View Full Version : Normal Mapping Mechanical Stuff

10 October 2008, 06:54 AM
I'm familiar with the normal mapping workflow. Make a high poly version, make a low poly version, use one to make the normalmap texture for the other. No mystery. Lots of UV mapping in between.

Here's where I'm fuzzy on the whole concept, though. I know exactly how to handle it for a model of a character that's all one big mesh. I have positively no clue when it comes to doing detailed machinery, where the high poly's detail comes from a ton of separate parts and meshes not present on the low-poly model. I can't even begin to wrap my head around it.

For example, take the following image:

It's nothing fancy. It's a beveled cube with a bunch of cylenders stuck in the sides for "rivets." I literally just have them penetrating into the cube because it's a very efficient way of putting together the model. Suppose I wanted to generate a normalmap (I realize straight cylenders probably aren't the best things to do to demo it, but bear with me here) and map that detail onto just a regular beveled cube. How the heck does this work? Someone help me out here, I'm royally confused. It's so much easier to think of doing this for organic stuff where all the geometry exists on both models...

10 October 2008, 07:24 AM
After some digging (I really ought to dig first before posting in forums) I discovered it doesn't actually matter whether the high-res object's composed of dozens of different meshes or not, so long as the two objects are similar enough and the low-res is UV-mapped properly you can normal-map it. Fascinating.

10 October 2008, 08:20 AM
He's right,
It doesnt really matter if the high poly version consists of multiple objects.When you set a projection modifier(in 3dsmax this is) on the low poly(correctly UV mapped),and place the high poly in exactly the same position,adjust the cage,then it will catch the normal of the whole object.
I have done dozens of normals of multi objects,and i have to say,the projection modifier in 3dsmax,does a fabulous job at it..
-Create low poly version
-Create high poly version
(or the other way around,whatever suits you best)
-Be sure to center both objects to 0,0,0
-Properly uv-map the low poly version
-Place the high poly in the exact same position as the low poly version
-Add a Projection Modifier to the low poly version
-In the stack,click Cage
-Then pick a reference object,by clicking pick list(in this case the high poly version)
-Adjust the cage to fine tune it(click "shaded" for a better reference on what the cage is covering,and play around with the "percent" and "amount" settings
-Then hit render to texture,and tick projection mapping Enabled.
-On the mapping coordinates section be sure you use the EXISTING Channel!(because you dont want Max to screw up your uv's)
-Then add a normalsmap in the output dialog,choose bump as a taget map slot
and be sure to tick "Output into Normalbump" in the" Element unique settings"
-There ya go,...Done,render to texture ,and there's your normalmap.

Oh and add lights to your discretion,...

10 October 2008, 10:42 AM
Ooh. Thank you for the detailed reply! That informative even beyond my inquiries. :) I got my initial impressions of normal mapping from my experiences with Zbrush, so that's where I got mixed up on the whole process. I'll start digging around 3DS Max for the normal mapping stuff!

10 October 2008, 07:22 PM
you can also try this free tool

10 October 2008, 10:09 PM
You know, I've actually heard good things about it. I may just do that. :)

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