烟花OpenGL初步实现demo

在NeHe程序框架基础上初步实现了这个烟花的demo。

烟花的弹片生存期由life和fade两个值决定。

烟花的弹片速度由speed和a两个值决定。

生命值和速度值变换在每次循环中加减运算实现，所以有必要添加一个参数来根据每台电脑的运算速度加以调整优化。

实现代码如下。所需BMP图片在这里。

//vs2008 & windows7
#include<windows.h>
#include<tchar.h>
#include <gl\gl.h>
#include <gl\glu.h>
#pragma comment(lib,"opengl32.lib")
#pragma comment(lib,"glu32.lib")

#define   MAX_NUM_PARTICLES 20     //粒子数
#define   MAX_NUM_SHELLS 40     //弹片数

HGLRC hRC=NULL;            //OpenGL图形操作描述表
HDC hDC=NULL;                 //设备描述表
HWND  hWnd=NULL;           //窗口句柄
HINSTANCE hInstance;        //应用程序实例

bool keys[256];                  //键盘按键参数阵列
bool active=TRUE;             //窗口是否活动
bool fullscreen=TRUE;       //是否全屏

bool rainbow=false;      //彩虹模式，改变颜色
bool sp;                         //空格键击键标志
bool rp;                          //回车键击键标志

float slowdown=1.0f;                                                //粒子减速控制
float zoom=-55.0f;                          //视野变焦

GLuint loop,loop2,color,delay;             //循环参数、当前颜色、延迟
GLuint texture[1];                     //粒子贴图

float shell_life=5.0f;                    //弹片高度
float shell_fade=0.05f;
float shell_life1=4.0f;                    //弹片高度
float shell_fade1=0.05f;
float sxspeed=0.0f;                    //弹片速度
float szspeed=0.0f;
float syspeed=850.0f;
float shell_yg=-4.8f;

float particle_life=2.0f;        //粒子高度
float particle_fade;
float xspeed;                                 //粒子速度
float yspeed;
float zspeed;
float particle_yg=-2.8f;

float par_times=2.0f;                //速度倍数
float par_times1=10.0f;

float x,y,z;
float x1,y1,z1;

typedef struct
{
    bool active;                         //状态，生存or湮灭
    float life;                                 //粒子生命
    float fade;                             //衰减速度
    float r,g,b;                                //颜色
    float x,y,z;                            //当前位置
    float xd,yd,zd;                    //速度
    float xg,yg,zg;                    //加速度 a=1-p[空气]/p[物质]
}particle;                    //粒子结构

typedef struct
{
    bool active;                         //状态，生存or湮灭
    float life;                                 //粒子生命
    float fade;                             //衰减速度
    unsigned int status;    //阶段
    float x,y,z;                            //当前位置
    float xd,yd,zd;                    //速度
    float xg,yg,zg;                    //加速度 a=1-p[空气]/p[物质]
    particle particles[MAX_NUM_PARTICLES];     //颗粒
}shell;            //弹片

