1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99

package org.lwjgltutorial.chapter2;

import static org.lwjgl.opengl.GL11.GL_LINE_LOOP;
import static org.lwjgl.opengl.GL11.glBegin;
import static org.lwjgl.opengl.GL11.glEnd;
import static org.lwjgl.opengl.GL11.glFlush;
import static org.lwjgl.opengl.GL11.glVertex3f;
import static org.lwjgl.opengl.GL11.*;
import org.lwjgl.LWJGLException;
import org.lwjgl.opengl.Display;
import org.lwjgl.opengl.DisplayMode;

public class ProperSquare {
	
	private static final int WINDOW_HEIGHT = 600;
	private static final int WINDOW_WIDTH = 800;

	public ProperSquare(){
		init();
	}
	
	private void init() {
		// find out what the current bits per pixel of the desktop is
		int currentBpp = Display.getDisplayMode().getBitsPerPixel();
		// find a display mode at 800x600
		try {
			DisplayMode mode = findDisplayMode(WINDOW_WIDTH, WINDOW_HEIGHT,
					currentBpp);
			Display.setDisplayMode(mode);
			Display.setFullscreen(false);
			Display.setTitle("Proper Square");
			Display.create();
		} catch (LWJGLException e) {
			e.printStackTrace();
		}
		
		glMatrixMode(GL_PROJECTION);
		glLoadIdentity();
		double aspectRatio = (double)WINDOW_WIDTH/WINDOW_HEIGHT;
		glOrtho(aspectRatio,- aspectRatio, -1.0d, 1.0d, 1.0d, -1.0d);
		glMatrixMode(GL_MODELVIEW);
		glLoadIdentity();
	}
	
	private void loop() {
		render();
		// update window.
		Display.update();
		// wait for close
		while(!Display.isCloseRequested()){
			try {
				Thread.sleep(100);
			} catch (InterruptedException e) {
				e.printStackTrace();
			}		
		}
		Display.destroy();
	}

	private void render() {
		// draw the square
		glBegin(GL_LINE_LOOP);
		glVertex3f(-0.5f, -0.5f, 0.5f);
		glVertex3f(-0.5f, 0.5f, 0.5f);
		glVertex3f(0.5f, 0.5f, 0.5f);
		glVertex3f(0.5f, -0.5f, 0.5f);
		glEnd();
		
		// flush any commands that are still hanging about.
		glFlush();
	}


	private DisplayMode findDisplayMode(int width, int height, int bpp) throws LWJGLException {
		DisplayMode[] modes = Display.getAvailableDisplayModes();
		DisplayMode mode = null;

		for (int i=0;i<modes.length;i++) {
			if ((modes[i].getBitsPerPixel() == bpp) || (mode == null)) {
				if ((modes[i].getWidth() == width) && (modes[i].getHeight() == height)) {
					mode = modes[i];
				}
			}
		}
		
		return mode;
	}

	public static void main(String[] args) throws InterruptedException{
		
		ProperSquare square = new ProperSquare();
		square.loop();
		
	}


	
	
}