Quick tutorial on Normal Maps.
Normal map is a vector map - direction vector map. Z is the UP, toward camera, Y is up, red is right. Well, that differ from a software really, Maya and Max use different Y directions (up <-> down), so basically a normal map looks like this:
Lets separate the color channels.
So, putting it simply, a normal map is a “pixel direction map”. So, the most blue pixel is facing the camera and won’t be more than 128 red and 128 green. Why? Cause we have a range of 255 bits on a texture channel. So, the FLAT is 128 red 128 green and 255 blue. So we can go right with 255 red or left with 0 red. Hopes that does make any sense to you. Anywa…
How to create a normal with ANY 3D software? I’ll use Max for demonstration. We have out object (I’ll use a simple noise plane for that) with a white material:
Then we add an ambient light, skylight not casting shadows and set it’s brightness to 0.5 white. This will add white 128 color to all of out channels:
Next we add a blue light from top with 0.5 power:
And lights from each direction, in 3D Studio is red+ on the X+, red- on the X-, green+ on the Y- and green- on the Y+ (green is negative in other words). I know that Maya uses Y for up not Z, so it’s gonna be different. No idea about blender
And t hen you render top view or orthographic camera:
You can use Displace to get the shape of your object from a texture or just model it.
But, it’s always better to just bake it using Render to texture, or crazy bump, or Nvidia tools, like guys before me said XD