will help you I would suggest: copy the object, move it in the opposite direction of the light source and use its distance as a weight, turn it totally black, blur it using the light source's distance as a weight, too, put it behind the object, lower the alpha if you want. ????? profit.
seems to work fine I have to write a faster canvas in wpf for my upcoming project. The canvas will be similar to adobe photoshop canvas. It should have layers and objects and also direct drawing methods. , I suggest you use QT. :)
Curve making UI that imitates that of Powerpoint and Photoshop in C#