/*
 * GLUT Shapes Demo
 *
 * Written by Nigel Stewart November 2003
 *
 * This program is test harness for the sphere, cone
 * and torus shapes in GLUT.
 *
 * Spinning wireframe and smooth shaded shapes are
 * displayed until the ESC or q key is pressed.  The
 * number of geometry stacks and slices can be adjusted
 * using the + and - keys.
 */

#ifdef __APPLE__
#include <GLUT/glut.h>
#else
#include <GL/glut.h>
#endif

#include <stdlib.h>
#include <math.h>

void drawTriangle(int R, int G, int B, float x1, float y1, float x2, float y2, float x3, float y3)
{
    glBegin(GL_TRIANGLES);
        glColor3ub(R, G, B);
        glVertex2f(x1, y1);
        glColor3ub(G, B, R);
        glVertex2f(x2, y2);
        glColor3ub(B, R, G);
        glVertex2f(x3, y3);
    glEnd();
}

void drawCircle(int points)
{
    glBegin(GL_LINE_LOOP);
    //set the color in 3 float number (red, green, blue)
    glColor3f(0.0, 1.0, 0.0);

   float angle, x, y;
   for (int i = 0; i < points; i++){
    angle = 6.2832 * i / points;
    x = 0.5 * cos(angle);
    y = 0.5 * sin(angle);
    glVertex2f(x, y);
   }
    glEnd();
}
void square(float R, float G, float B){
glColor3f(R,G,B);
glBegin(GL_POLYGON);
glVertex3f(0, 0, 0.5);
glVertex3f(0.5, 0, 0.5);
glVertex3f(0.5, 0.5, 0.5);
glVertex3f(0, 0.5, 0.5);
glEnd();
}
void cube(float size){
glPushMatrix(); //save a copy of the current matrix
glScalef(size,size,size);
square(1, 0, 0); //red color side
glPushMatrix();
glRotatef(90, 0, 1, 0); //rotate by y
square(0, 1, 0); //green color side
glPopMatrix();
glPushMatrix();
glRotatef(-90, 1, 0, 0);
square(0, 0, 1);
glPopMatrix();
glPushMatrix();
glRotatef(180, 0, 1, 0);
square(0, 1, 1);
glPopMatrix();
glPushMatrix();
glRotatef(-90, 0, 1, 0);
square(1, 0, 1);
glPopMatrix();
glPushMatrix();
glRotatef(90, 1, 0, 0);
square(1, 1, 0);
glPopMatrix();
glPopMatrix(); // restore matrix to its state before cube() was created.
}
void display(){
//clear memory color buffer
    glClear(GL_COLOR_BUFFER_BIT);
    glLoadIdentity();
    //drawTriangle(66, 135, 245, -0.5, -0.5, 0.5, -0.5, 0, 0.5);
    //drawCircle(64);
    //drawTriangle(0, 0, 255, -1, -1, 0, 1, 1, -1);
    //glTranslatef(0.00005, 0.0, 0.0);
    static double x = 15;
    x = x + 0.15;
    glRotatef(x,0,0,1);


    glPushMatrix();
    drawTriangle(0, 0, 255, 0, 0, 0.5, 0.5, 0.5, 0);
    glPopMatrix();

    glPushMatrix();
    drawTriangle(0, 0, 255, 0, 0, -0.5, -0.5, -0.5, 0);
    glPopMatrix();

    glPushMatrix();
    drawTriangle(0, 0, 255, 0, 0, 0, -0.5, 0.5, -0.5);
    glPopMatrix();

    glPushMatrix();
    drawTriangle(0, 0, 255, 0, 0, 0, 0.5, -0.5, 0.5);
    glPopMatrix();



    /*drawTriangle(247, 128, 30,-0.5,0.5,0.5,1,0,0.5);

    glPushMatrix();
    glTranslatef(0.03, 0, 0);
    glScalef(0.4,0.5,0.7);
    glRotatef(150,0,1,0);
    drawTriangle(64, 135, 255, 0.5,0.5,0.5,-0.5,-0.5,-0.5);
    glPopMatrix();
*/
    /*glPushMatrix();
    glTranslatef(0.00005, 0.0, 0.0);
    drawTriangle(0, 0, 255, -1, -1, 0, 1, 1, -1);
    glPopMatrix();*/

//switch
 //memory buffer
    glutSwapBuffers();
}
    //reshape windows
void reshape(int WIDTH, int HEIGHT){
 //sets viewport size from X to win width and from Y to win height
    glViewport(0, 0, WIDTH, HEIGHT);
}

void onInit(){
//glClearColor(R,G,B,A) sets windows background RGB color + alpha channel
    glClearColor(0.0, 0.0, 0.0, 1.0);
}

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

    //glutInit is used to initialize the GLUT library
    glutInit(&argc, argv);

    // glutInitDisplayMode sets the initial display modes
    glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA | GLUT_DEPTH);
   // glutInitWindowSize sets windows size in pixels (W, H)
    glutInitWindowSize(720, 720);
   // glutWindowsPosition sets windows position, from left down corner
    glutInitWindowPosition(100,100);
   // glutCreateWindows create windows and sets windows title
    glutCreateWindow ("My first OpenGL Windows");

    onInit();

    glutDisplayFunc(display);
    glutIdleFunc(display);
    glutReshapeFunc(reshape);
    glutMainLoop();

    return 0;
    }