CAD to Poly - Texturing Question

Playdo

I have a CAD file that I need to texture. The problem is that when I import the CAD file into Max and convert to polys, the resulting geometry is very dense and messy (lots of stretched triangles and poles), which causes a lot of problems when uv unwrapping.

Is it usually better to remodel the geometry or to try and clean up the existing geometry when the uv mapping needs to be precise? I'm looking to do more product renderings in future so would appreciate experienced answers to this problem (I know that Lamont does this type of work :poly121:).

Playdo

Anyone?

Also, I've been looking at retopologizing recently. From what I gather, you create a lower poly mesh by snapping the new surface over the underlying high poly one. What if I wanted to do something similar with a HP sub-d model over a CAD model. Is there a way (as the smoothing changes the shape)?

Hoopla!

not sure bro, but have you tried the surface modifier? i think cad comes in like splines right?

can you post up some pics and give maybe a little more detailed explanation of a specific example of the problem? im guessing around a lot trying to figure out where the density problems would be. :shrug:

Playdo

Not sure if you can extract cad splines to model off of, I'll have to check. Here's a pic of what I mean. It was just horrible to try unwrapping. Edge loops don't work. The whole geometry needed a massive clean up (perhaps making all quads), that it seems easier to remodel.

renderhjs

a few ideas:

• use the slice modifier several times to break down those long stretchy triangles so that flattening and relaxing UV shells works more predictable. Once everything is relaxed you can simply select those slice loops and remove them again using ctrl+backspace.
• MaxRetopo is a nice free maxscript that lets you retopo a mesh:
  http://www.scriptspot.com/3ds-max/scripts/max-retopo
• Try a unwrapping tool such as Headus UVlayout with edge / pin rule sets to force even a messy mesh like that to unwrap reasonable.

Playdo

Thanks Render. I've begun remodeling it but I'll bare those suggestions in mind.