Can Grasshopper for Rhino 6 works on SubD and Extrusion?

Hi, one simple question,

Grasshopper for Rhino 5 couldn’t work Extrusion type.
We have to explode Extrusion, when we want to work on extrusion.

Will Grasshopper Rhino 6 can read and bake those types as original?


Hi Yong Sung Kwon - what do you want to be able to do with an extrusion that you cannot now?


Dear Pascal,

sometimes we have a huge model and a large part of such a model can be made with extrusion.

When I can keep those parts as extrusion, Rhino speed will be increased noticable and the size of data will be decreased a lot.

The good example is a model that I worked fot Qatar National Museum. I used there a lot of simply boxes for details. The Dimension of thoses boxes are all different, therefore I have to use Grasshopper. But with Grasshopper I could not create Extrusion Type.

If it was possible, I could have few hundred megabyte 3dm, instead of gigabyte. and I would not have to set Mesh jagged/No Anti alias.


Hi Yong Sung Kwon - Yep… I understand why you use extrusions in Rhino, but I would like to know what you want to do with them in GH that you cannot now?


well… for example,

  1. in GH simply extruded geometry to bake as extrusion type

  2. read extrusion in Rhino as extrusion to GH and scale, move, rotate, orient, etc… and bake it as extrusion

Ah, OK, sorry, I understand - thanks - so, the goal is to output extrusions, not use existing ones. I do not know but I think this can be scripted, I think I have something lying around that may be a good basis for spitting out extrusions via a Python component.

@DavidRutten - is there currently a way, or a plan, to make the output from GH extrusion components make extrusion objects?


No. It’s on the long term pile of geometry types to support, but GH1 does not and probably will not support Extrusions. If extrusions are imported they will be converted to breps, and everything inside GH is only ever a brep. I assume GH2 will have more direct support for these types, as well as sub-ds.

RH-42662 is fixed in the latest WIP