#include <GL/gl.h>
#include <GL/glut.h>
#include <cmath>
#include <cstdio>
#include <iostream>
using namespace std;

bool timeChange = true;
bool showKeyCode = false;
bool keypressed[10] = {};

GLfloat PI2 = 6.283185307179586;

GLfloat param = 0;

GLfloat ToroidR = 30;
GLfloat Toroidr = 10;

GLfloat Xrotation = 0.0;
GLfloat Yrotation = 0.0;
GLfloat Zrotation = 0.0;
GLfloat RotationSpeed = 2.5;

GLint CoordinatResolutionX = 100;
GLint CoordinatResolutionY = 100;
GLint CoordinatResolutionZ = 100;


void display() {

  glClearColor(0.1, 0.1, 0.1, 1);

  glClear(GL_COLOR_BUFFER_BIT);

  glLoadIdentity();

  glPointSize( 5 );



  glRotatef(Xrotation, 1.0f, 0.0f, 0.0f);
  glRotatef(Yrotation, 0.0f, 1.0f, 0.0f);
  glRotatef(Zrotation, 0.0f, 0.0f, 1.0f);




  for( int x = -50; x < 100; x+=1 )
    for( int y = -50; y < 100; y+=1 )
      for( int z = -50; z < 100; z+=1 ){
        float tor = ( x * x + y * y + z * z + ToroidR * ToroidR - Toroidr * Toroidr) * ( x * x + y * y + z * z + ToroidR * ToroidR - Toroidr * Toroidr) - 4 * ToroidR * ToroidR * ( x * x + y * y );

        if ( tor >= -20000 && tor <= 20000 ){
          GLfloat r = ( x + 50 ) / 100.0;
          GLfloat g = ( y + 50 ) / 100.0;
          GLfloat b = ( z + 50 ) / 100.0;
          //GLfloat size = ( ( ( x + y + 100 ) / 200.0 ) ) * 1 * 10;
          GLfloat size = ( sin( ( x + y + z ) / 100.0 * 6 + param ) / 3.0 + 0.5 ) * 10 ;


          glColor3f( r, g, b );

          glPointSize(size);

          glBegin(GL_POINTS);
            glVertex3f(x,y,z);
          glEnd();
        }
      }



/*
    for( int i = 0; i < point_count; i++ ){
      GLfloat r = i / (float)(point_count);
      GLfloat g = cos( i / (float)(point_count) * PI2 ) ;
      GLfloat b = 0.3 + (  ( sin( param  ) + 1 ) / 5.0 );

      glColor3f( r, g, b );

      GLfloat x = ( ( i / (float)(point_count) * CoordinatResolutionX ) ) - ( CoordinatResolutionX / 2.0 );
      GLfloat y = sin( param + i * 0.3 ) * 10;
      glVertex3f( x, y, 0 );

    }
*/



  glColor3f( 1,1,1 );
  glBegin(GL_LINES);
    glVertex3f( -50, 0, 0 );
    glVertex3f( 50, 0, 0 );

    glVertex3f( 45, -5, 0 );
    glVertex3f( 50, 0, 0 );
    glVertex3f( 45, 5, 0 );
    glVertex3f( 50, 0, 0 );


    glVertex3f( 0, -50, 0 );
    glVertex3f( 0, 50, 0 );

    glVertex3f( -5, 45, 0 );
    glVertex3f( 0, 50, 0 );
    glVertex3f( 5, 45, 0 );
    glVertex3f( 0, 50, 0 );

  glEnd();


  glutSwapBuffers();
}

void ChangeSize(GLsizei w, GLsizei h){

  GLfloat aspectRatio;
  if (h == 0)
    h = 1;
  glViewport(0, 0, w, h);
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  aspectRatio = (GLfloat)w / (GLfloat)h;
  if (w <= h) {
    GLfloat windowWidth = (CoordinatResolutionX / 2.0);
    GLfloat windowHeight = ( CoordinatResolutionY / 2.0 ) / aspectRatio;
    glOrtho(-CoordinatResolutionX/2.0, CoordinatResolutionX/2.0, -windowHeight, windowHeight, -CoordinatResolutionZ/2.0, CoordinatResolutionZ/2.0);
  } else {
    GLfloat windowWidth = ( CoordinatResolutionX / 2.0 ) * aspectRatio;
    GLfloat windowHeight =( CoordinatResolutionY / 2.0 );
    glOrtho(-windowWidth, windowWidth, -CoordinatResolutionY/2.0, -CoordinatResolutionY/2.0, -CoordinatResolutionZ/2.0, CoordinatResolutionZ/2.0);
  }
  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();
}



void inc( int x ){
  if ( timeChange )
    param += 0.02 * x;

  if ( keypressed[1] )
    Xrotation += RotationSpeed;
  if ( keypressed[2] )
    Xrotation -= RotationSpeed;
  if ( keypressed[3] )
    Yrotation += RotationSpeed;
  if ( keypressed[4] )
    Yrotation -= RotationSpeed;
  if ( keypressed[5] )
    Zrotation += RotationSpeed;
  if ( keypressed[6] )
    Zrotation -= RotationSpeed;


  glutPostRedisplay();
  glutTimerFunc(16, inc , 3);
}



void keyDown ( int key, int x, int y)
{
  if( showKeyCode )
    std::cout << "keydown " << key << "\n";

  if( key == GLUT_KEY_END && !keypressed[0] ){
    timeChange = !timeChange;
    keypressed[0] = true;
  }

  if( key == GLUT_KEY_UP && !keypressed[1] ){
    keypressed[1] = true;
  }
  if( key == GLUT_KEY_DOWN && !keypressed[2] ){
    keypressed[2] = true;
  }
  if( key == GLUT_KEY_LEFT && !keypressed[3] ){
    keypressed[3] = true;
  }
  if( key == GLUT_KEY_RIGHT && !keypressed[4] ){
    keypressed[4] = true;
  }
  if( key == GLUT_KEY_PAGE_UP && !keypressed[5] ){
    keypressed[5] = true;
  }
  if( key == GLUT_KEY_PAGE_DOWN && !keypressed[6] ){
    keypressed[6] = true;
  }
}

void keyUp ( int key, int x, int y)
{
  if( showKeyCode )
    std::cout << "keyup " << key << "\n";

  if( key == GLUT_KEY_END ){
    keypressed[0] = false;
  }

  if( key == GLUT_KEY_UP ){
    keypressed[1] = false;
  }
  if( key == GLUT_KEY_DOWN ){
    keypressed[2] = false;
  }
  if( key == GLUT_KEY_LEFT ){
    keypressed[3] = false;
  }
  if( key == GLUT_KEY_RIGHT ){
    keypressed[4] = false;
  }
  if( key == GLUT_KEY_PAGE_UP ){
    keypressed[5] = false;
  }
  if( key == GLUT_KEY_PAGE_DOWN ){
    keypressed[6] = false;
  }
}

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

  glutInit(&argc, argv);
  glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);

  glutInitWindowPosition(1228,500);

  glutInitWindowSize(1000, 1000);
  glutCreateWindow("float");

  glutSetKeyRepeat(GLUT_KEY_REPEAT_OFF);
  glutSpecialFunc(keyDown);
  glutSpecialUpFunc(keyUp);


  glutDisplayFunc(display);
  glutReshapeFunc(ChangeSize);
  glutTimerFunc(16, inc , 3);

  glutMainLoop();

  return 0;
}