Material/texture assistance
-
Hi all, I am in the process of getting my head around materials and textures. I see that when rendering to get "bump" I require a "normals" map. Since I am new to this, what is the difference between a "normal" and a " bump" map?
-
For Blender but it's must be the same for any 3D progs!
-
Bumps maps are black and white. With black representing the deepest indentation. Since there are only 2 colours bumps maps can only describe height in one direction.
Normal Maps use RGB, Red Green Blue, to describe height so the height direction can be multi-directional.
-
In short: normal maps are for game industry, bump maps are for 'still renders'.
Because in games, lights & objects move (real time lighting) and normal map handles such situations significantly better (more realistic). Here are ordinary maps to create a material in a game engine:
You can of course use normal maps in still renders but it's simply not necessary (and not efficient, because normal maps contain RGB values, thus file size is slightly bigger).
In addition to Blender manual that pilou shared, also take a look at Unity's manual that explains Normal map (Bump mapping) in depth with visual illustrations.
Easiest way to create a normal map: NormalMap-Online. But don't get me wrong, this is not the best way of creating normals (I strongly recommend checking this: How NOT To Make Normal Maps From Photos Or Images
-
The difference is mainly accuracy. Example: two pixels in a "ramp".
Bumpmap represents them as a stair.
Normalmap tells the engine wich direction they are facing, thus represents them as ramps.
Again normal maps are really worth if for game engines as people keep zooming in and normal maps work better, while at still rendering zooming in a lot isn't that usual.
Both still show artifacts at subtle bumpiness levels, but that is minimized with higher bit depth images like 16bit or 32bit images
Advertisement