I am currently working on developing a 2D tile based game, similar to the game 'Terraria'. We have the base tile and chunk engine working and are now looking to implement lighting. Instead of the tile based lighting that terraria uses, I want to implement point lights for torches, etc.

I have seen Catalin Zima’s shader based shadows, and this would be perfect for the torches (point lights). My problem here is that the tiles on the surface of the world need to be illuminated, doing this by a big point light is firstly extremely expensive, but also doesn't look right.

What I need help with (overall) is...

1. To have a surface that is illuminated regardless of torches, etc.
2. To also have point lights, or smooth tile lighting similar to Catalin Zima’s shader based shadows.

Looking forward to your replies. Any ideas are appreciated.