How can I make a loading screen?

[zorg]

It shows it for a split second because i removed the sleep command; with it, the image would indeed show for 3 seconds, after the initial flash and transparency, but again, that's irrelevant. And actually, every löve program behaves like this for me when the window is created.

[pgimeno]

OK, thanks for the clarification. Then it's an unavoidable initialization glitch, but the loading screen still works the way it's designed to work.