìn)行修正glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_FASTEST);// 黑色背景glClearColor(0, 0, 0, 0);
// 啟用陰影平滑glShadeModel(GL_SMOOTH);
// 設(shè)置深度緩存glClearDepthf(1.0f);// 啟用深度測試glEnable(GL_DEPTH_TEST);// 所作深度測試的類型glDepthFunc(GL_LEQUAL);
// 啟用2D紋理glEnable(GL_TEXTURE_2D);// 加載紋理LoadTexture(_T("\NAND2\OpenGlRes\1.png"),&texture[0]);LoadTexture(_T("\NAND2\OpenGlRes\1.png"),&texture[1]);LoadTexture(_T("\NAND2\OpenGlRes\1.png"),&texture[2]);LoadTexture(_T("\NAND2\OpenGlRes\1.png"),&texture[3]);LoadTexture(_T("\NAND2\OpenGlRes\1.png"),&texture[4]);LoadTexture(_T("\NAND2\OpenGlRes\1.png"),&texture[5]);}
void Render()
{ static float rotation = 0;// 清除屏幕和深度緩存glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glMatrixMode(GL_MODELVIEW);// 重置當(dāng)前的模型觀察矩陣glLoadIdentity();
// 坐標(biāo)變換glTranslatef(0.0f, 0.0f, -5.0f);
// 設(shè)置旋轉(zhuǎn)glRotatef(rotation++, 0.0f, 1.0f, 0.0f);glRotatef(rotation++, 1.0f, 0.0f, 0.0f);
glEnableClientState(GL_VERTEX_ARRAY);glEnableClientState(GL_TEXTURE_COORD_ARRAY);
glVertexPointer(3, GL_SHORT, 0, vertices);glTexCoordPointer(2, GL_SHORT, 0, texCoords);
// 繪制立方體并綁定紋理glBindTexture(GL_TEXTURE_2D, texture[0]);glDrawElements(GL_TRIANGLE_STRIP, 4, GL_UNSIGNED_BYTE, indices1);glBindTexture(GL_TEXTURE_2D, texture[1]);glDrawElements(GL_TRIANGLE_STRIP, 8, GL_UNSIGNED_BYTE, indices2);glBindTexture(GL_TEXTURE_2D, texture[2]);glDrawElements(GL_TRIANGLE_STRIP, 12, GL_UNSIGNED_BYTE, indices3);glBindTexture(GL_TEXTURE_2D, texture[3]);glDrawElements(GL_TRIANGLE_STRIP, 16, GL_UNSIGNED_BYTE, indices4);glBindTexture(GL_TEXTURE_2D, texture[4]);glDrawElements(GL_TRIANGLE_STRIP, 20, GL_UNSIGNED_BYTE, indices5);glBindTexture(GL_TEXTURE_2D, texture[5]);glDrawElements(GL_TRIANGLE_STRIP, 24, GL_UNSIGNED_BYTE, indices6);[!--empirenews.page--]
glDisableClientState(GL_TEXTURE_COORD_ARRAY);glDisableClientState(GL_VERTEX_ARRAY);
eglSwapBuffers(glesDisplay, glesSurface);}
void Clean()
{ if(glesDisplay)
{ eglMakeCurrent(glesDisplay, NULL, NULL, NULL);if(glesContext) eglDestroyContext(glesDisplay, glesContext);if(glesSurface) eglDestroySurface(glesDisplay, glesSurface);eglTerminate(glesDisplay);}
BOOL LoadTexture(LPCTSTR lpFileName,GLuint *id)
{ if(!g_Image.Load(lpFileName))
return FALSE;
// 創(chuàng)建紋理glGenTextures(1, id);// 綁定紋理glBindTexture(GL_TEXTURE_2D, *id);glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, g_Image.Width(), g_Image.Height(), 0, GL_RGB, GL_UNSIGNED_BYTE, g_Image.GetBmpImage());
g_Image.Free();
return TRUE;}
以下實現(xiàn)了一個文件加載類,用以將外部圖片資源轉(zhuǎn)化成繪制紋理時所需的位圖數(shù)據(jù)。參考代碼如下:
view plain /******************************************************************** filename: CImgLoader.h created: 2011-01-05 author: firehood
