opengl制作的一个简单的粒子系统

#include "stdafx.h" #include <stdlib.h> #include <GL\glut.h> #include <gl\glaux.h> #define PARTICLES_NUMBER 1000 // 粒子数量 float slowdown=2.0f; // 用来减小例子速度 float zoom=-40.0f; GLuint loop; // 用来遍历所有粒子 GLuint col; // 颜色索引 GLuint texture[1]; // 存储粒子的Texture typedef struct // 粒子结构 { bool active; // 是否活动 float life; // 生存时间 float fade; // 生命减少速率 float r; // 颜色值Red分量 float g; // Green float b; // Blue float x; // 粒子X坐标值 float y; // Y float z; // Z float xi; // X方向速度 float yi; // Y float zi; // Z float xg; // X加速度 float yg; // Y float zg; // Z } particles; // Particles Structure particles particle[PARTICLES_NUMBER]; // Particle Array (Room For Particle Info) static GLfloat colors[12][3]= // Rainbow Of Colors { {1.0f,0.5f,0.5f},{1.0f,0.75f,0.5f},{1.0f,1.0f,0.5f},{0.75f,1.0f,0.5f}, {0.5f,1.0f,0.5f},{0.5f,1.0f,0.75f},{0.5f,1.0f,1.0f},{0.5f,0.75f,1.0f}, {0.5f,0.5f,1.0f},{0.75f,0.5f,1.0f},{1.0f,0.5f,1.0f},{1.0f,0.5f,0.75f} }; AUX_RGBImageRec *LoadBMP(char *Filename) // 载入图片 { FILE *File=NULL; if (!Filename) { return NULL; } File=fopen(Filename,"r"); if (File) { fclose(File); return auxDIBImageLoad(Filename); } return NULL; } void LoadGLTextures(void) // 载入Texture { AUX_RGBImageRec *TextureImage[1]; memset(TextureImage,0,sizeof(void *)*1); if (TextureImage[0]=LoadBMP("Data/Star.bmp")) { glGenTextures(1, texture); // Create One Texture glBindTexture(GL_TEXTURE_2D, texture[0]); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR); glTexImage2D(GL_TEXTURE_2D, 0, 3, TextureImage[0]->sizeX, TextureImage[0]->sizeY, 0, GL_RGB, GL_UNSIGNED_BYTE, TextureImage[0]->data); } } void ReSizeGLScene(GLsizei width, GLsizei height) // Resize And Initialize The GL Window { if (height==0) // Prevent A Divide By Zero By { height=1; // Making Height Equal One } glViewport(0,0,width,height); // Reset The Current Viewport glMatrixMode(GL_PROJECTION); // Select The Projection Matrix glLoadIdentity(); // Reset The Projection Matrix // Calculate The Aspect Ratio Of The Window gluPerspective(45.0f,(GLfloat)width/(GLfloat)height,0.1f,200.0f); glMatrixMode(GL_MODELVIEW); // Select The Modelview Matrix glLoadIdentity(); // Reset The Modelview Matrix } void InitGL(void) { LoadGLTextures(); glShadeModel(GL_SMOOTH); // Enable Smooth Shading glClearColor(0.0f,0.0f,0.0f,0.0f); // Black Background glClearDepth(1.0f); // Depth Buffer Setup glDisable(GL_DEPTH_TEST); // Disable 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 (loop=0;loop<PARTICLES_NUMBER;loop++) // 初始化粒子 { particle[loop].active=true; particle[loop].life=1.0f; // 生存周期 particle[loop].fade=float(rand()%100)/1000.0f+0.003f; particle[loop].r=colors[loop*(12/PARTICLES_NUMBER)][0]; particle[loop].g=colors[loop*(12/PARTICLES_NUMBER)][1]; particle[loop].b=colors[loop*(12/PARTICLES_NUMBER)][2]; particle[loop].xi=float((rand()%50)-25.0f)*10.0f; particle[loop].yi=float((rand()%50)-25.0f)*10.0f; particle[loop].zi=float((rand()%50)-25.0f)*10.0f; particle[loop].xg=0.0f; particle[loop].yg=-0.7f; //y方向的加速度（重力模型） particle[loop].zg=0.0f; } } void DrawGLScene(void) { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glLoadIdentity(); for (loop=0;loop<PARTICLES_NUMBER;loop++) //遍历每一个粒子 { if (particle[loop].active) { float x=particle[loop].x; float y=particle[loop].y; float z=particle[loop].z+zoom; col++; //为每一个粒子赋不同的颜色值 if(col>11) col=0; glColor4f(particle[loop].r,particle[loop].g,particle[loop].b,particle[loop].life); glBegin(GL_TRIANGLE_STRIP); // Build Quad From A Triangle Strip glTexCoord2d(1,1); glVertex3f(x+0.5f,y+0.5f,z); // Top Right glTexCoord2d(0,1); glVertex3f(x-0.5f,y+0.5f,z); // Top Left glTexCoord2d(1,0); glVertex3f(x+0.5f,y-0.5f,z); // Bottom Right glTexCoord2d(0,0); glVertex3f(x-0.5f,y-0.5f,z); // Bottom Left glEnd(); particle[loop].x+=particle[loop].xi/(slowdown*500);//改变粒子在x轴上的位置 particle[loop].y+=particle[loop].yi/(slowdown*100);//Y particle[loop].z+=particle[loop].zi/(slowdown*500);//Z //particle[loop].xi+=particle[loop].xg; //X方向速度值 particle[loop].yi+=particle[loop].yg*(1.0f-particle[loop].life); //Y方向的速度值 //particle[loop].zi+=particle[loop].zg; // Z方向的速度值 particle[loop].life-=particle[loop].fade; // 粒子的生存的剩余时间 if (particle[loop].life<0.0f) // 如果粒子的生命结束，则对其重新赋予新的生命 { particle[loop].life=1.0f; particle[loop].fade=float(rand()%100)/1000.0f+0.003f; particle[loop].x=0.0f; particle[loop].y=0.0f; particle[loop].z=0.0f; particle[loop].xi=float((rand()%50)-25.0f); particle[loop].yi=float((rand()%50)-25.0f); particle[loop].zi=float((rand()%50)-25.0f); particle[loop].yg=-0.7f; // Y方向上的加速度值（重力模型） if(particle[loop].yi<10) particle[loop].yi=20;//-particle[loop].yi;//保证粒子的初始方向向上 particle[loop].r=colors[col][0];//颜色值 particle[loop].g=colors[col][1]; particle[loop].b=colors[col][2]; } } } glutSwapBuffers(); } void TimerFunction(int value) { glutPostRedisplay(); glutTimerFunc(10,TimerFunction,1); } int main(int argc, _TCHAR* argv[]) { glutInitDisplayMode(GLUT_DOUBLE|GLUT_DEPTH|GLUT_RGB); glutInitWindowSize(800,800); glutInitWindowPosition(100,100); glutCreateWindow("Zhuang Xiaolong's Particles"); InitGL(); glutDisplayFunc(DrawGLScene); glutReshapeFunc(ReSizeGLScene); glutTimerFunc(10,TimerFunction,1); glutMainLoop(); return 0; }