Revolve Surface creates first degree surface from polylines

Hello Everyone,

I have a problem (or not) with revolve surface and couple of other commands, I can’t remember when this started -my current rhino version is Version 5 SR7 64-bit (5.7.31213.18395, 12/13/2013).

What happens is -as shown by the attached images, when I use a polyline with the revolve command, the usual output is a polysurface but for some reason the output is now a surface -as shown in the “what” details window, which I can open its control points and edit normally, also something of note is that the surface is a first degree surface in one of its direction which did not use to happen.

This occurred as well with Blend Surface command.

Is this a bug or a new feature, I can’t seem to find any other topics about this?

Same Rhino release here. Polyline revolved to polysurface, just as you would expect. So maybe you got some options changed?

Could you post a file?

Sure, here is a file with couple of examples, one created with revolve and the other with blend surface and as shown in the properties pane they are both being read as a surface!

polysurface issue.3dm (431.7 KB)

This sounds like crease splitting got set to No. This seems to happen occasionally, nobody knows why exactly.

When crease splitting is set to No, making surfaces from kinked curves creates kinked surfaces. When crease splitting is set to Yes, (default) it creates polysurfaces.

To check/change this, type CreaseSplitting and if necessary change SplitAlongCreases to Yes.

Let us know if this helps…



Great, that solved it!!
Huge thanks Mitch

Hi Osama- are you using any non-default plug-ins?