This is cool, i have these two humanoids in Blender, and both react the same to light: depending where the light is, one side gets iluminated and the other gets dark
The cool thing is, that one is a proper model, and the other is a mere image in a plane.
Why is this cool? With this technique you can have things in the background reacting in detail with the ambient light with just a fraction of the geometry needed.
@anondyne it's not exactly relighting any image, you still have to have the model to do this.
This is another example, the left one is the actual model and the right one is a plane with an image and a normal map created from the model. Like i said this is useful to add detail to scenes without using too much geometry.
It's not hard to do, i don't remember exactly where i saw the indications to do this, as soon as i find i will reply to this post.
@hideki What! How? Didn’t realize blender could relight images. Is this a shader/node of some sort?