shell  shells[MAX_NUM_SHELLS];    //弹体

static GLfloat colors[4][3]=                // 颜色值
{
    {1.0f,1.0f,1.0f},{1.0f,0.0f,0.0f},{1.0f,1.0f,0.0f},{1.0f,0.0f,1.0f}
};
//
LRESULT    CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);   //消息处理函数
bool NeHeLoadBitmap(LPTSTR szFileName, GLuint *texid);    //贴图图像载入
GLvoid ReSizeGLScene(GLsizei width, GLsizei height);   //重新绘制窗口
int InitGL(GLvoid);     //初始化OpenGL
int DrawGLScene(GLvoid);      //画图
GLvoid KillGLWindow(GLvoid)    ;                //关闭窗口
//
bool NeHeLoadBitmap(LPTSTR szFileName, GLuint *texid)                    //从一个bmp文件创建贴图
{
    HBITMAP hBMP;                                            //bmp文件句柄
    BITMAP    BMP;                                                        // Bitmap数据结构
    glGenTextures(1, texid);                    // 创建贴图
    hBMP=(HBITMAP)LoadImage(GetModuleHandle(NULL), szFileName, IMAGE_BITMAP, 0, 0, LR_CREATEDIBSECTION | LR_LOADFROMFILE );
    if (!hBMP)
        return FALSE;
    GetObject(hBMP, sizeof(BMP), &BMP);                    //获得目标
    glPixelStorei(GL_UNPACK_ALIGNMENT, 4);            // Pixel Storage Mode (Word Alignment / 4 Bytes)
    //创建贴图
    glBindTexture(GL_TEXTURE_2D, *texid);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexImage2D(GL_TEXTURE_2D, 0, 3, BMP.bmWidth, BMP.bmHeight, 0, GL_BGR_EXT, GL_UNSIGNED_BYTE, BMP.bmBits);
    DeleteObject(hBMP);
    return TRUE;
}//end of NeHeLoadBitmap

GLvoid ReSizeGLScene(GLsizei width, GLsizei height)                //重画窗口
{
    if (height==0)    height=1;
    glViewport(0, 0, width, height);                    //重置当前窗口
    glMatrixMode(GL_PROJECTION);                        // Select The Projection Matrix
    glLoadIdentity();                            // Reset The Projection Matrix
    gluPerspective(45.0f,(GLfloat)width/(GLfloat)height,0.1f,200.0f);     //视图
    glMatrixMode(GL_MODELVIEW);                        // Select The Modelview Matrix
    glLoadIdentity();                            // Reset The Modelview Matrix
}//end of ReSizeGLScene

int InitGL(GLvoid)                                //初始化gl
{
    if (!NeHeLoadBitmap(_T("Data\\Particle.bmp"), &texture[0]))    {return FALSE;    }//载入贴图
    glShadeModel(GL_SMOOTH);                        // Enables Smooth Shading
    glClearColor(0.0f,0.0f,0.0f,0.0f);                    // Black Background
    glClearDepth(1.0f);                            // Depth Buffer Setup
    glDisable(GL_DEPTH_TEST);                        // Disables Depth Testing
    glEnable(GL_BLEND);                            // Enable Blending
    glBlendFunc(GL_SRC_ALPHA,GL_ONE);                    // Type Of Blending To Perform
    glHint(GL_PERSPECTIVE_CORRECTION_HINT,GL_NICEST);            // Really Nice Perspective Calculations
    glHint(GL_POINT_SMOOTH_HINT,GL_NICEST);                    // Really Nice Point Smoothing
    glEnable(GL_TEXTURE_2D);                        // Enable Texture Mapping
    glBindTexture(GL_TEXTURE_2D,texture[0]);                // Select Our Texture

    for(loop2=0;loop2<MAX_NUM_SHELLS;loop2++)    
    {
        shells[loop2].active=true;                    
        shells[loop2].status=0;                        //0-上升阶段
        shells[loop2].life=shell_life1;
        //    shells[loop2].fade=float(rand()%100)/1000.0f+0.003f;
        shells[loop2].fade=shell_fade1;
        shells[loop2].xd=float((rand()%50)-25.0f)*par_times1;
        shells[loop2].yd=float((rand()%50)-25.0f)*par_times1;
        shells[loop2].zd=float((rand()%50)-25.0f)*par_times1;
        shells[loop2].xg=0.0f;
        shells[loop2].yg=shell_yg;
        shells[loop2].zg=0.0f;
        for (loop=0;loop<MAX_NUM_PARTICLES;loop++)                    // 初始化所有贴图
        {
            shells[loop2].particles[loop].active=true;                    // 使所有粒子为活动
            shells[loop2].particles[loop].life=particle_life;                    // 所有粒子生命值
            shells[loop2].particles[loop].fade=float(rand()%100)/100.0f+0.03f;        // 随机生命递减速度
            shells[loop2].particles[loop].r=colors[color][0];        //颜色
            shells[loop2].particles[loop].g=colors[color][1];        
            shells[loop2].particles[loop].b=colors[color][2];        
            shells[loop2].particles[loop].xd=float((rand()%50)-25.0f)*par_times;        //随机速度
            shells[loop2].particles[loop].yd=float((rand()%50)-25.0f)*par_times;    
            shells[loop2].particles[loop].zd=float((rand()%50)-25.0f)*par_times;
            shells[loop2].particles[loop].xg=0.0f;                                        //加速度
            shells[loop2].particles[loop].yg=particle_yg;
            shells[loop2].particles[loop].zg=0.0f;
        }
    }
    shells[0].life=shell_life;
    shells[0].fade=shell_fade;
    return TRUE;
}//end of InitGL

