Game.java

package me.willchill.game;

import me.willchill.game.entity.Entity;
import me.willchill.game.input.GameKeyboard;

import org.lwjgl.LWJGLException;
import org.lwjgl.opengl.Display;
import org.lwjgl.opengl.DisplayMode;
import org.lwjgl.opengl.GL11;

public class Game{

    private GameKeyboard keyboard;
    private String gameStats = " ";
    private Entity player;

    public Game(){
        keyboard = new GameKeyboard();
    }

    private void start(){

        try{
            Display.setDisplayMode(new DisplayMode(800,600));
            Display.create();
            Display.setTitle("Game");
            Display.setVSyncEnabled(true);
        } catch (LWJGLException e){
            e.printStackTrace();
            System.exit(0);
        }

        initGL();
        player = new Entity("/res/player.png", 400, 300);

        long lastTime = System.nanoTime();
        long timer = System.currentTimeMillis();
        double ns = 1000000000.0 / 60.0;
        double delta = 0;
        int frames = 0;
        int updates = 0;


        while(!Display.isCloseRequested()){

            long now = System.nanoTime();
            delta += (now - lastTime) / ns;
            lastTime = now;

            while(delta >= 1){
                update();
                updates++;
                delta--;
            }

            frames++;

            if(System.currentTimeMillis() - timer > 1000){
                timer += 1000;
                gameStats = "FPS: " + frames + ", UPS: " + updates;
                Display.setTitle("Game " + gameStats);
                System.out.println(gameStats);
                updates = 0;
                frames = 0;
            }

            render();
            Display.update();
        }

        Display.destroy();
    }

    private void render(){
        GL11.glClear(GL11.GL_COLOR_BUFFER_BIT|GL11.GL_DEPTH_BUFFER_BIT);

        GL11.glBegin(GL11.GL_QUADS);
            GL11.glVertex2f(player.x, player.y ); //Top-left
            GL11.glVertex2f(player.x + player.texture.getTextureWidth(), player.y);//Top-right
            GL11.glVertex2f(player.x + player.texture.getTextureWidth(), player.y + player.texture.getTextureHeight());//Bottom-right
            GL11.glVertex2f(player.x, player.y + player.texture.getTextureHeight());//Bottom-left
        GL11.glEnd();
    }

    private void update() {
        keyboard.pollInput();
    }

    public void initGL() {
        GL11.glMatrixMode(GL11.GL_PROJECTION);
        GL11.glLoadIdentity();
        GL11.glOrtho(0, 800, 0, 600, 1, -1);
        GL11.glMatrixMode(GL11.GL_MODELVIEW);
        GL11.glEnable(GL11.GL_TEXTURE_2D);
    }

    public static void main(String args[]){
        Game game = new Game();
        game.start();
    }
}