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import java.io.IOException;
import org.lwjgl.LWJGLException;
import org.lwjgl.opengl.Display;
import org.lwjgl.opengl.DisplayMode;
import org.lwjgl.opengl.GL11;
import org.newdawn.slick.Color;
import org.newdawn.slick.opengl.Texture;
import org.newdawn.slick.opengl.TextureLoader;
import org.newdawn.slick.util.ResourceLoader;

public class TextureExample {
    
    /** The texture that will hold the image details */
    private Texture texture;
    
    
    /**
     * Start the example
     */
    public void start() {
        initGL(800,600);
        init();
        
        while (true) {
            GL11.glClear(GL11.GL_COLOR_BUFFER_BIT);
            render();
            
            Display.update();
            Display.sync(100);

            if (Display.isCloseRequested()) {
                Display.destroy();
                System.exit(0);
            }
        }
    }
    
    /**
     * Initialise the GL display
     * 
     * @param width The width of the display
     * @param height The height of the display
     */
    private void initGL(int width, int height) {
        try {
            Display.setDisplayMode(new DisplayMode(width,height));
            Display.create();
            Display.setVSyncEnabled(true);
        } catch (LWJGLException e) {
            e.printStackTrace();
            System.exit(0);
        }

        GL11.glEnable(GL11.GL_TEXTURE_2D);               
        
        GL11.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);          
        
            // enable alpha blending
            GL11.glEnable(GL11.GL_BLEND);
            GL11.glBlendFunc(GL11.GL_SRC_ALPHA, GL11.GL_ONE_MINUS_SRC_ALPHA);
        
            GL11.glViewport(0,0,width,height);
        GL11.glMatrixMode(GL11.GL_MODELVIEW);

        GL11.glMatrixMode(GL11.GL_PROJECTION);
        GL11.glLoadIdentity();
        GL11.glOrtho(0, width, height, 0, 1, -1);
        GL11.glMatrixMode(GL11.GL_MODELVIEW);
    }
    
    /**
     * Initialise resources
     */
    public void init() {
        
        try {
            // load texture from PNG file
            texture = TextureLoader.getTexture(
                "PNG", 
                ResourceLoader.getResourceAsStream(
                    "images/solid_red.png"));  // a 16x16 solid red png
        
            System.out.println("Texture loaded: "+texture);
            System.out.println(">> Image width: "+texture.getImageWidth());
            System.out.println(">> Image height: "+texture.getImageHeight());
            System.out.println(">> Texture width: "+texture.getTextureWidth());
            System.out.println(">> Texture height: "+texture.getTextureHeight());
            System.out.println(">> Texture ID: "+texture.getTextureID());
            System.out.println(">> Texture has alpha: " +texture.hasAlpha());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    /**
     * draw a quad with the image on it
     */
    public void render() {
        Color.white.bind();
        texture.bind(); // or GL11.glBind(texture.getTextureID());
        
        GL11.glBegin(GL11.GL_QUADS);
            GL11.glTexCoord2f(0,0);
            GL11.glVertex2f(100,100);
            GL11.glTexCoord2f(1,0);
            GL11.glVertex2f(100+texture.getTextureWidth(),100);
            GL11.glTexCoord2f(1,1);
            GL11.glVertex2f(100+texture.getTextureWidth(),100+texture.getTextureHeight());
            GL11.glTexCoord2f(0,1);
            GL11.glVertex2f(100,100+texture.getTextureHeight());
        GL11.glEnd();

        Color.white.bind();
        GL11.glBegin(GL11.GL_QUADS);
            GL11.glVertex2f(0, 0);
            GL11.glVertex2f(0, 100);
            GL11.glVertex2f(100, 100);
            GL11.glVertex2f(100, 0);
        GL11.glEnd();
    }
    
    /**
     * Main Class
     */
    public static void main(String[] argv) {
        TextureExample textureExample = new TextureExample();
        textureExample.start();
    }
}