Vertex Arrays Example

package com.quew8.testapp;

import java.nio.FloatBuffer;
import java.nio.IntBuffer;
import org.lwjgl.BufferUtils;
import org.lwjgl.LWJGLException;
import org.lwjgl.opengl.Display;
import org.lwjgl.opengl.DisplayMode;

import static org.lwjgl.opengl.GL11.*;
import org.lwjgl.util.glu.GLU;

/**
 *
 * @author Quew8
 */
public class TestApplication {

    public static void init() throws LWJGLException {
        Display.setDisplayMode(new DisplayMode(800, 600));
        Display.setTitle("Test App");
        Display.create();

        glClearColor(1, 0, 0, 0);
    }

    public static void loop() {
        int error;

        FloatBuffer vertexBuffer = BufferUtils.createFloatBuffer(12 * 2);
        vertexBuffer.put(new float[] {
            25, 45, //0
            45, 65, //1
            65, 45, //2
            45, 25, //3
            25, 85, //4
            45, 105, //5
            65, 85, //6
            85, 105, //7
            105, 85, //8
            85, 65, //9
            105, 45, //10
            85, 25, //11
        });
        vertexBuffer.flip();

        FloatBuffer colourBuffer = BufferUtils.createFloatBuffer(12 * 3);
        colourBuffer.put(new float[] {
            0, 1, 0, //0
            0, 0, 1, //1
            1, 0, 1, //2
            0, 1, 0, //3
            0, 1, 0, //4
            0, 1, 0, //5
            1, 0, 1, //6
            0, 1, 0, //7
            0, 1, 0, //8
            0, 0, 1, //9
            0, 1, 0, //10
            0, 1, 0, //11
        });
        colourBuffer.flip();

        IntBuffer indexBuffer = BufferUtils.createIntBuffer(20);
        indexBuffer.put(new int[] {
            0, 1, 2, 3, // Lower Left
            4, 5, 6, 1, // Upper Left
            7, 8, 9, 6, // Upper Right
            10, 11, 2, 9, // Lower Right
            1, 6, 9, 2, // Middle
        });
        indexBuffer.flip();

        while(!Display.isCloseRequested()) {
            glViewport(0, 0, 800, 600);

            glClear(GL_COLOR_BUFFER_BIT);

            glMatrixMode(GL_PROJECTION);
            glLoadIdentity();
            glOrtho(0, 140, 0, 140, -1, 1);

            glMatrixMode(GL_MODELVIEW);
            glLoadIdentity();

            glEnableClientState(GL_VERTEX_ARRAY);
            glEnableClientState(GL_COLOR_ARRAY);

            glVertexPointer(2, 8, vertexBuffer);
            glColorPointer(3, 12, colourBuffer);

            glDrawElements(GL_QUADS, indexBuffer);

            glDisableClientState(GL_COLOR_ARRAY);
            glDisableClientState(GL_VERTEX_ARRAY);

            if( (error = glGetError()) != GL_NO_ERROR) {
                System.err.print(GLU.gluGetString(error));
                throw new RuntimeException("Something Bad Has Happened");
            }

            Display.update();
            Display.sync(60);
        }
    }

    public static void deinit() {
        Display.destroy();
    }

    public static void main(String[] args) throws LWJGLException {
        TestApplication.init();
        TestApplication.loop();
        TestApplication.deinit();
    }

}