[Lutger]

The way Arc deals with setting the screen resolution is a little confusing to me. You can set the width and height with io.window.open, however arc then still uses virtual 800 x 600 virtual resolution. This is not what I expected, so i thought this was some mistake which I 'fixed'.
Imho, a virtual resolution should be clamped to 0.0f x 1.0f as is common with opengl, 800 x 600 looks too much like a real resolution. My suggestion would be to either have a 0.0f x 1.0f resolution or a resolution defined by the user. Whatever you do, some mention of this would be nice or maybe I didn't see it?

[clayasaurus]

I'll give the user the ability to define the virtual resolution.