/*****************************************************
 *
 *                   TwoCube.c
 *
 *  Jason Ng 100383886
 *
 *  Question 1b - Assignment 1
 *  Displays 2 cubes rotating in opposite directions
 *
 *****************************************************/
 
// standard include files required by all GLUT programs

#include <windows.h>
#include <GL/gl.h>
#include <GL/glu.h>
#include <GL/glut.h>
#include <stdio.h>
 
int window;         // the window id of the window in our program
float translateCube = -40.0;
float fov = 45.0;

void gfxinit() {
    // enable the depth buffer
    glEnable(GL_DEPTH_TEST);
    // set the projection to perspective
    glMatrixMode(GL_PROJECTION);
    gluPerspective(1.0*fov, 1.0, 1.0, 60.0);
    // set up the viewing transformation
    // the view is at (0, 3, 0) and they are looking at (0,0,0)
    // the up direction is (0, 0, 1) - the z axis
    glMatrixMode(GL_MODELVIEW);
    gluLookAt(10.0, 10.0, 10.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);
}
 
void display() { 
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    //glColor3f(1, 1, 1);
    //glutSolidCube(1.0);
    for (int count = 0; count < 20; count++) {
        float r = (1.0*(rand()%11))/10;
        float g = (1.0*(rand()%256))/256.0;
        float b = (1.0*(rand()%256))/256.0;
        translateCube = translateCube + 2.5;
        glTranslatef(translateCube, 0.0, 0.0);
        glColor3f(r, g, b);
        glutSolidCube(1.0);
        translateCube = 0.0;
    }
    glutSwapBuffers();
}     

void keyboard(unsigned char key, int x, int y) {
    switch (key) {
           case 'z':
                fov -= 5.0;
                if (fov <= 10.0) {
                   fov = 10.0;
                }            
                printf ("Field Of View is now %4.1f\n", fov);
                break;
           case 'x':
                fov += 5.0;
                if (fov >= 120.0)
                   fov = 120.0;
                printf ("Field Of View is now %4.1f\n", fov);
                break;
           case 'q':
                exit(0);
                break;
           default:
                break;
    }
}

/*
 * The main function
 */
 
int main(int argc, char **argv) { 
    // Initialize GLUT and process its command line arguments
    glutInit(&argc,argv);
    // Set the display mode, double buffered, RGB colour and depth buffer
    glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
    glutInitWindowSize(600, 600);
    // Create the display window
    window = glutCreateWindow("Assignment 1");
    // Set the display function
    glutDisplayFunc(display);
    glutKeyboardFunc(keyboard);
    // Set the Idle function, called when GLUT isn't busy
    // Initialize OpenGL
    gfxinit();
    // Pass control to GLUT to run the application
    glutMainLoop();
}