topic Re: Retopology modifier "IPOPT max iterations exceeded" error message in 3ds Max Modeling Forum

Retopology modifier "IPOPT max iterations exceeded" error message

mantasdm — Thu, 03 Feb 2022 09:40:49 GMT

Struggling with auto retopo here (retopo modifier). So there's this screw thread object/file from CAD, which looks pretty clean (as far as "clean" goes for CAD files lol), but I just can't get it to work with Auto Edge function (which IMO is necessary to get good/clean results/edge loops. I always seem to get this "IPOPT max iterations exceeded" error. Tried a bunch of different settings but with no success, it only works with Auto Edge turned off, though results are pretty bad then. Here's fbx file of the object if anyone's fancy about taking this little challenge: Screw Thread Cad Model

Re: Retopology modifier "IPOPT max iterations exceeded" error message

miledrizk — Sun, 06 Feb 2022 11:18:27 GMT

Hi,

I imported your file and added the Retopo modifier,

I kept the default settings, just increased the polygons count to 70000,

Here you can download the Max file containing the mesh with the modifier on top:

https://drive.google.com/open?id=1-1Lb3ORb06NUD7ExYKm2ZN-oCeZjqnGt&authuser=miledrizk%40gmail.com&usp=drive_fs

Re: Retopology modifier "IPOPT max iterations exceeded" error message

mantasdm — Tue, 08 Feb 2022 11:48:32 GMT

Hey there, your file requires access

Re: Retopology modifier "IPOPT max iterations exceeded" error message

miledrizk — Tue, 08 Feb 2022 12:57:39 GMT

Sorry for that,

Can you try now

Re: Retopology modifier "IPOPT max iterations exceeded" error message

mantasdm — Thu, 10 Feb 2022 14:47:25 GMT

Thank you for your effort, Miledrizk, but it still doesn't achieve what I'm looking for. In your example file Retopo modifier still didn't take into account any of the hard edges (if it did, edge loops would follow along those hard edges nicely). And so that's exactly the result I'm getting currently , which is not good. BTW, you've set Auto Edge to Smoothing Groups, and just so you know, mesh from CAD doesn't have any smoothing groups by default, it only has explicit normals, which makes it look like it has. So setting Auto Edge to Smoothing groups without manually creating smoothing groups does nothing. And if you DO create these smoothing groups and/or set it to By Angle it always crashes, which is the main issue here.
So in short the issue still remains- can't have clean topology results with auto retopo because the only way for retopo to work is don't use any of the Auto Edge features, which is why the topology comes out bad.

Re: Retopology modifier "IPOPT max iterations exceeded" error message

miledrizk — Thu, 10 Feb 2022 16:26:54 GMT

Hi,

In your original post, what I understood was that Max was throwing an error

When using the Auto Edge feature and all I did was add the Retopology modifier and see

If everything works fine. I didn't know what kind of a result you were looking for.

For the Smoothing Group thing, the reason why you have no SG is that you left the Smoothing Groups

Unchecked when importing the FBX file. If you check it you'll see that you will have 3 different smoothing groups

On your model.

Now back to the issue, I suggest you do some welding for the vertices with a very low value,

Add a Quadify Mesh modifier, try different values with the Quad Size, I think something close to the 1 or 2 is good,

Now, add the Retopology modifier, uncheck Smoothing Groups and experiment with different Face Count.

Re: Retopology modifier "IPOPT max iterations exceeded" error message

mantasdm — Thu, 10 Feb 2022 19:05:26 GMT

Oh yeah, didn't notice Smoothing Groups on import was unchecked. Although I see these default SG's straight from CAD had some issues (a few random polys with the wrong SG). So I think it's better to fix/create them inside Max anyways, which is easily done with Smooth modifier set to auto.
Tried using Mesh Cleaner modifier as well, it found 1 Degenerate Edge, so I thought that might be the problem, I then re-exported the mesh from MoI with adjusted settings and now Mesh Cleaner finds zero problems with the mesh. I also tried exporting it wits quad/tris and ngons. Same problem in every case. Tried welding and Quadify Mesh, nothing is helping.
The mesh now is as clean as it gets, and the hard edges are really clear (I mean Max should have no problem of understanding where it should put the edge loops/hard edges), plus the smoothing groups are now correct straight from CAD.
Does this mean this shape is just too complex for Max retopo to handle? which doesn't look like a complex shape at all.
BTW, here's new/updated FBX file (which shows 0 problems in Mesh Cleaner): https://www.dropbox.com/s/cxmgylnx65qgev8/Thread_Retopo_Test_NEW_v1.fbx?dl=0

Re: Retopology modifier "IPOPT max iterations exceeded" error message

engr.haider.pk — Mon, 05 Dec 2022 01:44:33 GMT

Thank you for the help.

can you please write the optimum settings for retopology in 3D Max?