OpenGL not rendering in fullscreen

[skyress3000]

I'm following the tutorials on the lwjgl wiki, but when I came to the last one I found this problem: my code won't render anything when it is fullscreen. It has no problem setting the display mode etc, but the blue square just won't show up. Here's my code:

import org.lwjgl.*;
import org.lwjgl.input.*;
import org.lwjgl.opengl.*;

public class OpenGLTesting {
	//position of quad
	float x = 400, y = 300;
	//angle of quad rotation
	float rotation = 0;

	//time at last frame
	long lastFrame;

	int fps;
	long lastFPS;

	boolean vsync;

	public void startYoFace() {
		try {
			Display.setDisplayMode(new DisplayMode(800,600));
			Display.create();
		} catch (LWJGLException e) {
			e.printStackTrace();
			System.exit(0);
		}

		initGL();
		getDelta();
		lastFPS = getTime();

		while(!Display.isCloseRequested()) {
			int delta = getDelta();

			update(delta);
			renderGL();

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

		Display.destroy();
	}

	public void update(int delta) {
		rotation += 0.15f * delta;

		if(Keyboard.isKeyDown(Keyboard.KEY_LEFT)) x -= 0.35f * delta;
		if(Keyboard.isKeyDown(Keyboard.KEY_RIGHT)) x += 0.35f * delta;

		if(Keyboard.isKeyDown(Keyboard.KEY_UP)) y += 0.35f * delta;
		if(Keyboard.isKeyDown(Keyboard.KEY_DOWN)) y -= 0.35f * delta;

		while(Keyboard.next()) {
			if(Keyboard.getEventKeyState()) {
				if(Keyboard.getEventKey() == Keyboard.KEY_F) {
					setDisplayMode(800, 600, !Display.isFullscreen());
				}
				else if(Keyboard.getEventKey() == Keyboard.KEY_V) {
					vsync = !vsync;
					Display.setVSyncEnabled(vsync);
				}
			}
		}

		//keep quad on the screen
		if(x < 0) x = 0;
		if(x > 800) x = 800;
		if(y < 0) y = 0;
		if(y > 600) y = 600;

		updateFPS();
	}

	public void setDisplayMode(int width, int height, boolean fullscreen) {
		if((Display.getDisplayMode().getWidth() == width) && (Display.getDisplayMode().getHeight() == height) && (Display.isFullscreen() == fullscreen)) return;

		try {
			DisplayMode targetDisplayMode = null;

			if (fullscreen) {
				DisplayMode[] modes = Display.getAvailableDisplayModes();
				int freq = 0;

				for(int i = 0; i < modes.length; i++) {
					DisplayMode current = modes[i];

					if((current.getWidth() == width) && (current.getHeight() == height)) {
						if((targetDisplayMode == null) || (current.getFrequency() >= freq)) {
							if((targetDisplayMode == null) || (current.getBitsPerPixel() > targetDisplayMode.getBitsPerPixel())) {
								targetDisplayMode = current;
								freq = targetDisplayMode.getFrequency();
							}
						}

						//if we've found a match for bpp and frequency against the
						//original display mode then it's probably bes to go for this one
						//since it's most likely compatible with the monitor
						if ((current.getBitsPerPixel() == Display.getDesktopDisplayMode().getBitsPerPixel()) && (current.getFrequency() == Display.getDesktopDisplayMode().getFrequency())) {
							targetDisplayMode = current;
							break;
						}
					}
				}
			} else {
				targetDisplayMode = new DisplayMode(width, height);
			}

			if (targetDisplayMode == null) {
				System.out.println("Failed to find value mode: " + width + "x" + height + " fs=" + fullscreen);
			}

			Display.setDisplayMode(targetDisplayMode);
			Display.setFullscreen(fullscreen);
		} catch(LWJGLException johnTheExceptionWhoIsABitchAndDeservesToDie) {
			System.out.println("Unable to setup mode: " + width + "x" + height + " fs=" + fullscreen + johnTheExceptionWhoIsABitchAndDeservesToDie);
		}
	}

	public int getDelta() {
		long time = getTime();
		int delta = (int) (time - lastFrame);
		lastFrame = time;

		return delta;
	}

	public long getTime() {
		return (Sys.getTime() * 1000) / Sys.getTimerResolution();
	}

	public void updateFPS() {
		if(getTime() - lastFPS > 1000) {
			Display.setTitle("FPS: " + fps);
			fps = 0;
			lastFPS += 1000;
		}
		fps++;
	}

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

	public void renderGL() {
		if(Display.isFullscreen()) System.out.println("fullscreen...");
		GL11.glClear(GL11.GL_COLOR_BUFFER_BIT | GL11.GL_DEPTH_BUFFER_BIT);

		GL11.glColor3f(0.5f, 0.5f, 1.0f);

		GL11.glPushMatrix();
		GL11.glTranslatef(x, y, 0);
		GL11.glRotatef(rotation, 0f, 0f, 1f);
		GL11.glTranslatef(-x, -y, 0);

		GL11.glBegin(GL11.GL_QUADS);
		GL11.glVertex2f(x - 50, y - 50);
		GL11.glVertex2f(x + 50, y - 50);
		GL11.glVertex2f(x + 50, y + 50);
		GL11.glVertex2f(x - 50, y + 50);
		GL11.glEnd();
		GL11.glPopMatrix();
	}

	public static void main(String[] args) {
		OpenGLTesting test = new OpenGLTesting();
		test.startYoFace();
	}
}

[Kai]

Try a glViewport(0, 0, 800, 600); at the very beginning of your renderGL method. Whenever I played with resizing windows in whatever window manager I used, mostly I saw nothing because of an ill defined GL viewport transform.