/*
  Demo to demonstrate the properties of vectors in 2-dimensional space
*/

#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <GL/glut.h>
#include "tw.h"

#define GAP  25      /* gap between subwindows */
int leftWinWidth=400;
int leftWinHeight=400;
int rightWinWidth=400;
int rightWinHeight=400;

void parentDisplay(void) {
    twDisplayInit();
    glFlush();
    glutSwapBuffers();
}

GLfloat aspectRatio(int w, int h) {
    return ((GLfloat) w) / ((GLfloat) h);
}

void leftDisplay(void) {
    twDisplayInit();
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective(90,aspectRatio(leftWinWidth,leftWinHeight),2,6);
    // gluPerspective(90,1.94,0.7,4.2);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    gluLookAt(0,0,4, 0,0,0, 0,1,0);
    twSetMessages(TW_ALL_MESSAGES);
    //twCamera();

    twColorName(TW_MAGENTA);
    glutWireCube(1);
  
    glFlush();
    glutSwapBuffers();
}

void rightDisplay(void) {
    twDisplayInit();
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective(2*atan(2.0/22.0),aspectRatio(rightWinWidth,rightWinHeight),20,24);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    gluLookAt(0,0,0, 0,0,-22, 0,1,0);

    twColorName(TW_YELLOW);
    glutWireCube(1);
  
    glFlush();
    glutSwapBuffers();
}

int parentWin, leftWin, rightWin;

int main(int argc, char** argv) {
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE);
    glutInitWindowSize(leftWinWidth+rightWinWidth+GAP*3, 
		       leftWinHeight+GAP*2); //parent window
    parentWin = glutCreateWindow(argv[0]);
    glutDisplayFunc(leftDisplay);
    twBoundingBox(-1,1,-1,1,-1,1); // keeps twMainInit quiet
    twMainInit();

    glutMainLoop();
    return 0;
}