Srf Selection via Normal Directions

Hi, is there a way to select planar surfaces based on their normal directions? Thanks

Scriptwise, yes… Are you looking for something very strict - like exactly this normal angle and nothing else - or something more general like something that vaguely faces the camera or a certain direction?

Something more general please.

Well, since you didn’t list any criteria, below is just an example of a script I adapted from my library. All surfaces whose normals face more towards the camera than away from the camera will be selected. (1.2 KB)

This can be easily adapted to select surfaces whose normals face in one particular direction (like world Z) within a given angle tolerance…

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Hi Mitch,
For some reason I get this error message when I try to run this script…
Any idea on how to fix this? (zero programming experience…)

I’m trying to replicate the problem, but mine works fine.
Have you tried re-downloading the script?

If you run cmd ‘editpythonscript’, then open the script, does line 26 state:
and line 39

Hello - are you in V5 or V6?


@Jaxx What version of Rhino are you using? Early versions of V5 for Windows and Mac did not support the state argument. You could try the one below, I guess. Or update your Rhino. (1.3 KB)