So, here's the capx
dropbox.com/s/uywy4s3y3adkjmw/pixelshadowcaster.capx
I'm using line of sight to object to change the ground tile brightness value to 100, and invert line of sight to object to change it to 70.
What I'm trying to figure out is if there is a more performance-effective way of doing this at a pixel level or how to optimize it if I want to use it at a very large scale?
Edit: A gif
<img src="http://i.imgur.com/Jg1ZSj7.gif" border="0" />
As you can see here the framerate is only about 25.