Principal curvature lines on surfaces: need some advice please

by Niels De Temmerman

Feb 9, 2011

Hi,

 

To generate a grid structure based on a surface, I wanted to determine the principal curvature lines in a UV-point. This seems more complex than it sounds. Though, there is a Principal curvature component in GH, and it outputs the two values for the principal curvature in that point, and the two orthogonal directions. But how to construct a curve based on that data?

 

Anyone willing to share some experience?

 

I've included a snapshot of the (simple) definition generating a hypar, and a UV-point on that surface.

Also you can find the ghx attached

 

Thanks!

 

Niels

 

more info:

http://en.wikipedia.org/wiki/Principal_curvature

  • up

    David Rutten

    Hi Niels,

     

    a principal curvature line contains a very large (in a purely mathematical sense, infinite) number of points. The Principal Curvature component only gives you information for a single point. If you want to take the principal direction at that location and 'grow' a complete principal curve, you'll need some form of iteration, which means you'll need to write a VB/C# script.

     

    I wrote something that tracks curvature lines along the strongest kappa in a single direction until it hits the surface edge.

     

    --

    David Rutten

    david@mcneel.com

    Poprad, Slovakia

    11

    Feb 9, 2011

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    • up

      Chris Tietjen

      There's some redundancy of components that could be eliminated.

      Chris

      4

      Feb 9, 2011

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