2.4.5 OpenGL程序实例分析
代码语言：javascript
复制#include <GL/glut.h>
float angle = 0.0f; //旋转角度
void Init()
{
GLfloat light_ambient[] = { 1.5,1.5,1.5,1.0 };//环境光分量RGB值
float lpos[4] = { 1.0,1.0,1,0 };//灯光坐标位置
glEnable(GL_DEPTH_TEST); //启用深度测试
glClearColor(0.0f, 0.0f, 0.0f, 1.0f); //背景为黑色
glLightfv(GL_LIGHT0, GL_POSITION, lpos);
glLightfv(GL_LIGHT0, GL_AMBIENT, light_ambient);
}
void Reshape(int w, int h)
{
if (0 == h) h = 1; //防止窗口高度太小而造成除零问题
float ratio = 1.0f* w / h;
glViewport(0, 0, w, h); //设置视区尺寸
glMatrixMode(GL_PROJECTION); //指定当前操作投影矩阵堆栈
glLoadIdentity(); //重置投影矩阵
gluPerspective(45.0f, ratio, 1.0f, 10.0f);//指定透视投影的观察空间
glMatrixMode(GL_MODELVIEW);
}
void myDisplay ()
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);//清除颜色和深度缓冲区
glColor3f(0.8f, 0.8f, 0.8f); //指定绘制立方体颜色
glMatrixMode(GL_MODELVIEW); //指定当前操作模型视图矩阵堆栈
glLoadIdentity(); //重置模型视图矩阵
glTranslatef(-1.0f, 0.0f, -5.0f); //将线框立方体沿x轴和z轴负向移动
glRotatef(angle, 0.0f, 1.0f, 0.0f);//线框立方体绕y轴旋转
glutWireCube(1);
glEnable(GL_LIGHTING); //启用光照
glEnable(GL_LIGHT0); //开启灯光0
glLoadIdentity();
glTranslatef(1.0f, 0.0f, -5.0f);
glRotatef(angle, 0.0f, 1.0f, 0.0f);
glutSolidCube(1);
glDisable(GL_LIGHTING); //关闭光照，因为线框立方体启用光照效果不好
angle = 0.01f;
glutSwapBuffers();
}
int main(int argc, char *argv[])
{
glutInit(&argc, argv);
//窗口使用RGB颜色，双缓存和深度缓存
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
glutInitWindowPosition(100, 100);
glutInitWindowSize(600, 400);
glutCreateWindow("旋转的立方体");
glutReshapeFunc(Reshape);
glutDisplayFunc(myDisplay);
glutIdleFunc(myDisplay);
Init();
glutMainLoop();
return 0;
}
