#include <stdlib.h>

#include "camera_gl.h"



#include <GL/glut.h>

static GLint Height;		/*height of window*/

static Camera_GL *TheCamera;


static Point3D Pyramid[] = {{0.0,0.0,0.0},{10.0,0.0,0.0},
                            {10.0,10.0,0.0},{0.0,10.0,0.0},
                            {5.0,5.0,40.0}};
                            
/*read in command line argument*/
int Eye;		/*- for L, + for R*/
float VPDistance;	/*view plane distance*/

/*preset half inter-pupilary distance*/
#define HIPD  1.5

static void displayPyramid(void)
{
	/*base*/
	glBegin(GL_POLYGON);
		glColor3f(0.0,0.0,0.0);
		glVertex3f(Pyramid[0].x,Pyramid[0].y,Pyramid[0].z);
		glVertex3f(Pyramid[3].x,Pyramid[3].y,Pyramid[3].z);
		glVertex3f(Pyramid[2].x,Pyramid[2].y,Pyramid[2].z);
		glVertex3f(Pyramid[1].x,Pyramid[1].y,Pyramid[1].z);
	glEnd();
	
	/*front*/
	glBegin(GL_POLYGON);
		glColor3f(1.0,0.0,0.0);
		glVertex3f(Pyramid[0].x,Pyramid[0].y,Pyramid[0].z);
		glVertex3f(Pyramid[1].x,Pyramid[1].y,Pyramid[1].z);
		glVertex3f(Pyramid[4].x,Pyramid[4].y,Pyramid[4].z);
	glEnd();
	
	/*right*/
	glBegin(GL_POLYGON);
		glColor3f(0.0,1.0,0.0);
		glVertex3f(Pyramid[1].x,Pyramid[1].y,Pyramid[1].z);
		glVertex3f(Pyramid[2].x,Pyramid[2].y,Pyramid[2].z);
		glVertex3f(Pyramid[4].x,Pyramid[4].y,Pyramid[4].z);
	glEnd();
	
	
	/*back*/
	glBegin(GL_POLYGON);
		glColor3f(0.0,0.0,1.0);
		glVertex3f(Pyramid[4].x,Pyramid[4].y,Pyramid[4].z);
		glVertex3f(Pyramid[2].x,Pyramid[2].y,Pyramid[2].z);
		glVertex3f(Pyramid[3].x,Pyramid[3].y,Pyramid[3].z);
	glEnd();
	
	/*left*/
	glBegin(GL_POLYGON);
		glColor3f(1.0,1.0,0.0);
		glVertex3f(Pyramid[0].x,Pyramid[0].y,Pyramid[0].z);
		glVertex3f(Pyramid[4].x,Pyramid[4].y,Pyramid[4].z);
		glVertex3f(Pyramid[3].x,Pyramid[3].y,Pyramid[3].z);
	glEnd();
}

static void display ()
{
    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
    displayPyramid();
    glFlush();
}
 
 
static void reshape(int width, int height)
{ 	
	setCOP_GL(TheCamera,(float)(HIPD*Eye),0.0,0.0);
	setVPDistance_GL(TheCamera,VPDistance);
	setClipPlanes_GL(TheCamera,0.1,200.0);
	setVPWindow_GL(TheCamera,-10.0,10.0,-10.0,10.0);

	clickProject_GL(TheCamera);
	
    	glViewport (0, 0, width, height); /*define the viewport*/
}
	
static void initialise(void) 
{

	/*GL_FLAT or GL_SMOOTH*/	
    	glShadeModel(GL_FLAT);
    
    	/*set the background (clear) Color to white*/
    	glClearColor(1.0,1.0,1.0,0.0);
	
	glEnable(GL_DEPTH_TEST);
	
    	/*set the depth buffer for clearing*/
    	glClearDepth(1.0);
 	
	/*initialise the camera*/
	TheCamera = newCamera_GL();
	setVRP_GL(TheCamera,5.0,5.0,100.0);
	setVPN_GL(TheCamera,0.0,0.0,-1.0);
	setVUV_GL(TheCamera,0.0,1.0,0.0);
	
	clickView_GL(TheCamera);
}

int main(int argc, char** argv)
{	
	int window;

	glutInit(&argc,argv);
	
	if(argc != 3){
		printf("stereo eye(-1 or 1) vpdistance\n");
		exit(0);
	}
	
	Eye = atoi(argv[1]);
	VPDistance = (float)atof(argv[2]);

	/*record the window height*/
	Height = 200;
	
	glutInitWindowSize(Height,Height);

	glutInitDisplayMode(GLUT_RGBA|GLUT_DEPTH);

	if(Eye < 0)  window = glutCreateWindow("Left");
	else
	if(Eye == 0) window = glutCreateWindow("Mono");
	else         window = glutCreateWindow("Right");
	
	glutSetWindow(window);

    	initialise();

	/*register callbacks*/
	glutDisplayFunc(display); /*display function*/
	glutReshapeFunc(reshape);

	glutMainLoop();
}