Ashley - Yeah, I figured I should have added the correct image. I couldn't remember when I'd saved the image, so used another example.
As you said, it's probably the range, but you can see in this example that the light sprite is pretty far away from the walls.
Might it be possible to allow us to set the extrude distance ourselves? If I'm making a game for an iPad, I'll want it pretty large, but if I'm making a lower res game I want it smaller. If that's too tricky to add in, then not to worry. I imagine if it's off screen it won't cause many problems with processing anyway?
The shader for the next build... will I be able to use that without WebGL? Unfortunately I can't use WebGL for my next project.
I've just tried out your other method so I could better visualise it, and while I'm getting solid black shadows now where no light reaches, sadly it's still not the effect I want. Personally, I just want solid white for light, and solid black for shadow. I imagine I'll be able to do that next build.
This is with 34% opacity on each light. For some reason I'm getting pitch black shadows where there should be light... but in any case, I don't need transparent shadows, so it doesn't worry me too much. With this new effect you've created, will other people be able to get transparent lights? It doesn't sound like it, but in any case I intend on adding a fall off sprite that overlays the light source so it will slowly fall off into darkness.
Can you tell what they made this light system using? http://ncase.me/sight-and-light/ Is it HTML5? Flash? It appears to run great in a browser, and the code appears to be open source. I don't understand how this all works, so I'm not sure whether or not the same system is possible... but it appears to work with multiple light sources brilliantly!