Mesh to Solid conversion mathematical approach

[Anonymous]

Hi,

Hope you can help me. I have some questions

1-What is the mathematical approach Fusion 360 use to convert Mesh to Solid? And Meshmixer?

For example: approx model least-squares, B-splines, gradient descent or any other?

2-And what is the surface fitting strategy? Is it a functional thin-energy plate?

For example in Rhino they first turn the triangular mesh into quadrangular and then they apply Catmull-Cark subdivision.

3-Why there is a 10.000 facet threshold for this conversion?

4-I know you can customise the tolerance but is there a minimum error in this conversion or it dedend on the model?

Cheers,

Aida

[jean.flower]

Hi Aida and thanks for your questions.

I won't cover everything, but here's a start. 

There's a Mesh to BRep conversion tool in Fusion which is precise.  It creates a body with planar facetted geometry.  There's no B-Spline geometry or surface fitting involved.  The reason for the face count limit is that the bodies that result from this type of mesh conversion can cause performance and robustness problems for larger meshes. There's a previous discussion here that may be interesting to you

https://forums.autodesk.com/t5/fusion-360-design-validate/what-s-the-quot-new-quot-mesh-gt-brep-poly...

There are tools for creating sketch geometry from meshes and this can be a powerful approach

https://www.youtube.com/watch?v=6AtFuv4TQDw&ab_channel=AutodeskFusion360 

Another tool that can be useful is to build a T-Spline that's nearby and then pull its shape onto the mesh

https://www.pinterest.co.uk/pin/805229608362683189/ 

Do you have a particular mesh you're trying to work with?  I'd be interested to learn more about the context and what you need to achieve.
Jean