CAD Projection tool


Has anyone tried the new CAD projection tool? I read about it in the release note of V6.0 - a very exciting new feature but I am not sure how to use it, or if it is even available to sim4life light users.


Hi @lj,

the projection tool is available in Sim4Life light. Please refer to section in light manual. I attach here an animation illustrating the projection of a rectangular patch on Yoon-sun arm.


Thanks a lot, @ofli - I will try it out 🙂

I tried this out and it worked perfectly- Thank you! Is there a way to do this using the python interface?

Hi @ofli - Do you know what model parameters are reserved when using the projection tool? I used it to place electrodes on the skin but the area of some of them seems to be a lot larger than it was before the projection.

The projection is based on "Michael Rabinovich, Roi Poranne, Daniele Panozzo, Olga Sorkine-Hornung. Scalable Locally Injective Mappings, 2016"
It tries to preserve angles and lengths (i.e. minimizing two energies). Note in many cases it cannot exactly preserve both though, unless the target is e.g. a cylinder.

While this method works quite well, the implementation depends on the mesh quality and resolution of the target surface. It potentially also can be affected by mesh regions that are relatively far from the pivot (the region where you want to project to). We have some improvements planned in our roadmap to make it work more robustly.

I see- thank you!