int DrawGLScene(GLvoid)                                //画图
{
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);            // Clear The Screen And The Depth Buffer
    glLoadIdentity();                            // Reset The Current Modelview Matrix

    switch(shells[0].status)
    {
    case 0:                                //上升阶段
        {
            if(shells[0].life==shell_life)
            {
                shells[0].x=0.0f;
                shells[0].y=-30.0f;
                shells[0].z=zoom;
                shells[0].xd=sxspeed;            //获得初始速度
                shells[0].yd=syspeed;
                shells[0].zd=szspeed;
                //
                for(loop=0;loop<MAX_NUM_PARTICLES;loop++)
                {
                    shells[0].particles[loop].x=shells[0].x;
                    shells[0].particles[loop].y=shells[0].y;
                    shells[0].particles[loop].z=shells[0].z;
                }
            }//if life        
            shells[0].x+=shells[0].xd/(slowdown*1000);            //新位置
            shells[0].y+=shells[0].yd/(slowdown*1000);
            shells[0].z+=shells[0].zd/(slowdown*1000);
            shells[0].xd+=shells[0].xg;                //速度增量
            shells[0].yd+=shells[0].yg;
            shells[0].zd+=shells[0].zg;            
            shells[0].life-=shells[0].fade;                //生命递减
            if(shells[0].life<0.0f)
            {
                shells[0].status=1;     //转到下一个阶段
                shells[0].active=false;
                x1=shells[0].x;
                y1=shells[0].y;
                z1=shells[0].z;
                break;
            }    

            for(loop=0;loop<MAX_NUM_PARTICLES;loop++)
            {
                if(shells[0].particles[loop].active)
                {
                    shells[0].particles[loop].x+=shells[0].particles[loop].xd/(slowdown*1000);                //位置改变
                    shells[0].particles[loop].y+=shells[0].particles[loop].yd/(slowdown*1000);
                    shells[0].particles[loop].z+=shells[0].particles[loop].zd/(slowdown*1000);
                    shells[0].particles[loop].xd+=shells[0].particles[loop].xg;                                    //速度增量
                    shells[0].particles[loop].yd+=shells[0].particles[loop].yg;
                    shells[0].particles[loop].zd+=shells[0].particles[loop].zg;
                    shells[0].particles[loop].life-=shells[0].particles[loop].fade;                            //生命减少

                    x=shells[0].particles[loop].x;                                //获得位置坐标
                    y=shells[0].particles[loop].y;
                    z=shells[0].particles[loop].z+zoom;
                    glColor4f(shells[0].particles[loop].r,shells[0].particles[loop].g,shells[0].particles[loop].b,shells[0].particles[loop].life);            //颜色
                    glBegin(GL_TRIANGLE_STRIP);                                                                            //两个三角画一个矩形
                    glTexCoord2d(1,1);glVertex3f(x+0.5f,y+0.5f,z);
                    glTexCoord2d(0,1);glVertex3f(x-0.5f,y+0.5f,z);
                    glTexCoord2d(1,0); glVertex3f(x+0.5f,y-0.5f,z); 
                    glTexCoord2d(0,0); glVertex3f(x-0.5f,y-0.5f,z); 
                    glEnd();

