//
//  main.c
//  GEOMPRA-CV2b
//
//  Created by Jakub Mejtský on 27.02.12.
//  Copyright (c) 2012 __MyCompanyName__. All rights reserved.
//



#include <stdio.h>
#include <stdlib.h>
#include <GLUT/GLUT.h>
#include <math.h>

GLfloat X = 100.0f; // Translate screen to x direction (left or right)
GLfloat Y = 100.0f; // Translate screen to y direction (up or down)
GLfloat Z = 0.0f; // Translate screen to z direction (zoom in or out)
GLfloat rotX = 0.0f; // Rotate screen on x axis
GLfloat rotY = 0.0f; // Rotate screen on y axis
GLfloat rotZ = 0.0f; // Rotate screen on z axis

void onResize(int, int);
void onDisplay(void);
void onKeyboard(unsigned char, int, int);
void specialKey(int key, int x, int y);


void onResize(int w, int h)
{
    glViewport(0, 0, w, h);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glOrtho(0, w, 0, h, -1, 1);
}

void onDisplay(void)
{
    glClear(GL_COLOR_BUFFER_BIT);
    glClearColor(0.8, 0.8, 0.8, 0.0);
    glClear(GL_DEPTH_BUFFER_BIT);

    GLfloat A[] = {0.0f, 0.0f, 0.0f};
    GLfloat B[] = {100.0f, 0.0f, 0.0f};
    GLfloat C[] = {100.0f, 100.0f, 0.0f};
    GLfloat D[] = {0.0f, 100.0f, 0.0f};
    GLfloat E[] = {0.0f, 0.0f, 100.0f};
    GLfloat F[] = {100.0f, 0.0f, 100.0f};
    GLfloat G[] = {100.0f, 100.0f, 100.0f};
    GLfloat H[] = {0.0f, 100.0f, 100.0f};

    glPolygonMode(GL_FRONT, GL_FILL);
    glPolygonMode(GL_BACK, GL_FILL);
    glMatrixMode(GL_MODELVIEW);
    glDisable(GL_CULL_FACE);
    glEnable(GL_DEPTH_TEST);
    glLoadIdentity();

    glTranslatef(X, Y, Z);
    glRotatef(rotX,1.0,0.0,0.0); // Rotate on x
    glRotatef(rotY,0.0,1.0,0.0); // Rotate on y
    glRotatef(rotZ,0.0,0.0,1.0); // Rotate on z


    glColor3f(1.0f, 0.0f, 0.0f);
    glBegin(GL_POLYGON);
    glVertex3fv(A);
    glVertex3fv(B);
    glVertex3fv(C);
    glVertex3fv(D);
    glEnd();

    glColor3f(0.0f, 1.0f, 0.0f);
    glBegin(GL_POLYGON);
    glVertex3fv(E);
    glVertex3fv(F);
    glVertex3fv(G);
    glVertex3fv(H);
    glEnd();

    glColor3f(0.0f, 0.0f, 1.0f);
    glBegin(GL_POLYGON);
    glVertex3fv(B);
    glVertex3fv(F);
    glVertex3fv(G);
    glVertex3fv(C);
    glEnd();

    glColor3f(0.0f, 1.0f, 1.0f);
    glBegin(GL_POLYGON);
    glVertex3fv(A);
    glVertex3fv(E);
    glVertex3fv(H);
    glVertex3fv(D);
    glEnd();

    glColor3f(1.0f, 0.0f, 1.0f);
    glBegin(GL_POLYGON);
    glVertex3fv(A);
    glVertex3fv(B);
    glVertex3fv(F);
    glVertex3fv(E);
    glEnd();

    glColor3f(1.0f, 1.0f, 0.0f);
    glBegin(GL_POLYGON);
    glVertex3fv(D);
    glVertex3fv(C);
    glVertex3fv(G);
    glVertex3fv(H);
    glEnd();

    glFlush();
}

// This function is used for the navigation keys
void onKeyboard (unsigned char key, int x, int y){
    switch (key) {
        case 27: exit(0);
        case 'x': // Rotates screen on x axis
            rotX -= 1.0f;
            break;
        case 'X': // Opposite way
            rotX += 1.0f;
            break;
        case 'y': // Rotates screen on y axis
            rotY -= 1.0f;
            break;
        case 'Y': // Opposite way
            rotY += 1.0f;
            break;
        case 'z': // Rotates screen on z axis
            rotZ -= 1.0f;
            break;
        case 'Z': // Opposite way
            rotZ += 1.0f;
            break;
    }
        glutPostRedisplay();
}

void specialKey(int key, int x, int y) {
    switch(key) {
        case GLUT_KEY_LEFT : // Rotate on x axis
            X -= 2.0f;
            break;
        case GLUT_KEY_RIGHT : // Rotate on x axis (opposite)
            X += 2.0f;
            break;
        case GLUT_KEY_UP : // Rotate on y axis
            Y += 2.0f;
            break;
        case GLUT_KEY_DOWN : // Rotate on y axis (opposite)
            Y -= 2.0f;
            break;
        case GLUT_KEY_F1: // Rotate on z axis
            Z -= 2.0f;
            break;
        case GLUT_KEY_F2:// Rotate on z axis (opposite)
            Z += 2.0f;
            break;
    }
    glutPostRedisplay();
}

int main (int argc, char * argv[])
{
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_RGB);
    glutCreateWindow("Úkol Geometrické praktikum - CV2b");
    glutReshapeWindow(350, 350);
    glutPositionWindow(50, 50);
    glutDisplayFunc(onDisplay);
    glutReshapeFunc(onResize);
    glutKeyboardFunc(onKeyboard);
    glutSpecialFunc(specialKey);
    glutMainLoop();
    return 0;
}