//cubewithlight
//  Demonstration of shading and lighting with moving cube
//  The function "myInitView" prepares the view with lighting.
//  The function "putFlatPolygon" draw a polygon with setting the normal
//  vector to the polygon.
//  In the function "glMaterialfv" the keyword "GL_AMBIENT" means the reflection color
//  for the ambient light.
//  flat shading
// T. Kosaka CS TNCT 16Aug2002

#include <stdio.h>
#include <math.h>
#include <GL/glut.h>
#include "GLDrawingtool3D.h"
#ifndef M_PI
#define M_PI 3.141592653589793
#endif

void userdraw(void);

GLfloat light0pos[] = { 500.0, 500.0, 1500.0, 0.0 }; // x,y,z,d
GLfloat White[] = { 1.0, 1.0, 1.0, 1.0 }; // R,G,B,A
GLfloat Cyan[] = { 0.0, 1.0, 1.0, 1.0 }; // R,G,B,A
GLfloat Gray[] = { 0.2, 0.2, 0.2, 1.0 }; // R,G,B,A
GLfloat Red[] = { 1.0, 0.0, 0.0, 1.0 }; // R,G,B,A
GLfloat Shine[] = { 20.0}; //0.0(large highlight) ... 128.0(small highlight)

void display(void)
{
    glClear( GL_COLOR_BUFFER_BIT);
    glClear(GL_DEPTH_BUFFER_BIT); // depth check
    userdraw();
    glutSwapBuffers();
}

void userdraw(void)
{
    static int tick=0;
    float k1=tick/200.;

    polyhedron_t cube={
        8, //number of vertices of the cube
        {
            {50,50,50},{50,50,-50},{-50,50,-50},{-50,50,50},
            {50,-50,50},{50,-50,-50},{-50,-50,-50},{-50,-50,50}
        }, // coordinates of the vertices of the cube
        6, // number of faces of the cube
        {
            {4,{0,1,2,3},{0,1,0}}, {4,{0,4,5,1},{1,0,0}},
            {4,{1,5,6,2},{0,0,-1}}, {4,{2,6,7,3},{-1,0,0}},
            {4,{3,7,4,0},{0,0,1}}, {4,{7,6,5,4},{0,-1,0}}
        } // every face has four vertices and showing vertex numbers
    };

    myInitView(1);

    glRotatef(k1*360.0, 0.0, 1.0, 0.0); // Matrix A
    glTranslatef(200.0, 0.0, 0.0);      // Matrix B
    glRotatef(k1*360.0, 0.0, 0.0, 1.0); // Matrix C
    // Then Transformation Matrix for the cube is A*B*C

    glMaterialfv(GL_FRONT, GL_AMBIENT, Gray); //Attribute of the cube
    glMaterialfv(GL_FRONT, GL_DIFFUSE, Cyan);
    glMaterialfv(GL_FRONT, GL_SPECULAR, White);
    glMaterialfv(GL_FRONT, GL_SHININESS, Shine);

    putFlatPolyhedron(cube);
    tick++;
}

int main(int argc, char **argv)
{
    glutInit(&argc,argv);
    glutInitDisplayMode ( GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH); // depth check
    glutInitWindowPosition(100,100);
    glutInitWindowSize(640,480);
    glutCreateWindow ("cubewithlight");
    glClearColor(0.0, 0.0, 0.0, 0.0);
    glViewport(0,0,640,480);               
    glutIdleFunc(display); // idle event call back
    glutDisplayFunc(display);
    glEnable(GL_DEPTH_TEST); // depth check (OpenGL inner Z-Buffer)
    glutMainLoop();
    return 0;
}