Author Topic: idea: masking parts of complex geometry with simple geometry  (Read 292 times)

0 Members and 1 Guest are viewing this topic.

Offline RRIS

  • Full Member
  • ***
  • Posts: 226
  • Renze Rispens - industrial designer
idea: masking parts of complex geometry with simple geometry
« on: January 17, 2019, 06:45:06 am »
I'm working on a heavy 3D scanned model of a person sitting behind a steering wheel and of course it turns out the hands are too close to fit the wheel I have here. I wanted to split the geometry and move one of the arms to the correct position, but the model is too heavy and keeps crashing Keyshot.

A coworker of mine had the idea it would be cool to be able to place simple geometry around the part of the scan that you need that would basically render everything of the scan outside that geometry invisible.
That way I could place two cubes around the hands/arms, duplicate the model and move each arm to the correct position.

I know you could achieve something similar with an opacity map, however, this model has a complex UV-mapped material and this would be a daunting task to say the least.

Maybe it's too late in the day and I'm overseeing a simple workaround, but this could be a cool feature to have imho.

Offline theAVator

  • Full Member
  • ***
  • Posts: 248
  • Acting my shoe size since 1984
Re: idea: masking parts of complex geometry with simple geometry
« Reply #1 on: January 17, 2019, 10:32:03 am »
Just curious, what part of the process crashes KS? Is it the splitting geometry or the positioning?
IDK if it would work any better but if you're able to split the geometry, just save out 3 files: Split one arm off and save it as a new file, split the other and save as a new file, split the other model with no arms and save it as a new file. Then combine the 3 new files. Again, IDK if it would work better, but might be handled better than multiple complex changes in one file.  ??

With the new cut away material in KS8, you could essentially cut off the "bad" arms/hands where you want, and then would have to copy in the replacement arms. With a large complex model though, it would just increase in size.

Offline mattjgerard

  • Hero Member
  • *****
  • Posts: 1448
Re: idea: masking parts of complex geometry with simple geometry
« Reply #2 on: January 17, 2019, 10:53:04 am »
Simple job for the cutaway material applied to your cubes. Hard part would be matching new hands to the cutaway part, unless it was hidden by something or photoshopped afterwards. But certainly workable. The nice thing is that the cutaway material is fast, easy to use and stays active when in performance mode, which is AWESOME.

Offline RRIS

  • Full Member
  • ***
  • Posts: 226
  • Renze Rispens - industrial designer
Re: idea: masking parts of complex geometry with simple geometry
« Reply #3 on: January 18, 2019, 12:39:43 am »
Just curious, what part of the process crashes KS? Is it the splitting geometry or the positioning?
IDK if it would work any better but if you're able to split the geometry, just save out 3 files: Split one arm off and save it as a new file, split the other and save as a new file, split the other model with no arms and save it as a new file. Then combine the 3 new files. Again, IDK if it would work better, but might be handled better than multiple complex changes in one file.  ??

With the new cut away material in KS8, you could essentially cut off the "bad" arms/hands where you want, and then would have to copy in the replacement arms. With a large complex model though, it would just increase in size.

Ah, not sure how the cutaway material works in K8, the company I work for is still on 7 and is likely to skip one or two versions :/ Sound like it's exactly what I needed though.

What you suggest is indeed what I tried to do, to use the geometry editor to split the model into parts. Unfortunately the model was too dense to be able to work with comfortably. In the end I used Blender to split the model and reimport it in Keyshot.