Double skin solid

I already know answer is NO , but any suggestion or future implementation in rhino would help
Could we have a closed brep that is defined between two closed brep rather than a close brep inside another one . I think the struggle is with the itersection and connectivity of the faces .

Hello - NonmanifoldMerge will make a single brep from these but you will not, I think, be able to get the inside face normals to point inward.


If the plan is to 3D print this object, there must be a [small] portal from inner surface to the outer surface.

For 3D printing, this probably does’t matter, as you end up slicing a mesh model of the object to produce closed polylines for the printer toolpath to fill, I only think that closed-ness and nesting matter in this case. But if you Mesh the object first, I think you could flip the inside mesh separately if you really needed…

Well in my case there is no need of surface’s normals and the operation is for point inclusion (it works fine) and not 3D printing

I am seeking the same method for merging meshes (e.g. two mesh boxes ) if possible ?

Well, if you’re only looking for point inclusion, you do not need either a disjoint solid or mesh - just get the points contained by the outer shell and exclude points contained by the inner shell… The applicable RhinoCommon methods are Brep.IsPointInside() and Mesh.IsPointInside()…


Rhino cannot make a model of a ping-pong ball because Rhino is a surface program rather than a solid program. This is serious flaw because many real world objects (e.g., closed containers) have topology similar to the ping-pong ball.