OpenGL ES 光源设置

	//Enabel lighting
	glEnable(GL_LIGHTING);
	
	// Turn the first light on
	glEnable(GL_LIGHT0);
	
	//环境光
	const GLfloat light0Ambient[] = {0.1, 0.1, 0.1, 1.0};
	glLightfv(GL_LIGHT0, GL_AMBIENT, light0Ambient);
	
	//散射光
	const GLfloat light0Diffuse[] = {0.7, 0.7, 0.7, 1.0};
	glLightfv(GL_LIGHT0, GL_DIFFUSE, light0Diffuse);
	
	//高光
	const GLfloat light0Specular[] = {0.7, 0.7, 0.7, 1.0};
	const GLfloat light0Shininess = 0.4;
	glLightfv(GL_LIGHT0, GL_SPECULAR, light0Specular);
	
	//位置
	const GLfloat light0Position[] = {0.0, 10.0, 10.0,0.0};
	glLightfv(GL_LIGHT0, GL_POSITION, light0Position);
	
	//方向
	const GLfloat light0Direction[] = {0.0, 0.0, -1.0};
	glLightfv(GL_LIGHT0, GL_SPOT_DIRECTION, light0Direction);
	
	//指定光的角度
	glLightf(GL_LIGHT0, GL_SPOT_CUTOFF, 45.0);
	
	glLoadIdentity();