orient issue

Hi everybody.

I'm stuck in front of the orient component.

I would like to control orientation of an array of breps that would be hooked to grid points.

I've already created the grid, the atractor point, and the vectors defining normal planes:

here is a picture of the definition and the scene

first issue , is that planes x and y directions are sometimes upside down (see above) depending on the attractor position..

second problem is that I need to find the base plane of my brep for the orient component? but how to get it?

thanks for your help.

Replies to This Discussion

Permalink Reply by David Rutten on December 1, 2010 at 10:11am

Hi tib,

creating a plane from origin + normal is indeed a problematic approach if you care at all about plane orientation. There's simple an infinite number of possible planes that satisfy any given origin point + normal direction and Grasshopper has to pick one. It's not possible to do this in a continuous fashion (see: hairy ball theorem) so you'll always get a flip somewhere.

You can either choose to construct your planes differently or to post-process them to achieve the orientation you want.

See attached for a possible solution.

--
David Rutten
david@mcneel.com
Seattle, WA

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