Solid Difference acts like Solid Union

It’s kind of funny that Solid Difference union-ed my geometry. Both are closed breps, and no surfaces coincide. The difference works perfectly in native Rhino though (thru BooleanDifference). Any idea what may not be working?

The image above shows a clipped section of the baked Grasshopper result.

The image above shows BooleanDifference (native) result.

solid difference is hilarious.3dm (32.8 KB)
solid difference is (23.5 KB)



… other than that, perhaps “Rhinoceros 7.7 - Corporate” is hilarious?


My most humble acceptance and apologies for using an underhanded license (I swear I do not yet have the resources, I will one day hopefully)—and for my cadence as well, no excuses.

For the Grasshopper file, I’ll try to remake it with vanilla components and see if it will fare differently. Thank you for replying!

looks like a Normal-Direction problem.
baking and _dir won 't work
see at @magicteddy answer below

(no comments on your behaviour regarding licensing. McNeel is not Adobe or Autodesk.)

When you bake Breps in Rhino, their normals are automatically flipped outwards, so you won’t see the problem.
However this does not happen in Grasshopper where you can have closed Breps with normals pointing inside.

You need to craft a C# component with Brep.Flip() method


thanks for pointing out / remind my to this topic - changed my post above.