Surprisingly Large Number of Rendering Materials?

Continuing the discussion from Rhino blocks it just me? Help me understand:

I’m working on a file (originally with blocks, imported from Solidworks) that shows a large number of rendering materials using Audit (2,993). However, the Material Editor only shows 27 materials in use (about half of which use texture map files of photos). Curiously, Purge does not delete any of the 2,993 materials shown.

Does every color used in a texture map create a new material (which is not explicitly shown in the Material Editor), or is there something else going on?


Hmmm… I see that nobody wants to take a stab at this!

@dan: Any insights? In particular:

  1. Does every color in a texture create a (hidden) color, or is something else going on?
  2. Would this phenomenon create a larger file size or any other undesired behavior or performance issue?



The Audit command is exposing an implementation detail of the Rhino 3DM file. Every object that has a material assigned to it also has a corresponding material object that describes the material. If you assign one material to 100 objects, 100 rendering material objects, all identical in their parameters, are added to the model. The Rhino for Mac material editor determines how many unique materials are in the model and only displays a thumbnail for each unique material.

Many thanks for the explanation, Martin! This now makes complete sense.

(The culprit on my end turns out to be a large number of 3D fasteners that came in as blocks and needed to be exploded.)

After some testing, it’s also interesting (and good) to see that when using Blocks, each instance does not add to the total number of rendering material objects.

I know there has been prior discussion about improved Solidworks importing into Rhino—very useful where numerous components and blocks are involved. Any updates on this front for either WinRhino or MacRhino?


@tim Can you provide any insight here?

Hi Dave- what improvements are you thinking of here? Any details?



There is a good discussion of the issue here: Import Solidworks 2015 files and several other threads if you search for “Solidworks”.

In sum, current versions of SW do not import into current Rhino5 and development efforts from Solidworks for this ability have been (are?) stalled or unknown?

In the meantime, I’m importing STEP files from my Solidworks-using engineer with good success regarding model integrity. However, this is far from ideal since:
A) everything comes in as one layer and
B) all blocks need to be exploded in order for me to edit anything.

This process is very time-consuming for iterative design changes (and files sizes increase by a factor of at least 5).

Ultimately, ideal behavior in Rhino would provide layers and block behavior for SW files. In a perfect world (to dream, right?!?) various assembly components from SW would be a 1st level layer, with the individual geometry for these components being sublayers. This would permit much MUCH simpler viewing of desired components and editing.

Thanks for looking into this and good luck!


The Solidworks import is a plug-in from a 3rd party (Datakit), and as such it is licensed from them by McNeel for use in Rhino in exchange for… money. So I guess that making Rhino V5 SW2015 compatible would be relatively expensive - how expensive actually, I have no idea, but an individual license of their product is around $1000 IIRC


Thanks for the info, Mitch. If this is affordable, it seems like a worthwhile consideration given the number of designers collaborating in this fashion. If not, guess I’ll have to bone up on my Solidworks skills! (Ugh…)