Thank you guys. The goal I want to achieve, is to show the gameplay of a 2D game that I'd like to develop in future. So the soft-edged shadows vs. hard edged, is not a problem. For a quick demo, of course it should be more simpler by simulating how the shadow casting works, instead of programming it...

Hi everyone,
I'd like to know the best strategy (if there is one) to get a 2D casting shadows effect, like this:
https://www.youtube.com/watch?v=7BBDP43SXkA
https://www.youtube.com/watch?v=UN1pyFVRed4