Hello everyone, I have created several polysurfaces in Rhino, but as you can see, the normals of all surfaces are pointing in two directions, which is not the desired outcome.
I’m wondering how I can unify their directions towards one direction using Grasshopper?I had tried flip plane component to achieve my result,the guard input choose a list item,but it falied.
Any useful response will be greatful for me.Thx very much
Your surfaces join to a closed polysurface. Joining makes all normals face outwards. You can then explode the closed polysurface again and the surface normals should all point outwards.
Since this object is built of triangles only, I’m wondering why you aren’t using meshes…
nut.gh (244.0 KB)
Thanks a lot . 
It’s just I am more accustomed to working with polysurfaces.
Your GH file has only the internalized surfaces, not the code that created them, so it’s impossible to know how they were made. In general though, surfaces have flipped normals when the direction of their edge curves is reversed. It might be possible to modify your code so they all have the same direction.
Originally, I modeled it in 3ds Max, but encountered the issue of non-coplanar surfaces.So in order to resolve this problem I made the decision to rebuild the model in Rhino that each step has become invisible during this process.
It was solved after I followed advice from Martin.
Thx for you attention.
