Virtual Lighting and DMX

I'm new to arduino, but I'd like to explore controlling lights with DMX. I have a DMX shield and an LED par, but I'd like to start developing patterns and animations without needing to initially purchase hundreads of LEDs/lights and DMX devices during my prototyping stages.

I'm looking at controlling RGB LED nodes on a 16x16 grid array. Does anyone know of a neat way of virtualising this in software with the DMX library? ie create a virtual image that listens to the DMX code? I was thinking perhaps there was a way to do this in processing/OF or maybe even quartz composer.

I'm still a beginner in processing and haven't really moved beyond the basics, but be great if anyone can highlight any pitfalls of such a thing. I've googled and found nothing unfortunately other than lighting design software.

ta.