LAB3.cpp

#include<stdlib.h>
#include<GL/glut.h>

GLfloat vertices[]={-1.0,-1.0,-1.0,1.0,-1.0,-1.0,1.0,
					1.0,-1.0,-1.0,1.0,-1.0,-1.0,-1.0,1.0,
					1.0,-1.0,1.0,1.0,1.0,1.0,-1.0,1.0,1.0};

GLfloat colors[] = {0.0,0.0,0.0,1.0,0.0,0.0,1.0,1.0,0.0,
					0.0,1.0,0.0,0.0,0.0,1.0,1.0,0.0,
					1.0,1.0,1.0,1.0,0.0,1.0,1.0};

GLubyte cubeIndices[]={0,3,2,1,2,3,7,6,0,4,7,3,1,2,6,5,4, 5,6,7,0,1,5,4};
static GLfloat theta[]={0.0,0.0,0.0};
static GLint axis=2;

void display(void)
{
  glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
  glLoadIdentity();
  glRotatef(theta[0],1.0,0.0,0.0);
  glRotatef(theta[1],0.0,1.0,0.0);
  glRotatef(theta[2],0.0,0.0,1.0);
  glDrawElements(GL_QUADS,24,GL_UNSIGNED_BYTE, cubeIndices);
  glFlush();
  glutSwapBuffers();
}

void spinCube()
{
	theta[axis]+=2.0;
	if(theta[axis]>360.0) theta[axis]-=360.0;
		glutPostRedisplay();
}

void mouse(int btn, int state, int x, int y)
{
	if(btn==GLUT_LEFT_BUTTON && state==GLUT_DOWN)
		axis=0;
	if(btn==GLUT_MIDDLE_BUTTON&&state==GLUT_DOWN)
		axis=1;
	if(btn==GLUT_RIGHT_BUTTON&& state==GLUT_DOWN)
		axis=2;
}

void myReshape(int w, int h)
{
	glViewport(0,0,w,h);
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	if(w<=h)
		glOrtho(-2.0,2.0,-2.0*(GLfloat)h/(GLfloat)w, 2.0*(GLfloat)h/(GLfloat)w,-10.0,10.0);
	else
		glOrtho(-2.0*(GLfloat)w/(GLfloat)h, 2.0*(GLfloat)w/(GLfloat)h, -2.0,2.0,-10.0,10.0);
	glMatrixMode(GL_MODELVIEW);
}

void main(int argc, char **argv)
{
	glutInit(&argc, argv);
	glutInitDisplayMode(GLUT_DOUBLE|GLUT_RGB|GLUT_DEPTH);
	glutInitWindowSize(500,500);
	glutCreateWindow("Spin a color cube");
	glutReshapeFunc(myReshape);
	glutDisplayFunc(display);
	glutIdleFunc(spinCube);
	glutMouseFunc(mouse);
	glEnable(GL_DEPTH_TEST);	
	glEnableClientState(GL_COLOR_ARRAY);
	glEnableClientState(GL_VERTEX_ARRAY);
	glVertexPointer(3,GL_FLOAT, 0, vertices);
	glColorPointer(3, GL_FLOAT, 0, colors);
	glColor3f(1.0,1.0,1.0);
	glutMainLoop();
}