I have a ground tile for which I use a normal map, it reacts good when facing light, but looking in the Sun lamp direction kills the lightning. I'm using nodes, have a look at the pictures. Can somebody tell me what's wrong with my setup ? (connecting the texture normal output straight to the material gives the same result)
Normal mapping is a real pain in the node editor. In fact, it's an open bug. I seem to recall a few months ago someone mentioned/made a new node to fix this, but I haven't seen it in official builds yet.
The way around it I sometimes use (it's computationally expensive and a pain to set up), is to create a material for each normal map. Then you can take the normal output from the material and mix that together: Sorry for not mentioning this in my comment earlier.