                    if(shells[0].particles[loop].life<0.0f)                                //湮灭
                    {
                        shells[0].particles[loop].life=particle_life;        //获得新生
                        shells[0].particles[loop].fade=float(rand()%100)/100.0f+0.03f;    //生命递减速度
                        shells[0].particles[loop].x=shells[0].x;                            //新生粒子位置与弹片位置相同
                        shells[0].particles[loop].y=shells[0].y;
                        shells[0].particles[loop].z=shells[0].z;
                        shells[0].particles[loop].xd=xspeed+float((rand()%50)-25.0f)*par_times;                    //初始速度
                        shells[0].particles[loop].yd=yspeed+float((rand()%50)-25.0f)*par_times;
                        shells[0].particles[loop].zd=zspeed+float((rand()%50)-25.0f)*par_times;
                        shells[0].particles[loop].r=colors[color][0];                                //粒子颜色，用参数color改变
                        shells[0].particles[loop].g=colors[color][1];        
                        shells[0].particles[loop].b=colors[color][2];        
                    }//end of if life

                }//end of if active
            }//end of for  loop
            break;
        }//end of case 0:
    case 1:
        {
            if(shells[0].active==false)
            {
                shells[0].active=true;
                for(loop2=1;loop2<MAX_NUM_SHELLS;loop2++)
                {
                    shells[loop2].x=x1;
                    shells[loop2].y=y1;
                    shells[loop2].z=z1;
                }
            }//if !
            for(loop2=1;loop2<MAX_NUM_SHELLS;loop2++)
            {
                //                if(shells[loop2].life>0.0f)
                //                {
                for(loop=0;loop<MAX_NUM_PARTICLES;loop++)
                {
                    if(shells[loop2].life==shell_life1)
                    {
                        shells[loop2].particles[loop].x=shells[loop2].x;
                        shells[loop2].particles[loop].y=shells[loop2].y;
                        shells[loop2].particles[loop].z=shells[loop2].z;
                    }
                    shells[loop2].particles[loop].x+=shells[loop2].particles[loop].xd/(slowdown*1000);                //位置改变
                    shells[loop2].particles[loop].y+=shells[loop2].particles[loop].yd/(slowdown*1000);
                    shells[loop2].particles[loop].z+=shells[loop2].particles[loop].zd/(slowdown*1000);
                    shells[loop2].particles[loop].xd+=shells[loop2].particles[loop].xg;                                    //速度增量
                    shells[loop2].particles[loop].yd+=shells[loop2].particles[loop].yg;
                    shells[loop2].particles[loop].zd+=shells[loop2].particles[loop].zg;
                    shells[loop2].particles[loop].life-=shells[loop2].particles[loop].fade;                            //生命减少

                    x=shells[loop2].particles[loop].x;                                //获得位置坐标
                    y=shells[loop2].particles[loop].y;
                    z=shells[loop2].particles[loop].z+zoom;
                    glColor4f(shells[loop2].particles[loop].r,shells[loop2].particles[loop].g,shells[loop2].particles[loop].b,shells[loop2].particles[loop].life);            //颜色
                    glBegin(GL_TRIANGLE_STRIP);                                                                            //两个三角画一个矩形
                    glTexCoord2d(1,1);glVertex3f(x+0.5f,y+0.5f,z);
                    glTexCoord2d(0,1);glVertex3f(x-0.5f,y+0.5f,z);
                    glTexCoord2d(1,0); glVertex3f(x+0.5f,y-0.5f,z); 
                    glTexCoord2d(0,0); glVertex3f(x-0.5f,y-0.5f,z); 
                    glEnd();

