// This code example is created for educational purpose
// by Thorsten Thormaehlen (contact: www.thormae.de).
// It is distributed without any warranty.

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import com.jogamp.opengl.*;
import com.jogamp.opengl.awt.GLCanvas;
import com.jogamp.opengl.util.FPSAnimator;
import static com.jogamp.opengl.GL.*;  
import static com.jogamp.opengl.GL2.*; 

class Renderer {

  public void init(GLAutoDrawable d) {}
  public void resize(GLAutoDrawable d, int width, int height) {
    GL2 gl = d.getGL().getGL2(); // get the OpenGL 2 graphics context
    gl.glViewport(0, 0, width, height);
  }
  public void display(GLAutoDrawable d) {
    GL2 gl = d.getGL().getGL2();  // get the OpenGL 2 graphics context
    gl.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
    gl.glClear(GL.GL_COLOR_BUFFER_BIT);
    gl.glLoadIdentity();
    gl.glOrtho(-1.0f, 1.0f, -1.0f, 1.0f, -1.0f, 1.0f);
    gl.glColor3f(1.0f, 1.0f, 1.0f);
    gl.glBegin(GL2.GL_TRIANGLES);
    gl.glVertex3f(-0.5f, -0.5f, 0.0f);
    gl.glVertex3f( 0.5f, -0.5f, 0.0f);
    gl.glVertex3f( 0.0f,  0.5f, 0.0f);
    gl.glEnd();
  }
  public void dispose(GLAutoDrawable d) {}
}


class MyGui extends JFrame implements GLEventListener{

  private Renderer renderer;
  
  public void createGUI() {
    setTitle("JoglFirstTriangle");
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   
    GLProfile glp = GLProfile.getDefault();
    GLCapabilities caps = new GLCapabilities(glp);
    GLCanvas canvas = new GLCanvas(caps);
    setSize(320, 320);
    getContentPane().add(canvas);
    final FPSAnimator ani = new FPSAnimator(canvas, 60, true);
    canvas.addGLEventListener(this);
    setVisible(true);
    renderer = new Renderer();
    ani.start();
  }

  @Override
  public void init(GLAutoDrawable d) { 
    renderer.init(d); 
  }

  @Override
  public void reshape(GLAutoDrawable d, int x, int y, int width, int height) {
    renderer.resize(d, width, height);
  }

  @Override
  public void display(GLAutoDrawable d) {
    renderer.display(d);
  }

  @Override
  public void dispose(GLAutoDrawable d) { 
    renderer.dispose(d);
  }
}

public class FirstTriangle {
  public static void main(String[] args) {
    System.setProperty("sun.java2d.uiScale", "1.0");
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
      public void run() {
        MyGui myGUI = new MyGui();
        myGUI.createGUI();
      }
    });
  }
}