OpenGL（四）使用光源（独立）
#include
#include
#include
#include
#include
//旋转角度参数
static GLfloat xRot = 0.0f;
static GLfloat yRot = 0.0f;
//初始化窗口
void SetupRC(void)
{
//设置光源LINGT0的参数
GLfloat light_diffuse[] = { 1.0f, 1.0f, 1.0f,1.0f };
GLfloat light_ambient[] = { 0.0f, 0.5f, 0.5f, 1.0f };
glLightfv(GL_LIGHT0, GL_AMBIENT, light_ambient);
glLightfv(GL_LIGHT0,GL_DIFFUSE,light_diffuse);
//glLightfv(GL_LIGHT0,GL_AMBIENT,light_ambient);
//使光源有效
glEnable(GL_LIGHTING); //启动光照
glEnable(GL_LIGHT0); //启动光照符号常数
//开启深度测试
glEnable(GL_DEPTH_TEST);
//设置窗口背景西颜色为黑色
glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
}
void ChangeSize(int w, int h)
{
GLfloat nRange = 80.0f;
if (h == 0)
h = 1;
glViewport(0, 0, w, h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
//建立裁剪空间
gluPerspective(40.0f,(GLfloat)w/(GLfloat)h,1.0f,20.0f);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
}
void RenderScene(void)
{
//清除颜色及深度缓冲区 开启深度测试空间
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glPushMatrix();
//平移z负轴为了良好的效果
glTranslatef(0.0f,0.0f,-5.0f);
glPushMatrix();
glRotatef(xRot, 1.0f, 0.0f, 0.0f); //使黄色球绕着x轴旋转
glRotatef(yRot, 0.0, 1.0, 0.0f); //使黄色球绕着y轴旋转
// 光源设置位置
GLfloat position[] = { 0.0f, 0.0f, 1.5f, 1.0f };
glLightfv(GL_LIGHT0,GL_POSITION,position);
glTranslated(0.0f,0.0f,1.5f);
//绘制一个黄色的光球
glDisable(GL_LIGHTING);
glColor3f(1.0f,1.0f,0.0f);
glutSolidSphere(0.1f,50.f,50.f);
glEnable(GL_LIGHTING);
glPopMatrix(); //以下绘制的图案不会跟着旋转
//设置材质属性
GLfloat mat_diffuse[] = { 0.0, 0.5, 1.0, 1.0 };
glMaterialfv(GL_FRONT_AND_BACK,GL_DIFFUSE,mat_diffuse);
glutSolidTorus(0.275,0.85,50,50);
glPopMatrix();
glutSwapBuffers(); //刷新命令缓冲区
}
void SpecialKeys(int key, int x, int y)
{
if (key == GLUT_KEY_UP) xRot -= 5.0f;
if (key == GLUT_KEY_DOWN) xRot += 5.0f;
if (key == GLUT_KEY_LEFT) yRot -= 5.0f;
if (key == GLUT_KEY_RIGHT) yRot += 5.0f;
//结合glPushMatrix()和glPopMatrix()绘图模式理解旋转
// 首先，glPushMateix记住来的绘图坐标（起点）
//glRotatef(xRot, 1.0f, 0.0f, 0.0f);
//glRotatef(yRot, 0.0f, 1.0f, 0.0f);
//然后旋转相应的坐标后绘制图形
//glPopMatrix 回到了坐标原来的位置（起点）
printf("%lf\n", yRot);
if (xRot >= 360.0f) xRot = 0.0f;
if (xRot < -1.0f) xRot = 355.0f;
if (yRot >= 360.0f) yRot = 0.0f;
if (yRot < -1.0f) yRot = 355.0f;
//刷新窗口 强制
glutPostRedisplay();
}
int main(int argc, char *argv[])
{
//initialize the GLUT library
//初始化GLUT库
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB|GLUT_DEPTH);
glutCreateWindow("移动的光源");
//回调函数
glutDisplayFunc(RenderScene);
glutReshapeFunc(ChangeSize);
glutSpecialFunc(SpecialKeys);
SetupRC();
glutMainLoop();
return 0;
}
运行效果图：
学习点：
使用独立光源
GLfloat light_diffuse[] = { 1.0f, 1.0f, 1.0f,1.0f };
GLfloat light_ambient[] = { 0.0f, 0.5f, 0.5f, 1.0f };
glLightfv(GL_LIGHT0, GL_AMBIENT, light_ambient);
glLightfv(GL_LIGHT0,GL_DIFFUSE,light_diffuse);