标签：opengl
WINCE系统上开发OpenGL程序需具备以下条件：
1. 处理器的支持，嵌入式处理器需支持3D加速渲染（测试使用的是Telichips 8901）；
2. WINCE内核的支持，定制内核时需添加OpenGL ES相关组件。
以下是具体的参考代码：
[cpp] view plain copy
/********************************************************************
filename: WinceOpenGLDemo.cpp
created: 2011-01-05
author: firehood
purpose: 利用OpenGL ES实现了绘制立方体和纹理效果
*********************************************************************/
// WinceOpenGLDemo.cpp : 定义应用程序的入口点。
//
#include "stdafx.h"
#include "WinceOpenGLDemo.h"
#include <windows.h>
#include <commctrl.h>
#include "ImgLoader.h"
// OpenGL ES Includes
#include <GLES/gl.h>
#include <GLES/glext.h>
#include <EGL/egl.h>
#include <EGL/eglext.h>
// OpenGL lib
#pragma comment(lib, "OpenGlLib\\libGLESv1_CM.lib")
#pragma comment(lib, "OpenGlLib\\libEGL.lib")
// 全局变量:
HINSTANCE g_hInst; // 当前实例
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};
// 立方体定点坐标
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
};
// 各个面纹理坐标
GLshort texCoords[] = {
0,0,1,0,1,1,0,1,
0,0,1,0,1,1,0,1,
0,0,1,0,1,1,0,1,
0,0,1,0,1,1,0,1,
0,0,1,0,1,1,0,1,
0,0,1,0,1,1,0,1,
};
// 三角形索引数据
GLbyte indices1[] = {
0,1,3,2,
0,0,0,0,
0,0,0,0,
0,0,0,0,
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,
0,0,0,0,
0,0,0,0
};
GLbyte indices3[] = {
0,0,0,0,
0,0,0,0,
8,9,11,10,
0,0,0,0,
0,0,0,0,
0,0,0,0
};
GLbyte indices4[] = {
0,0,0,0,
0,0,0,0,
0,0,0,0,
12,13,15,14,
0,0,0,0,
0,0,0,0
};
GLbyte indices5[] = {
0,0,0,0,
0,0,0,0,
0,0,0,0,
0,0,0,0,
16,17,19,18,
0,0,0,0
};
GLbyte indices6[] = {
0,0,0,0,
0,0,0,0,
0,0,0,0,
0,0,0,0,
0,0,0,0,
20,21,23,22
};
// 此代码模块中包含的函数的前向声明:
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;
// 执行应用程序初始化:
if (!InitInstance(hInstance, nCmdShow))
{
return FALSE;
}
BOOL done = FALSE;
// 主消息循环:
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;
}
//
// 函数: MyRegisterClass()
//
// 目的: 注册窗口类。
//
// 注释:
//
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);
}
//
// 函数: InitInstance(HINSTANCE, int)
//
// 目的: 保存实例句柄并创建主窗口
//
// 注释:
//
// 在此函数中，我们在全局变量中保存实例句柄并
// 创建和显示主程序窗口。
//
BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
{
HWND hWnd;
g_hInst = hInstance; // 将实例句柄存储在全局变量中
if (!MyRegisterClass(hInstance, szAppName))
{
return FALSE;
}
hWnd = CreateWindow(
szAppName,
szAppName,
WS_VISIBLE,
0,
0,
::GetSystemMetrics(SM_CXSCREEN),
::GetSystemMetrics(SM_CYSCREEN),
NULL,
NULL,
hInstance,
NULL);
if (!hWnd)
{
return FALSE;
}
if(!InitOGLES(hWnd))
{
printf("InitOGLES failed\n");
return FALSE;
}
CreateSurface();
ShowWindow(hWnd, SW_SHOW);
UpdateWindow(hWnd);
return TRUE;
}
//
// 函数: WndProc(HWND, UINT, WPARAM, LPARAM)
//
// 目的: 处理主窗口的消息。
//
// WM_COMMAND - 处理应用程序菜单
// WM_PAINT - 绘制主窗口
// WM_DESTROY - 发送退出消息并返回
//
//
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT ps;
HDC hdc;
switch (message)
{
case WM_CREATE:
break;
case WM_PAINT:
hdc = BeginPaint(hWnd, &ps);
// TODO: 在此添加任意绘图代码...
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%04x\n",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;
// 设置OpenGL场景的大小
glViewport(rc.left, rc.top, width, height);
// 设置投影矩阵
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
// 投影变换（透视投影）
float ratio = (float) width / height;
glFrustumf(-ratio, ratio, -1, 1, 2, 10);
//glOrthox(FixedFromInt(-50),FixedFromInt(50), FixedFromInt(-50), FixedFromInt(50), FixedFromInt(-50), FixedFromInt(50));
// 选择模型观察矩阵
glMatrixMode(GL_MODELVIEW);
// 重置模型观察矩阵
glLoadIdentity();
return TRUE;
}
void CreateSurface()
{
glDisable(GL_DITHER);
// 告诉系统对透视进行修正
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_FASTEST);
// 黑色背景
glClearColor(0, 0, 0, 0);
// 启用阴影平滑
glShadeModel(GL_SMOOTH);
// 设置深度缓存
glClearDepthf(1.0f);
// 启用深度测试
glEnable(GL_DEPTH_TEST);
// 所作深度测试的类型
glDepthFunc(GL_LEQUAL);
// 启用2D纹理
glEnable(GL_TEXTURE_2D);
// 加载纹理
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;
// 清除屏幕和深度缓存
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glMatrixMode(GL_MODELVIEW);
// 重置当前的模型观察矩阵
glLoadIdentity();
// 坐标变换
glTranslatef(0.0f, 0.0f, -5.0f);
// 设置旋转
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);
// 绘制立方体并绑定纹理
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);
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;
// 创建纹理
glGenTextures(1, id);
// 绑定纹理
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;
}
以下实现了一个文件加载类，用以将外部图片资源转化成绘制纹理时所需的位图数据。参考代码如下：
[cpp] view plain copy
/********************************************************************
filename: CImgLoader.h
created: 2011-01-05
author: firehood
purpose: 文件加载类，将外部图片资源转化成绘制纹理时所需的位图数据
图片格式支持bmp、png、jpg.
*********************************************************************/
#pragma once
class CImgLoader
{
public:
CImgLoader(void);
~CImgLoader(void);
public:
// 加载图片资源
BOOL Load(LPCTSTR lpFileName);
// 获取位图数据
unsigned char* GetBmpImage(void);
// 释放图片资源
void Free();
// 获取图像宽度
int Width();
// 获取图像高度
int Height();
private:
int m_Width; // 图像宽度
int m_Height; // 图像高度
unsigned char *m_pImage; // 指向图像数据的指针
};
本文出自 “11486263” 博客，请务必保留此出处http://11496263.blog.51cto.com/11486263/1828360
标签：opengl
原文地址：http://11496263.blog.51cto.com/11486263/1828360
