MainWindow.java

package com.javamarcher.window;

import static org.lwjgl.glfw.Callbacks.glfwFreeCallbacks;
import static org.lwjgl.glfw.GLFW.glfwCreateWindow;
import static org.lwjgl.glfw.GLFW.glfwDestroyWindow;
import static org.lwjgl.glfw.GLFW.glfwGetPrimaryMonitor;
import static org.lwjgl.glfw.GLFW.glfwGetVideoMode;
import static org.lwjgl.glfw.GLFW.glfwInit;
import static org.lwjgl.glfw.GLFW.glfwMakeContextCurrent;
import static org.lwjgl.glfw.GLFW.glfwPollEvents;
import static org.lwjgl.glfw.GLFW.glfwSetErrorCallback;
import static org.lwjgl.glfw.GLFW.glfwSetWindowPos;
import static org.lwjgl.glfw.GLFW.glfwShowWindow;
import static org.lwjgl.glfw.GLFW.glfwSwapBuffers;
import static org.lwjgl.glfw.GLFW.glfwSwapInterval;
import static org.lwjgl.glfw.GLFW.glfwTerminate;
import static org.lwjgl.glfw.GLFW.glfwWindowHint;
import static org.lwjgl.glfw.GLFW.glfwWindowShouldClose;
import static org.lwjgl.opengl.GL11.GL_COLOR_BUFFER_BIT;
import static org.lwjgl.opengl.GL11.GL_DEPTH_BUFFER_BIT;
import static org.lwjgl.opengl.GL11.glClear;
import static org.lwjgl.opengl.GL11.glClearColor;
import static org.lwjgl.system.MemoryUtil.NULL;

import java.awt.event.WindowEvent;

import org.lwjgl.glfw.GLFW;
import org.lwjgl.glfw.GLFWErrorCallback;
import org.lwjgl.glfw.GLFWVidMode;
import org.lwjgl.opengl.GL;

import com.javamarcher.gamestate.MainState;
import com.javamarcher.gamestate.Notifiable;
import com.javamarcher.util.DeltaTimeUtil;

public class MainWindow {
	public static final int WIDTH = 1280;
	public static final int HEIGHT = 720;
	
	public static long WINDOW = 0;
	
	// The window handle
	private long window;
	
	// Game States
	private final Notifiable mainState = new MainState();
	
	// Options window
	private final OptionWindow optionWindow = new OptionWindow("Options");

	private static final DeltaTimeUtil deltaTimeUtil = new DeltaTimeUtil();
	
	public void run() {
		try {
			initialize();
			update();

			// Free the window callbacks and destroy the window
			glfwFreeCallbacks(window);
			glfwDestroyWindow(window);
		} finally {
			// Terminate GLFW and free the error callback
			glfwTerminate();
			glfwSetErrorCallback(null).free();
		}
	}

	private void initialize() {
		
		// Setup an error callback. The default implementation
		// will print the error message in System.err.
		GLFWErrorCallback.createPrint(System.err).set();

		// Initialize GLFW. Most GLFW functions will not work before doing this.
		if (!glfwInit())
			throw new IllegalStateException("Unable to initialize GLFW");

		// Configure our window
		glfwWindowHint(GLFW.GLFW_CONTEXT_VERSION_MAJOR, 3);
		glfwWindowHint(GLFW.GLFW_CONTEXT_VERSION_MINOR, 2);
		glfwWindowHint(GLFW.GLFW_OPENGL_PROFILE, GLFW.GLFW_OPENGL_CORE_PROFILE);
		glfwWindowHint(GLFW.GLFW_OPENGL_FORWARD_COMPAT, GLFW.GLFW_TRUE);

		// Create the window
		window = glfwCreateWindow(WIDTH, HEIGHT, "Java Marcher", NULL, NULL);
		WINDOW = window;
		if (window == NULL)
			throw new RuntimeException("Failed to create the GLFW window");

		// Get the resolution of the primary monitor
		GLFWVidMode vidmode = glfwGetVideoMode(glfwGetPrimaryMonitor());
		// Center our window
		glfwSetWindowPos(window, (vidmode.width() - WIDTH) / 2, (vidmode.height() - HEIGHT) / 2);

		// Make the OpenGL context current
		glfwMakeContextCurrent(window);
		// Enable v-sync
		glfwSwapInterval(1);

		// Make the window visible
		glfwShowWindow(window);
	}

	private void update() {
		GL.createCapabilities();
		initializeStates();
		glClearColor(0.4f, 0.4f, 0.4f, 0.0f);

		// Render until ESCAPE is pressed
		while (!glfwWindowShouldClose(window)) {
			glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

			updateStates();
			
			glfwSwapBuffers(window); // swap the color buffers
			
			// Poll for window events. The key callback above will only be
			// invoked during this call.
			glfwPollEvents();
		}
		
		optionWindow.dispatchEvent(new WindowEvent(optionWindow, WindowEvent.WINDOW_CLOSING));
		// Destroy if loop ends
		mainState.destroy();
	}
	
	private void initializeStates() {
		mainState.start();
	}
	
	private void updateStates() {
		deltaTimeUtil.calculateDeltaTime();
		mainState.update(deltaTimeUtil.getDeltaTime());
	}
	
	public static double getDeltaTime() {
		return deltaTimeUtil.getDeltaTime();
	}
	
	public static double getGlobalTime() {
		return deltaTimeUtil.getGlobalTime();
	}
}