//house scene with depth testing added
#include <stdlib.h>
#include "glut.h"

#include <math.h>
#include <iostream>
GLfloat mat_specular[] = { 0.256777, 0.137622, 0.086014, 1.0 };
GLfloat mat_diffuse[] = { 0.7083, 0.27048, 0.0828, 1.0 };
GLfloat mat_ambient[] = { 0.19125, 0.0735, 0.0225, 1.0 };
GLfloat mat_shininess[] = { 12.8 };
GLfloat mat_specular1[] = { 0.136777, 0.137622, 0.136014, 1.0 };
GLfloat mat_diffuse1[] = { 0.19, 0.3, 0.9828, 1.0 };//{ 0.7083, 0.27048, 0.0828, 1.0 };
GLfloat mat_ambient1[] = { 0.09125, 0.2735, 0.5225, 1.0 };
GLfloat mat_shininess1[] = { 12.8 };
using namespace std;
void init(void);
void display(void);
void drawHouse(void);
static int theta = 0;
void init(void)
{

    glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular1);
    glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess1);
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse1);
    glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient1);

    GLfloat light_position[] = { 1.0, 1.0, 1.0, 0.0 };

    glShadeModel(GL_SMOOTH);


    glLightfv(GL_LIGHT0, GL_POSITION, light_position);

    glEnable(GL_LIGHTING);
    glEnable(GL_LIGHT0);

    glClearColor(0.6, 0.6, 0.7, 0.0);
    //glShadeModel(GL_FLAT);   //uses GL_SMOOTH or GL_FLAT
    glutInitDisplayMode(GLUT_DEPTH);
    glEnable(GL_DEPTH_TEST);
}

void keyboardread(unsigned char key, int x, int y)
{
    switch (key) {
    case 'r':
        theta = (theta + 10) % 360;
        glutPostRedisplay();
        cout << theta << endl;
        break;
    case 'l':
        theta = (theta - 10) % 360;
        glutPostRedisplay();
        break;
    }
}

void drawHouse(void)
{
    //Description:
    //This routine draws the house from OGL primitives
    //Note all polygon windings are counter clockwise
    //If you look at the front of a polygon its vertices are
    //listed so that the polygon is drawn in counterclockwise manner.
    //glPolygonMode(GL_FRONT_AND_BACK,GL_LINE);
    //  glPolygonMode(GL_BACK,GL_FILL); //uses also GL_FRONT_AND_BACK; GL_FILL, GL_POINT, GL_LINE  
    //  glPolygonMode(GL_FRONT,GL_FILL);// to spec. whether poly's. front and back are drawn filled
                                        // as lines or points

    //  glCullFace(GL_BACK);//discards front or back facing polygons
    //  glEnable(GL_CULL_FACE);  


    glBegin(GL_QUADS);

    glNormal3f(0.0, 0.0, 1.0);
    glVertex3f(0.0, 0.0, 0.0);//front norm is (0,0,1)
    glVertex3f(0.0, -2.0, 0.0);
    glVertex3f(1.0, -2.0, 0.0);
    glVertex3f(1.0, 0.0, 0.0);

    glNormal3f(1.0, 0.0, 0.0);
    glVertex3f(1.0, 0.0, 0.0);//right (1,0,0)
    glVertex3f(1.0, -2.0, 0.0);
    glVertex3f(1.0, -2.0, -1.0);
    glVertex3f(1.0, 0.0, -1.0);

    glNormal3f(-1.0, 0.0, 0.0);
    glVertex3f(0.0, 0.0, 0.0);//left (-1,0,0)
    glVertex3f(0.0, 0.0, -1.0);
    glVertex3f(0.0, -2.0, -1.0);
    glVertex3f(0.0, -2.0, 0.0);

    glNormal3f(0.0, -1.0, 0.0);
    glVertex3f(0.0, -2.0, 0.0); //bottom (0,-1,0)
    glVertex3f(0.0, -2.0, -1.0);
    glVertex3f(1.0, -2.0, -1.0);
    glVertex3f(1.0, -2.0, 0.0);

    glNormal3f(0.0, 0.0, -1.0);
    glVertex3f(0.0, 0.0, -1.0);//back (0,0,-1)
    glVertex3f(1.0, 0.0, -1.0);
    glVertex3f(1.0, -2.0, -1.0);
    glVertex3f(0.0, -2.0, -1.0);
    glEnd();
    glBegin(GL_TRIANGLES);
    glNormal3f(0.0, 0.0, 1.0);
    glVertex3f(0.0, 0.0, 0.0);//front gable (0,0,1)
    glVertex3f(1.0, 0.0, 0.0);
    glVertex3f(0.5, 1.25, 0.0);

    glNormal3f(0.0, 0.0, -1.0);
    glVertex3f(0.0, 0.0, -1.0);//back gable (0,0,-1)
    glVertex3f(0.5, 1.25, -1.0);
    glVertex3f(1.0, 0.0, -1.0);
    glEnd();
    glBegin(GL_QUADS);
    glNormal3f(-0.9385, 0.3714, 0.0);
    glVertex3f(0.0, 0.0, 0.0);//left roof (-0.9385,0.3714,0.0) 
    glVertex3f(0.5, 1.25, 0.0);
    glVertex3f(0.5, 1.25, -1.0);
    glVertex3f(0.0, 0.0, -1.0);

    glNormal3f(0.9385, 0.3714, 0.0);
    glVertex3f(0.5, 1.25, 0.0);//right roof (0.9385,0.3714,0.0)
    glVertex3f(1.0, 0.0, 0.0);
    glVertex3f(1.0, 0.0, -1.0);
    glVertex3f(0.5, 1.25, -1.0);
    glEnd();

}
void display(void)
{
    //select clearing background colour
    //if you don't do this then OGL will display
    //whatever was last drawn in the buffer
    //make it black
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    //glColor3f(0.0, 1.0, 1.0);//ignored if lighting is enabled
    glLoadIdentity();//reset transformation (of modelview matrix)

    gluLookAt(5.0 * sin(float(theta) * 0.0175), 5.0, 5.0 * cos(float(theta) * 0.0175), 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);
    //  place camera - it rotates about the origin, on y = 5.0 plane,
    // with a radius of 5.0; 0,0,0 - aim lens towards 0,0,0; 
    //  0,1,0 - the up vector defines an unique orientation
    
    drawHouse();
    glTranslatef(1.0, 0.0, 0.0);
    //glColor3f(0.0, 1.0, 0.0);
    glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
    glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
    glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient); 
    drawHouse();
    glTranslatef(2.0, 0.0, -1.0);
    glRotatef(90.0, 0.0, 1.0, 0.0);
    //glColor3f(0.0, 0.0, 1.0);
  /*  glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular1);
    glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess1);
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse1);
    glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient1); 
    drawHouse();*/
    //glutWireCube(1.0);
    //glFlush();
    glutSwapBuffers();
}
void reshape(int w, int h)
{
    glViewport(0, 0, w, h);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glFrustum(-1.0, 1.0, -1.0, 1.0, 1.5, 20.0);
    //             l,r,bot,top,near,far

    glMatrixMode(GL_MODELVIEW);
}

int main(int argc, char** argv)
{
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);
    glutInitWindowSize(250, 250);
    glutInitWindowPosition(100, 100);
    glutCreateWindow("3D house");
    init();
    glutReshapeFunc(reshape);
    glutDisplayFunc(display);
    glutKeyboardFunc(keyboardread);
    glutMainLoop();
    return 0;
}