How use Ev1Der

Hello all,
I try to determine curvature of the surface. How use Ev1Der or Ev2Der I can do it?

Hi @vadvirus

to use Ev1Der you have to apply the correct u and v parameters and you get the according tangent vector in u and v direction. Same with Ev2Der you get the second derivative.

What’s exactly your problem?

Here is an SDK sample that might help you.

https://github.com/mcneel/rhino-developer-samples/blob/6/cpp/SampleCommands/cmdSampleSurfaceCurvature.cpp

You can find more SDK samples in our developer samples repo on GitHub.

– Dale