Questions about STL files for simulation

[zhulidong12138]

Hello, I'm new to Julia and WaterLily. WaterLily is very good and perform excellent simulation!
I would like to use WaterLily to simulate some underwater bionic robots, but defining the model through SDF is too complicated. Is it possible to use 3D STL files exported from SolidWorks for the simulation? Or is there an easy way to transform complicated 3D STL files to signed distance function?
Thank you!

[weymouth]

"Too complicated"?! What's complicated about them!?!? https://youtu.be/8--5LwHRhjk?si=GGiQ8j3N0U3dUdtJ

I'm just kidding. We've got two options currently:

1. First, there is https://github.com/WaterLily-jl/ParametricBodies.jl, which allows you to import any parametrically defined curve as a geometry. It's limited to curves, but they can live in a 3D space either as a space curve, a planar membrane, or a body of revolution.
2. Second, there is a link with https://gismo.github.io/ which is a fully 3D NURBS modelling framework. @marinlauber should have some examples from his own work linking WaterLily to G+Smo available soon.

Neither of these are a typical STL reader. You could write a simple for loop yourself to check the SDF from each of a million triangles in an STL - but that simulation would be very slow. Instead, this is the sort of thing which should be handled by a meshing package like https://github.com/JuliaGeometry/Meshing.jl or https://github.com/juliageometry/descartes.jl or maybe something else @sjkelly has developed.

I decided to focus on the parametric geometries myself, but I'm super interested to see someone add fast STL measuring to WaterLily.