The NORMAL map
Hera
Posts: 1,957
Hi!
Is there an easy explanation to what the normal map really does to a shader somewhere? I keep adding and removing those light-indigo pictures but can't really tell the difference.
Comments
Look here - http://en.wikipedia.org/wiki/Normal_mapping
First basic information: One of the most important calculations in 3D rendering is the angle between the light and the surface normal of the object. The surface normal is a vector which is perfectly perpendicular to the surface.
A normal map tells the rendering engine to deflect the surface normal in two dimensions. It is similar to a bump map in that it adds fine details to the render which aren't built into the underlying mesh. It is faster to render because it provides the changes to the angle of the surface normal directly to the rendering engine rather than asking the rendering engine to calculate the change (as bump and displacement does).
My Displaced Bumps and Is This Normal? blog articles discuss the different ways to add fine detail to surfaces. I also have some additional details in my DAZ Studio Displacement in Carrara 8 article.
If you can't see very much of a difference, there's probably a few potential causes.
First, if you are also using bump or displacement maps, and the normal map was designed to create the same details as those others, you won't see a change.
Second, the normal map may not be very good. Many quick normal maps are created by converting bump/displacement maps. Those have some real issues as they won't have as many fine details as maps created using the "proper" method.
Third, it could be that you need to ramp up the strength and/or min/max for the changes. In many cases fine detail maps like this which have been created with Poser in mind need to be adjusted in DAZ Studio because the implementations are slightly different.
Thanks tonnes guys! Very helpful!