Optimization of exported objects

Hi to all,
My question is, is there way to optimize or lower surface count of objects exported from another program. I need to use some step objects from catia and they slow the speed of rhino. They also have some inner surfaces i dont need. But that is another case i quess.
Thanks for time and suggestions already.

No, you cannot automatically optimize NURBS objects that are imported from a STEP file.
This means you will have to find ways to deal with the object the way they are.
You haven’t said what it is you will do with these so I can only give a few general tips.

I’m guessing it’s not just one object that comes in but possibly a few hundreds? Do you need all of them? Get rid of the smaller ones by using SelSmall.

Take a look at your mesh settings for the document - if already set at Jagged & faster you could try to make a custom setting that produces even less faces.

Only have one object visible at a time while working on that one.

Extract the render meshes of the objects you are only using as visualization and join the ones you can (they don’t need to touch one another for this). Then delete the NURBS version.

Use DeleteHole to get rid of holes for fasteners if you don’t need them.

Hi Sirin- are you looking to extract complete parts that are not needed, or invisible or unneeded surfaces from a joined shell/polysurface? Or both?


I use objects mostly as references. I make designs related & on to them,
so they are not my main onjects and I do not make them visible all together at the same time in order to speed up.
But i didn`t know the “Selsmall” or “Deletehole” commands.

I thougt there might be a trick like in 3ds max “optimizer modifier” or “display as a box” option. I ll try suggested methods.
Thanks again.

Mostly second option.
I explode blocks, then i extract and delete unwanted parts.
But whan its comes to invisible surfaces there is lots of boring-time consuming work.
I figured i might demand objects from catia as shells only, not any interior surfaces. Maybe that could also work.

Not sure if you are aware of the option available in display modes to only show the bounding box of an object when navigating the scene - actually you can also set it to always display them as their bounding boxes. I don’t personally use that option so I cannot say anything about its usefulness. You could make a new display mode and assign that to a few objects only if you wanted to…

Worksession may be useful for you. Import the objects into a separate Rhino file. Open/create the Rhino file you will be working in. Then Worksession command and Attach the file with the objects. The objects will be visible and can be used as background without cluttering the file you are working in. You can have multiple attached files and turn them on and off as desired.