Using nodes to generate normal maps, what's wrong?

Support Basics & Interface
1

Hi, I am trying to understand with clarity the way nodes actually work, so I decided to repeat the CREATION of a normal map image, using the node compositor. Well, my test was almost ok, but the colours are not so “bright” (yeah, I am not native english-speaker).

Well, here is the file:

http://www.bellera.org/blenderfor/users/jedihe/Nodes%20Normal%20Map.zip

there are two scenes, one has the classic normal map (using typical blend texture) and the other has my attempt to do nodes-normal-map-generation…

Thanks in advance!!

jedihe

P.D. I would appreciate some info (not necessarily easy to understand, I like mathematics ; ) ) about the way nodes work.

2

On your classic method, I’ve read from this tutorial that it’s good to offset your blue channel in x by -0.500 and to set it’s size to 2.00 in Map Input.

Makes it less “bright” I think.

3

I must say that I don’t know why it’s good to do it this way. I read about it on the original release log of Blender: http://www.blender.org/cms/Normal_Maps.491.0.html

Since normals all point towards a viewer, negative values are not stored. In Blender we store a full blue range, although some other implementations also map blue colors (128-255) to (0.0 - 1.0). The latter convention is used in “Doom 3” for example.

I only duplicated this bit of info, because creating normal maps is very hype in the game industry nowadays, and because Doom 3 engine is now GPL. But I seldom use this technique myself.

Cheers,

4

Thanks a lot, I will keep testing, I didn’t know the info on negative values and size settings… I hope I will get the map as the classic one.

jedihe