Importance of Normal Maps for Arch Viz

[jrboddie1]

I know this is a very noobish question but I am hoping to learn something from the more experienced artists here.

The question is basically, how important is using normal maps for materials in architectural visualization? I understand what normal maps do and how they can provide visual detail without additional mesh complexity. I have also read that pros say that every object should always have diffuse, normal and specular maps in order to achieve photo real results.

On the other hand, I see that the 0.1.1 Yafaray does not support tangent normal maps. I know the next release will support it. I may be wrong, but Luxworks may not support normal maps at this time either. So I don't understand why this feature does not seem to have a very high priority.

The only conclusion that I can come up with is that artists use normal maps primarily for games and animation but for photo real architectural visualization, details are done with higher complexity meshes.

My project is a large external scene with many rock walls. I plan to make stills and some animation walk thrus. My dilemma is whether to use displacement in blender--with sky high poly counts or wait for 0.1.2 and a working normal map function.

So please educate me about the virtues (or lack thereof) of normal maps in arch viz.

[subcomandante]

hi jrboddie1,
as you said tanget space normal maps will be supported on next release (and they are already supported in current experimental code).

They are only useful for small details (small against whole mesh size) like bump map.

[jrboddie1]

Isn't there a problem with the intensity control for normal maps in the experimental? Or is that only for bump map?

In the context of arch viz, do people generally just use bump maps (instead of tangent space normal maps) to get the fine detail?

For the face of a rock wall would you use a high poly displace or tangent normal?

I am now thinking that I should create a low res and high res model for each major object in my scene.

[subcomandante]

Current experimental version has too sensitive bump map, not normal map.

Yes, bump maps are used more than normal maps but normal maps are more detailed.

Normal or bump map are weak and I'd use displacement map for details but they could reach the goal if you are looking for small details. So I would use normal/bump map *and* displacement map for a rock wall (displacement for major mesh shape and bump/normal for very little details like wrinkle surface.