View Full Version : How to go about making a normal map with mudbox?

04 April 2007, 10:39 AM
Hey guys im trying to make a normal map for a model i have. It is not big by any standards, but as a biped it has alot going on from a head, torso, arms and legs.

Now i want to make normal maps for these, however i have problems. If i try to import the whole model to work on, it crahses when i try to sub divided by 2, which i could understand, but i also tried to save individual sections of the biped and sculpt in mudbox, and i would subdivided by 7 or even 8 and the poly count would go way through the roof, compared to the biped.
The only problem with sectioning it up is there are problems with the seams as they dont match up.

I was wondering if anyone could give me a few tips to go about this?! Thank you.

04 April 2007, 12:37 PM
create the normal maps from the low poly mesh that is not cut up.

Composite the different normal maps using Overlay blend mode in photoshop,,,and you may still have to retouch trouble areas.

04 April 2007, 05:25 PM
ok so it is important to make sure the whole mesh is in one. It's weird it may be my computer but it ust crashes. Is there an alternative format i can export into mudbox other then obj?

The overlay part i was doing, but i guess taking the time to retouch is probably the best way. Abit of hard graft as it were.

Any other suggestions would be great.

04 April 2007, 10:20 AM
normal calculations get a bit dodgy at extreme angles on low polys. You only compound this near borders where there is no geometry which is why I recommend baking from the entire mesh so that the normals will have some information for the calculations.

I recommend smoothing the low poly geometry 1x before hand for better results.

If your computer is crashing you might be running out of memory to do the calculations. Try baking the normal maps at minimum settings, at low resolutions first...and then work your way up to find the limit.

04 April 2007, 10:29 AM
Those are some great tips thank you!

Memory doesnt seem to be an issue, as i have 2GB worth. And i can really go up with the increase of polys using a section. But i will hold it into consideration.

The problem i am having is it just keeps crashing, everytime i try to sub divided to the second level. So i really need to try ans fix that. I reallly need to import the whole model to really get it to work, that is for sure.

04 April 2007, 10:41 AM
sounds like a memory issue if you cannot subdivide past level 2.

The hiRes geometry you can do in sections (see my dominance war entry). Just make sure the lo-res geometry is the entire mesh.

secondly, when baking normals make sure the quality settings are the lowest. These settings actually subdivide the mesh in addition to current levels when calculating normals...which is why you may have memory issues that crash mudbox.

04 April 2007, 12:11 PM
2 BYTS, thanks for the help i really appreciate it.

Well tell me what you think after i show you the comparisons, because i would understand if i had a real hi poly mesh, but when i sub divided by level 2 it hits no where near my other subdivisions.

this is a section of the model, notice the memory used and the levels i have gone up.

This is the problem file, and well it keeps doing this. Notice how one the first subdivision polys and memory use is really still low. It crashes 90% of calculation when trying to subdivided to level 2.

If anyone has had any problems like this, or know of any update fixes, or maybe you might be right my memory is just lacking.

Thanks again 2Bytes

04 April 2007, 12:29 PM
2Bytes i got it to work, seemed to be a file issue. Basically after a few attemps. i merged my file into a new file. and made sure there was nothing hidden, so a nice fresh file and well it worked, so thanks so much for your help. Really appreciate it!

04 April 2007, 07:02 PM
that was going to be my next suggestion. Do not subdivide a mesh with hidden geometry, or geometry removed from memory.

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