GLRenderer.java

package org.yourorghere;

import javax.media.opengl.DebugGL2;
import javax.media.opengl.GL2;
import javax.media.opengl.GLAutoDrawable;
import javax.media.opengl.GLEventListener;
import javax.media.opengl.glu.GLU;


/**
 * GLRenderer.java <BR>
 * author: Brian Paul (converted to Java by Ron Cemer and Sven Goethel) <P>
 *
 * This version is equal to Brian Paul's version 1.2 1999/10/21
 */
public class GLRenderer implements GLEventListener {

    public void init(GLAutoDrawable drawable) {
        // Use debug pipeline, all OpenGL error codes will be automatically
        // converted to GLExceptions as soon as they appear
        drawable.setGL(new DebugGL2(drawable.getGL().getGL2()));

        GL2 gl = drawable.getGL().getGL2();
        System.err.println("INIT GL IS: " + gl.getClass().getName());

        // Enable VSync
        gl.setSwapInterval(1);

        // Setup the drawing area and shading mode
        gl.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
        gl.glShadeModel(GL2.GL_SMOOTH); // try setting this to GL_FLAT and see what happens.
    }

    public void reshape(GLAutoDrawable drawable, int x, int y, int width, int height) {
        GL2 gl = drawable.getGL().getGL2();
        GLU glu = new GLU();

        if (height <= 0) { // avoid a divide by zero error!
            height = 1;
        }
        final float h = (float) width / (float) height;
        gl.glViewport(0, 0, width, height);
        gl.glMatrixMode(GL2.GL_PROJECTION);
        gl.glLoadIdentity();
        glu.gluPerspective(45.0f, h, 1.0, 20.0);
        gl.glMatrixMode(GL2.GL_MODELVIEW);
        gl.glLoadIdentity();
    }

    public void display(GLAutoDrawable drawable) {
        GL2 gl = drawable.getGL().getGL2();

        // Clear the drawing area
        gl.glClear(GL2.GL_COLOR_BUFFER_BIT | GL2.GL_DEPTH_BUFFER_BIT);
        // Reset the current matrix to the "identity"
        gl.glLoadIdentity();

        // Move the "drawing cursor" around
        gl.glTranslatef(-1.5f, 0.0f, -6.0f);

        // Drawing Using Triangles
        gl.glBegin(GL2.GL_TRIANGLES);
            gl.glColor3f(1.0f, 0.0f, 0.0f);    // Set the current drawing color to red
            gl.glVertex3f(0.0f, 1.0f, 0.0f);   // Top
            gl.glColor3f(0.0f, 1.0f, 0.0f);    // Set the current drawing color to green
            gl.glVertex3f(-1.0f, -1.0f, 0.0f); // Bottom Left
            gl.glColor3f(0.0f, 0.0f, 1.0f);    // Set the current drawing color to blue
            gl.glVertex3f(1.0f, -1.0f, 0.0f);  // Bottom Right
        // Finished Drawing The Triangle
        gl.glEnd();

        // Move the "drawing cursor" to another position
        gl.glTranslatef(3.0f, 0.0f, 0.0f);
        // Draw A Quad
        gl.glBegin(GL2.GL_QUADS);
            gl.glColor3f(0.5f, 0.5f, 1.0f);    // Set the current drawing color to light blue
            gl.glVertex3f(-1.0f, 1.0f, 0.0f);  // Top Left
            gl.glVertex3f(1.0f, 1.0f, 0.0f);   // Top Right
            gl.glVertex3f(1.0f, -1.0f, 0.0f);  // Bottom Right
            gl.glVertex3f(-1.0f, -1.0f, 0.0f); // Bottom Left
        // Done Drawing The Quad
        gl.glEnd();

    }

    public void dispose(GLAutoDrawable arg0) {
    }
}