[OpenGL]一个简单的地球月亮太阳运转模型

最新推荐文章于 2023-02-24 13:44:23 发布

iteye_19603

最新推荐文章于 2023-02-24 13:44:23 发布

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文章标签： javascript c/c++ ViewUI

本文展示了如何使用OpenGL技术动态绘制太阳、地球和月亮的3D模型，并实时更新它们的位置以模拟月相变化。

#include <GL/glut.h> 
#include <stdio.h> 
#include <time.h> 
 
// 太阳、地球和月亮 
// 假设每个月都是12天 
// 一年12个月，共是360天 
static int day = 200; // day的变化：从0到359 
 
double CalFrequency() 
{ 
    static int count; 
    static double save; 
    static clock_t last, current; 
    double timegap; 
 
    ++count; 
    if( count <= 50 ) 
        return save; 
    count = 0; 
    last = current; 
    current = clock(); 
    timegap = (current-last)/(double)CLK_TCK; 
    save = 50.0/timegap; 
    return save; 
} 
 
void myDisplay(void) 
{ 
    double FPS = CalFrequency(); 
    printf("FPS = %f\n", FPS); 
 
    glEnable(GL_DEPTH_TEST); 
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); 
 
    glMatrixMode(GL_PROJECTION); 
    glLoadIdentity(); 
    gluPerspective(75, 1, 1, 400000000); 
    glMatrixMode(GL_MODELVIEW); 
    glLoadIdentity(); 
    gluLookAt(0, -200000000, 200000000, 0, 0, 0, 0, 0, 1); 
 
    // 绘制红色的“太阳” 
    glColor3f(1.0f, 0.0f, 0.0f); 
    glutSolidSphere(69600000, 20, 20); 
    // 绘制蓝色的“地球” 
    glColor3f(0.0f, 0.0f, 1.0f); 
    glRotatef(day/360.0*360.0, 0.0f, 0.0f, -1.0f); 
    glTranslatef(150000000, 0.0f, 0.0f); 
    glutSolidSphere(15945000, 20, 20); 
    // 绘制黄色的“月亮” 
    glColor3f(1.0f, 1.0f, 0.0f); 
    glRotatef(day/30.0*360.0 - day/360.0*360.0, 0.0f, 0.0f, -1.0f); 
    glTranslatef(38000000, 0.0f, 0.0f); 
    glutSolidSphere(4345000, 20, 20); 
 
    glFlush(); 
    glutSwapBuffers(); 
} 
 
void myIdle(void) 
{ 
    ++day; 
    if( day >= 360 ) 
        day = 0; 
    myDisplay(); 
} 
 
int main(int argc, char *argv[]) 
{ 
    glutInit(&argc, argv); 
    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE); 
    glutInitWindowPosition(100, 100); 
    glutInitWindowSize(400, 400); 
    glutCreateWindow("太阳，地球和月亮"); 
    glutDisplayFunc(&myDisplay); 
    glutIdleFunc(&myIdle); 
    glutMainLoop(); 
    return 0; 
}