CG 3 - COLOR CUBE AND SPIN IT

3. Draw a color cube and spin it using OpenGL transformation matrices. Modeling a Coloured Cube

#include<stdio.h>
#include<math.h>
#include<iostream>
#include<GL/glut.h>

float v[8][3] = { { -1,-1,-1 } ,{ -1,1,-1 } ,{ 1,1,-1 } ,{ 1,-1,-1 } , { -1,-1,1 } ,{ -1,1,1 } ,{ 1,1,1 } ,{ 1,-1,1 } };
int t[] = { 0,0,0 };
int ax = 2;

void init()
{
glMatrixMode(GL_PROJECTION);
glOrtho(-4, 4, -4, 4, -10, 10);
glMatrixMode(GL_MODELVIEW);
}

void polygon(int a, int b, int c, int d)
{
glBegin(GL_POLYGON);
glVertex3fv(v[a]);
glVertex3fv(v[b]);
glVertex3fv(v[c]);
glVertex3fv(v[d]);
glEnd();
}

void colorcube()
{
glColor3f(0, 0, 1);
polygon(0, 1, 2, 3);
glColor3f(0, 1, 1);
polygon(4, 5, 6, 7);
glColor3f(0, 1, 0);
polygon(0, 1, 5, 4);
glColor3f(1, 0, 0);
polygon(2, 6, 7, 3);
glColor3f(1, 1, 0);
polygon(0, 4, 7, 3);
glColor3f(1, 0, 1);
polygon(1, 5, 6, 2);
}

void spincube()
{
t[ax] += 1;
if (t[ax] == 360)
t[ax] -= 360;
glutPostRedisplay();
}

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

void display()
{
glClearColor(1, 1, 1, 1);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
glRotatef(t[0], 1, 0, 0);
glRotatef(t[1], 0, 1, 0);
glRotatef(t[2], 0, 0, 1);
colorcube();
glutSwapBuffers();
glFlush();
}

int main(int argc, char **argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);
glutInitWindowPosition(100, 100);
glutInitWindowSize(500, 500);
glutCreateWindow("Cube rotation");
init();
glutIdleFunc(spincube);
glutMouseFunc(mouse);
glEnable(GL_DEPTH_TEST);
glutDisplayFunc(display);
glutMainLoop();
return 0;
}

OUTPUT :

( click on image to zoom )