// ------------------------------------------------------------------
//   This code was written by Philipp Seifried, except where
//   otherwise stated.
//   You're permitted to do whatever you want with the parts
//   I wrote, including modification, distribution and 
//   removal of this notice, as long as I will not be held
//   responsible for any harm that results in the use of
//   this code.
//   Remember that for this to work, you will also need the
//   JOGL classes to be found at
//   https://jogl.dev.java.net/
//   For instructions, refer to
//   http://www.repeatwhiletrue.com/p5/P5JOGL.html

//   Have fun!
// ------------------------------------------------------------------

Frame oglFrame; // our openGL Window
GLCanvas canvas; // the component openGL will render to
JOGLRenderer renderer; // our custom event listener that will do the rendering
boolean fullscreen;
KeyInputHandler keyHandler;
MouseInputHandler mouseHandler;
int oglMouseX, oglMouseY, oglPMouseX, oglPMouseY;

// ----------------- Add your own stuff here!
float ourVariable; // We will use this one to do some fancy color warping.
float ourZ;
// ------------------------------------------

void setup() {

  // ----------------- Add your own stuff here!
  size(320,240);
  ourVariable = 0;
  ourZ = -3;
  fullscreen = true;
  keyHandler = new KeyInputHandler();
  mouseHandler = new MouseInputHandler();
  //    ...
  //    ...
  //    ...
  // ------------------------------------------

  // set up our window
  oglFrame = new Frame("Our very own OpenGL Window!");
  oglFrame.setSize( 800, 600 );

  renderer = new JOGLRenderer();

  // set the properties of our openGL component...
  GLCapabilities glCaps = new GLCapabilities();
  glCaps.setRedBits(8); // 32 bit color resolution
  glCaps.setBlueBits(8);
  glCaps.setGreenBits(8);
  glCaps.setAlphaBits(8);
  glCaps.setDoubleBuffered(false); // double buffered
  canvas = GLDrawableFactory.getFactory().createGLCanvas( glCaps );
  // add the renderer to the component and the component to our window.
  canvas.addGLEventListener(renderer);
  canvas.addKeyListener(keyHandler);
  canvas.addMouseListener(mouseHandler);
  canvas.addMouseMotionListener(mouseHandler);
  oglFrame.add( canvas );

  // let the program exit if our openGL window is shut down.
  oglFrame.addWindowListener(new WindowAdapter() {
    public void windowClosing(WindowEvent e) {
      if (fullscreen) {
        GraphicsEnvironment ge=null;
        GraphicsDevice gd=null;
        ge = GraphicsEnvironment.getLocalGraphicsEnvironment();  
        gd = ge.getDefaultScreenDevice();  
        if( gd.isFullScreenSupported() )
        {  
          gd.setFullScreenWindow(null);  
        } 
      }
      System.exit(0);
    }
  });


  if (fullscreen) {
    oglFrame.setUndecorated(true); // We don't want any title bar for this window
    GraphicsEnvironment ge=null;
    GraphicsDevice gd=null;
    ge = GraphicsEnvironment.getLocalGraphicsEnvironment();  
    gd = ge.getDefaultScreenDevice();  
    if( gd.isFullScreenSupported() )
    {  
      gd.setFullScreenWindow(oglFrame);  
    } 
  }
  
  // show our openGL window!
  oglFrame.setVisible(true); 
  oglFrame.setFocusable(true);
  oglFrame.requestFocus();
}

void loop() {
  // ----------------- Add your own stuff here!
  if (mousePressed) {
    ourVariable += 0.1;
  }
  //    ...
  //    ...
  //    ...
  // ------------------------------------------
  canvas.display();
}


class JOGLRenderer implements GLEventListener
{
  boolean isFirstFrame;

  public void init(GLDrawable drawable)
  {
    // fetch GL and GLU instances from our GLCanvas
    GL gl = drawable.getGL();
    GLU glu = drawable.getGLU();  
    isFirstFrame = true;
    
    // ----------------- Add your own stuff here!
    gl.glShadeModel(GL.GL_SMOOTH); // enable smooth shading
    gl.glClearColor(0.0f, 0.0f, 0.0f, 0.0f); // set the background color
    gl.glHint(GL.GL_PERSPECTIVE_CORRECTION_HINT, GL.GL_NICEST); // nice perspective correction
    gl.glEnable(GL.GL_DEPTH_TEST); // enable the z-Buffer
    gl.glDepthFunc(GL.GL_LEQUAL); // the z comparison function
    gl.glClearDepth(1.0f); // set the depth the z-Buffer will be cleared to
    gl.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT ); // clear the screen
    glu.gluPerspective(45.0f,(float)(800)/(float)(600),0.1f,100.0f); // and set up a perspective.
    // ------------------------------------------
    
