Light Effects (Multiple Lights!)

This works just like the other one, but it now supports multiple lights at once and comes in a Drawing-like interface (that's what I used to make that screenshot). You can also choose the background image, so you can use it to add speciall effects to ANY image you have, using multiple colors at the same time! Many thanks to Simon Price -- I took the function that extracts the RGBs without errors from one of his submissions!