Why isn't this opengl background and lighting working?
#include<iostream>
#include<stdlib.h>
#ifdef __APPLE__
#include<OpenGL/OpenGL.h>
#include<GLUT/glut.h>
#else
#include<GL/glut.h>
#endif
#include<math.h>
// g++ rotateCube.cpp -lm -lglut -lGL -lGLU
using namespace std;
void handleResize(int w, int h);
void drawCube();
void update(int value);
void initRendering();
//The coordinates for vertices of the cube
double x=0.6;
double y=0.6;
double z=0.6;
float angle=0.0;
void drawCube()
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
// Reset transformations
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glTranslatef(0.0,0.0,-5.0);
//Add ambient light
GLfloat ambientColor[]={0.2,0.2,0.2,1.0};
glLightModelfv(GL_LIGHT_MODEL_AMBIENT, ambientColor);
//Add a positioned light
GLfloat lightColor0[]={0.5,0.5,0.5,1.0};
GLfloat lightPos0[]={4.0,0.0,8.0,1.0};
glLightfv(GL_LIGHT0,GL_DIFFUSE, lightColor0);
glLightfv(GL_LIGHT0,GL_DIFFUSE, lightPos0);
glTranslatef(0.5,1.0,0.0);
glRotatef(angle,1.0,1.0,1.0);
glRotatef(angle,1.0,0.0,1.0);
glRotatef(angle,0.0,1.0,1.0);
glTranslatef(-0.5,-1.0,0.0);
//Create the 3d cube
//BACK
glBegin(GL_POLYGON);
glColor3f(0.5,0.3,0.2);
glVertex3f(x,-y,z);
glVertex3f(x,y,z);
glVertex3f(-x,y,z);
glVertex3f(-x,-y,z);
glEnd();
//FRONT
glBegin(GL_POLYGON);
glColor3f(0.0,0.5,0.0);
glVertex3f(-x,y,-z);
glVertex3f(-x,-y,-z);
glVertex3f(x,-y,-z);
glVertex3f(x,y,-z);
glEnd();
//LEFT
glBegin(GL_POLYGON);
glColor3f(0.5,0.5,0.5);
glVertex3f(-x,-y,-z);
glVertex3f(-x,-y,z);
glVertex3f(-x,y,z);
glVertex3f(-x,y,-z);
glEnd();
//RIGHT
glBegin(GL_POLYGON);
glColor3f(0.0,0.0,0.0);
glVertex3f(x,-y,-z);
glVertex3f(x,-y,z);
glVertex3f(x,y,-z);
glVertex3f(x,y,-z);
glEnd();
//TOP
glBegin(GL_POLYGON);
glColor3f(0.6,0.0,0.0);
glVertex3f(x,y,z);
glVertex3f(-x,y,z);
glVertex3f(-x,y,-z);
glVertex3f(x,y,-z);
glEnd();
//BOTTOM
glBegin(GL_POLYGON);
glColor3f(0.3,0.0,0.3);
glVertex3f(-x,-y,-z);
glVertex3f(-x,-y,z);
glVertex3f(x,-y,z);
glVertex3f(x,-y,-z);
glEnd();
glFlush();
glutSwapBuffers();
}
// Function for increasing the angle variable smoothly,
// keeps it <=360
//It can also be implemented using the modulo operator
void update(int value)
{
angle+=1.0f;
if(angle>360)
{
angle-=360;
}
glutPostRedisplay();
glutTimerFunc(25, update, 0);
}
//Initializes 3D rendering
void initRendering()
{
glEnable(GL_DEPTH_TEST);
glEnable(GL_COLOR_MATERIAL);
//Set the color of the background
glClearColor(0.7f,0.8f,1.0f,1.0f);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
glEnable(GL_NORMALIZE);
}
// Called when the window is resized
void handleResize(int w, int h)
{
glViewport(0,0,w,h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(45.0,(double)w/(double)h,1.0,200.0);
}
int main(int argc, char **argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
glutInitWindowSize(700,700);
glutInitWindowPosition(100,100);
glutCreateWindow("OpenGL - Rotating a Cube");
glutDisplayFunc(drawCube);
glutReshapeFunc(handleResize);
// Add a timer for the update(...) function
glutTimerFunc(25, update, 0);
glutMainLoop();
return 0;
}