purpose: 文件加載類,將外部圖片資源轉(zhuǎn)化成繪制紋理時所需的位圖數(shù)據(jù)圖片格式支持bmp、png、jpg. *********************************************************************/ #pragma once
class CImgLoader { public:CImgLoader(void);~CImgLoader(void);public:// 加載圖片資源BOOL Load(LPCTSTR lpFileName);// 獲取位圖數(shù)據(jù)unsigned char* GetBmpImage(void);// 釋放圖片資源void Free();// 獲取圖像寬度int Width();// 獲取圖像高度int Height();private:int m_Width; // 圖像寬度int m_Height; // 圖像高度unsigned char *m_pImage; // 指向圖像數(shù)據(jù)的指針};
view plain /******************************************************************** filename: CImgLoader.cpp created: 2011-01-05 author: firehood
purpose: 文件加載類,將外部圖片資源轉(zhuǎn)化成繪制紋理時所需的位圖數(shù)據(jù)圖片格式支持bmp、png、jpg. *********************************************************************/
#include "StdAfx.h" #include "ImgLoader.h" // IImage Includer #include
CImgLoader::CImgLoader(void)
{ m_pImage = NULL;m_Width = 0;m_Height = 0;}
CImgLoader::~CImgLoader(void)
{ }
// 加載圖片資源BOOL CImgLoader::Load(LPCTSTR lpFileName)
{ IImagingFactory *pImgFactory = NULL;IImage *pImage = NULL;IBitmapImage *pBmpImg = NULL;// CoInitializeEx(NULL, COINIT_MULTITHREADED);if (!SUCCEEDED(CoCreateInstance(CLSID_ImagingFactory, NULL, CLSCTX_INPROC_SERVER, IID_IImagingFactory, (void **) &pImgFactory)))
return FALSE;if (!SUCCEEDED(pImgFactory->CreateImageFromFile(lpFileName, &pImage)))
return FALSE;// 獲取圖像大小信息ImageInfo ImgInfo;pImage->GetImageInfo(&ImgInfo);
m_Width = ImgInfo.Width;m_Height = ImgInfo.Height;
if (FAILED(pImgFactory->CreateBitmapFromImage(pImage,m_Width,m_Height,PixelFormat24bppRGB,InterpolationHintDefault,&pBmpImg)))
{ return FALSE;} RECT rect = {0,0,m_Width,m_Height};BitmapData *BmpData = new BitmapData;
if (FAILED(pBmpImg->LockBits(&rect,ImageLockModeRead|ImageLockModeWrite,PixelFormat24bppRGB,BmpData)))
{ return FALSE;} int line = BmpData->Stride;LPBYTE lpData, lpLine, lpCurPixel;lpData = lpLine = (LPBYTE)BmpData->Scan0; // 獲取BMP位圖實際值的地址指針// 若為Bottom-Up(從下到上)的位圖,則指向buffer的結(jié)尾// 若為Top-Down(從上到下)的位圖,則指向buffer的開頭// int nBytesPP = nBPP >> 3; // 左移三位即除以8,獲取圖像每像素字節(jié)數(shù)m_pImage = new unsigned char[m_Width * m_Height * 3];memset(m_pImage, 0, m_Width * m_Height * 3);if(m_pImage == NULL)
return FALSE;if (line>0)
{ int pos = m_Width * m_Height * 3-1;for(int i = 0; i
{ return FALSE;} delete BmpData;pBmpImg = NULL;pImage->Release();pImgFactory->Release();return TRUE;}
// 獲取圖片數(shù)據(jù)unsigned char* CImgLoader::GetBmpImage(void)
{ return m_pImage;}
// 獲取圖像寬度int CImgLoader::Width()
{ return m_Width;}
// 獲取圖像高度int CImgLoader::Height()
{ return m_Height;}
// 釋放圖片資源void CImgLoader::Free()
{ if(m_pImage)
{ delete []m_pImage;m_pImage = NULL;}