It's not very hard, I've got a build that has something like this, but the impact in-game is terrible, the game drops to 1 FPS when lots of lights are displayed, I'm not sure if the way I got it implemented would be part of the problem thought

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I remember I talked about this with Janis time ago and he gave me reasons of why it impacted the performance, so until a better way for making REAL dynamic lights is found, I guess possibilities for real shadows aren't much

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