/* File: oglexSphere2.c
*/

#include "stdio.h"
#include <cave_ogl.h>
#include <GL/glu.h>

void oglexInit(void);
void oglexDraw(void);

main(int argc, char **argv)
{
    /* Initialize the CAVE */
    CAVEConfigure(&argc,argv,NULL);
    CAVEInit();

    /* Give the library a pointer to the GL initialization function */
    CAVEInitApplication(oglexInit, NULL);

    /* Give the library a pointer to the drawing function */
    CAVEDisplay(oglexDraw, NULL);

    /* Wait for the escape key to be hit */
    while (!CAVEgetbutton(CAVE_ESCKEY))
	sginap(10);

    /* Clean up & exit */
    CAVEExit();
}


static GLUquadricObj *g_sphereObj;
static int g_ndraw = 0;

void oglexInit(void)
{
    glEnable(GL_LIGHT0);
    glEnable(GL_LIGHTING);
    g_sphereObj = gluNewQuadric();
}

void oglexDraw(void)
{
    float magenta[4] = { 1.0, 0.0, 1.0, 1.0 };
    float cyan[4] = { 0.0, 1.0, 1.0, 1.0 };
    double alpha;
    float x, y, z;

    alpha = 2.0*M_PI*((float)g_ndraw/(float)60);
    x = 3.0*cos(alpha);
    y = 5.0;
    z = 3.0*sin(alpha)-4.0;

    glClearColor(0., 0., 0., 0.);
    glClear(GL_DEPTH_BUFFER_BIT|GL_COLOR_BUFFER_BIT);

    glPushMatrix();
	glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, cyan);
	glTranslatef(0.0, 5.0, -4.0);
	gluSphere(g_sphereObj, 1.0, 15, 15);
    glPopMatrix();

    glPushMatrix();
	glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, magenta);
	glTranslatef(x, y, z);
	gluSphere(g_sphereObj, 1.0, 15, 15);
    glPopMatrix();

    g_ndraw++;
}