  }

  public void display(GLDrawable drawable)
  {
    // -------- this is our render loop!
    GL gl = drawable.getGL(); // gl should be fetched like this in every frame...
    if (isFirstFrame) {
      isFirstFrame = false;
      gl.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT ); // clear the screen
    }
    // ----------------- Add your own stuff here!
    ourZ += 0.02;
    if (ourZ > -1) {ourZ = -3;}
    
    if (mousePressed) { // If the mouse is pressed...
    float a = sin(ourVariable)/2+0.5;
    float b = sin(ourVariable*1.3)/2+0.5;
    float c = sin(ourVariable*1.9)/2+0.5;
    // mouse coordinates are pixel distances from the top left corner of the window.
    // we will need to convert them to floating point values ranging from -1 to 1
    float x = ((float) oglMouseX / (float) drawable.getSize().getWidth())*2-1;
    float y = -(((float) oglMouseY / (float) drawable.getSize().getHeight())*2-1);
    gl.glBegin( GL.GL_TRIANGLES ); // draw a triangle
    gl.glColor3f(a, 0.5, c);
    gl.glVertex3f( x, y+0.1, ourZ );
    gl.glColor3f(0.5, 1-a, b);
    gl.glVertex3f( x-0.1, y-0.1, ourZ );
    gl.glColor3f(c, 1-c, 1);
    gl.glVertex3f( x+0.1, y-0.1, ourZ );
    gl.glEnd();
    }
    if (keyPressed && key == ' ') { // If the spacebar is pressed...
      gl.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT ); // clear the screen
    }
    // ------------------------------------------
    
    // update the "previous Mouse" positions
    oglPMouseX = oglMouseX;
    oglPMouseY = oglMouseY;
  }

  public void reshape(GLDrawable drawable, int x, int y, int width, int height)
  {
    // -------- this will be called whenever our openGL window is resized!
    GL gl = drawable.getGL(); // gl should be fetched like this in every frame...
    gl.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT ); // clear the screen
  }

  public void displayChanged(GLDrawable drawable, boolean modeChanged, boolean deviceChanged)
  {
    // -------- this is not implemented in JOGL yet. Best to leave it alone.
  }
} 

class KeyInputHandler extends KeyAdapter {
  public void keyPressed(KeyEvent e) {
    key = e.getKeyChar();
    keyPressed = true;
    // ----------------- Add your own stuff here!
    //                 ...
    // ------------------------------------------
  } 
    
  public void keyReleased(KeyEvent e) {			
    key = e.getKeyChar();
    keyPressed = false;
    // ----------------- Add your own stuff here!
    //                 ...
    // ------------------------------------------
  }

  public void keyTyped(KeyEvent e) {
    key = e.getKeyChar();
    if (e.getKeyChar() == 27) { // Escape key closes the application!
      if (fullscreen) {
        GraphicsEnvironment ge=null;
        GraphicsDevice gd=null;
        ge = GraphicsEnvironment.getLocalGraphicsEnvironment();  
        gd = ge.getDefaultScreenDevice();  
        if( gd.isFullScreenSupported() )
        {  
          gd.setFullScreenWindow(null);  
        } 
      }
      System.exit(0);
    }
    // ----------------- Add your own stuff here!
    //                 ...
    // ------------------------------------------
  }
}

class MouseInputHandler extends javax.swing.event.MouseInputAdapter {
  public void mouseDragged(MouseEvent e) {
    oglMouseX = e.getX();
    oglMouseY = e.getY();
    // ----------------- Add your own stuff here!
    //                 ...
    // ------------------------------------------
  }
  public void mouseMoved(MouseEvent e) {
    oglMouseX = e.getX();
    oglMouseY = e.getY();
    // ----------------- Add your own stuff here!
    //                 ...
    // ------------------------------------------
  }
  public void mousePressed(MouseEvent e) {
    oglMouseX = e.getX();
    oglMouseY = e.getY();
    mousePressed = true;
    // ----------------- Add your own stuff here!
    //                 ...
    // ------------------------------------------
  }
  public void mouseReleased(MouseEvent e) {
    oglMouseX = e.getX();
    oglMouseY = e.getY();
    mousePressed = false;
    // ----------------- Add your own stuff here!
    //                 ...
    // ------------------------------------------
  }
  public void mouseClicked(MouseEvent e) {
    oglMouseX = e.getX();
    oglMouseY = e.getY();
    // ----------------- Add your own stuff here!
    //                 ...
    // ------------------------------------------
  }
}