Super Fast Soft Shadow system for Unity:
We're the authors of Chipmunk2D physics engine and Cocos2D-SpriteBuilder maintainers. We recently rewrote the Cocos2D renderer and added lighting effects, and now we're back to writing Unity plugins!
Shadow mask generation occurs in a single pass - it doesn't use expensive image filters or pixel shaders to soften the shadows. This means it runs great on mobile!
Physically realistic penumbra, umbra, and antumbra rendering is based on configurable light sizes. This produces accurate rendering when the light source is larger than the objects casting the shadows.