From: tuananhnp
Hello, I'm doing some experiments with the built-in SubD conversion (from OBJ file) in MoI.
With a low-poly OBJ model imported, the SubD conversion creates very smooth surfaces.
However, it tends to convert medium-poly or high-poly OBJ into coarse, somehow faceted, surfaces.
The 1st screenshot shows two OBJ models. The 2nd screenshot shows their corresponding converted SubDs.
It maybe hard to see the difference by looking at the screenshot. But upon close inspection the roughness SubD surfaces are quite apparent.
I have attached the 3dm file below.
Is it a limitation of the built-in SubD conversion? Like it could only smooth simple polygon?
Attachments:
SubD from file - low poly vs medium poly.3dm
Image Attachments:
SNAG-22090403030600.png
SNAG-22090403060800.png
From: tuananhnp
I have tried both Patch Types under "SubD import options" with no luck.
From: tuananhnp
Here is the surface analysis comparison between 2 SubD versions.
Image Attachments:
SNAG-22090403260100.png
From: Michael Gibson
Hi tuananhnp,
re:
> It maybe hard to see the difference by looking at the screenshot. But upon close
> inspection the roughness SubD surfaces are quite apparent.
I think you're probably just seeing a display artifact in the real time viewport display where the display mesher is not making a lot of triangles in a few areas of your heavier model.
That's a normal type of display artifact and doesn't mean your actual model is rough. If you export out to a mesh format you can adjust the export mesh parameters and the "roughness" will be eliminated if you generate enough polygons.
re:
> Is it a limitation of the built-in SubD conversion? Like it could only smooth simple polygon?
No, it is just a mistake in your inspection method where you're closing examining the realtime viewport display mesh which is oriented around speed.
However, it is generally better with sub-d modeling to have as sparse of a control polygon cage as possible for several reasons - it's easier to control fewer cage points and data size will be less. When you have a high density control cage it becomes easier to have things like little bumps in the subd limit surface.
- Michael
Image Attachments:
tuananhnp_subd.jpg
From: tuananhnp
Oh my bad. I checked the way you did and it's indeed sooo smooth!
Thank you Michael for clarifying this. You're the man!