best methods for finding angles between faces

I am curious if there are any new methods for finding angles between faces of a brep. Currently I am using sandbox to find adjacent faces and creating vectors from the shared curve to each face center point to determine the angle. This method takes a bit of data juggling and I think there must be a simpler way... Any ideas??? THANKS!!

Replies to This Discussion

Permalink Reply by ng5 Alex on September 9, 2015 at 7:37am

wrong post answer, sorry thought you were wondering about meshes!

best

alex

Permalink Reply by Daniel González Abalde on September 9, 2015 at 8:21am

You can measure the angle betwen normals and add 180 degrees.

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Permalink Reply by Ethan on September 9, 2015 at 10:47pm

thanks guys both answers very helpful!

Permalink Reply by peter fotiadis on September 10, 2015 at 1:12am

Anyway that's rather easy to do with ... er ... you know what I mean I do hope, he he.

Notify if you want the Dark thingy.

best, Peter

Permalink Reply by taz on September 11, 2015 at 11:14am

Old school (math)...

http://www.grasshopper3d.com/forum/topics/q-specific-pairings-from?...

Permalink Reply by Riccardo Majewski on September 14, 2015 at 6:09am

XD sorry for late reply.

Take a look at this.

Some surface can have a complex shape thus the central point of the face can be misleading to the solution.

Every surfaces have perimeter/edges going counterclockwise (if you look the surface from the top, normal positive), this is useful and necessary here.

Given a location on an edge, find local (closest point) surface normal and local edge direction (tangent/vector). By doing vector cross product between those two vectors you can achieve a vector always pointing inside of the surface.

Then you can correctly find the inside/outside angle of every brep edge.

My solution take samples everywhere (in the edges) in a brep.