AOC from normal map?

jordan.kocon

Hey all, I have another question for all you poly counters. So I started making a high poly model, and I understand how to bake the normals out, but how can I get an ambient occlusion map from the high as well? In my case I am doing an air conditioning unit, and I was wondering if I normal map the grate and fan blades onto the front how I could get all that detail in an ambient occlusion map, because obviously the AOC from the low poly would just be a flat face. (I am modeling the high poly in softimage first, then bringing it into zbrush for finer details if this helps)

Thanks in advance!

jordan.kocon

thanks for the quick reply perna. So xNormal can look at the uv's of my low poly, and make an ambient occlusion map based on my high poly onto the uv's? I've never used xNormal so I have no idea what exactly it does. I will definitely check it out though

cryrid

To do that in Softimage you can use Ultimapper, the same thing used to create normal maps from highpoly meshes (select the low poly and choose Get>Property>Ultimapper. There you can select the hi-res target and the maps you wish to bake, Ambient Occlusion is on the list of maps you can chose). You can change the settings for AO in the Advanced Tab.

If you were baking the normal map in zbrush and wanted to use that for the AO as well, download the MultiMap Exporter plugin. That is capable of doing the AO. Otherwise you could probably duplicate the tool, fill it 100% with pure black polypaint, use the mask subpallete to mask by ambient occlusion, and then fill it with white. Then create a new texture from that polypaint.

Xnormal is also a great option though, so don't let this post hinder you from trying it out.

jordan.kocon

Cryid: Oooo ultimapper does ambient occlusion too, well I feel like an IDIOT never used it for anything other than normal maps. I'll give that a try, but will also try out Xnormal. Thanks for that

Giometric

^ Beaten :P But to answer your question, yes, both Ultimapper in Softimage and xNormal will bake Ambient Occlusion from your hi-poly source model to the UVs of your low-poly model (pretty much how any hi-res to low-res baking tool works in general). Definitely give both of those a try, sometimes you'll find you can coax one or the other into giving you a nicer result. Note that for Ultimapper, if your hi poly model consists of more than one object you'll need to create a group containing all those objects, and use that as your hi-poly source.

Wonkey

Not sure if this will help you, but Today, Eat3d release a free video overview of xNormal

http://eat3d.com/free/xnormal_overview