                    if(shells[loop2].particles[loop].life<0.0f)                                //湮灭
                    {
                        shells[loop2].particles[loop].life=particle_life;        //获得新生
                        shells[loop2].particles[loop].fade=float(rand()%100)/100.0f+0.03f;    //生命递减速度
                        shells[loop2].particles[loop].x=shells[loop2].x;
                        shells[loop2].particles[loop].y=shells[loop2].y;
                        shells[loop2].particles[loop].z=shells[loop2].z;
                        shells[loop2].particles[loop].xd=xspeed+float((rand()%50)-25.0f)*par_times;                    //初始速度
                        shells[loop2].particles[loop].yd=yspeed+float((rand()%50)-25.0f)*par_times;
                        shells[loop2].particles[loop].zd=zspeed+float((rand()%50)-25.0f)*par_times;
                        shells[loop2].particles[loop].r=colors[color][0];                                //粒子颜色，用参数color改变
                        shells[loop2].particles[loop].g=colors[color][1];        
                        shells[loop2].particles[loop].b=colors[color][2];        
                    }
                }//for loop
                //                    }//if life
                shells[loop2].x+=shells[loop2].xd/(slowdown*1000);            //新位置
                shells[loop2].y+=shells[loop2].yd/(slowdown*1000);
                shells[loop2].z+=shells[loop2].zd/(slowdown*1000);
                shells[loop2].xd+=shells[loop2].xg;                //速度增量
                shells[loop2].yd+=shells[loop2].yg;
                shells[loop2].zd+=shells[loop2].zg;
                shells[loop2].life-=shells[loop2].fade;                //生命递减
                if(shells[1].life<0.0f){shells[1].status=1;}
            }//for loop2
            break;
        }//end of case 1:
    default:
        break;
    }//end of switch

    if (keys[VK_TAB]||shells[1].status==1)                        //TAB发射一颗新烟花弹
    {
        shells[0].life=shell_life;
        shells[0].status=0;
        for(loop2=0;loop2<MAX_NUM_SHELLS;loop2++)    
        {
            shells[loop2].active=true;                    
            shells[loop2].status=0;                        //0-上升阶段
            shells[loop2].life=shell_life1;
            //    shells[loop2].fade=float(rand()%100)/1000.0f+0.003f;
            shells[loop2].fade=shell_fade1;
            shells[loop2].xd=float((rand()%50)-25.0f)*par_times1;
            shells[loop2].yd=float((rand()%50)-25.0f)*par_times1;
            shells[loop2].zd=float((rand()%50)-25.0f)*par_times1;
            shells[loop2].xg=0.0f;
            shells[loop2].yg=shell_yg;
            shells[loop2].zg=0.0f;
            for (loop=0;loop<MAX_NUM_PARTICLES;loop++)                    // 初始化所有贴图
            {
                shells[loop2].particles[loop].active=true;                    // 使所有粒子为活动
                shells[loop2].particles[loop].life=particle_life;                    // 所有粒子生命值
                shells[loop2].particles[loop].fade=float(rand()%100)/100.0f+0.03f;        // 随机生命递减速度
                shells[loop2].particles[loop].r=colors[color][0];        //颜色
                shells[loop2].particles[loop].g=colors[color][1];        
                shells[loop2].particles[loop].b=colors[color][2];        
                shells[loop2].particles[loop].xd=float((rand()%50)-25.0f)*par_times;        //随机速度
                shells[loop2].particles[loop].yd=float((rand()%50)-25.0f)*par_times;    
                shells[loop2].particles[loop].zd=float((rand()%50)-25.0f)*par_times;
                shells[loop2].particles[loop].xg=0.0f;                                        //加速度
                shells[loop2].particles[loop].yg=particle_yg;
                shells[loop2].particles[loop].zg=0.0f;
            }
        }
        shells[0].life=shell_life;
        shells[0].fade=shell_fade;
    }//if

    return TRUE;    
}//end of DrawGLScene

<完>