Really dumb question about what causes Rhino to slow down


Okay, for those of us who are still coming up to speed with Windows and Rhino, I’ve got a file open that has a lot of 2d version of trees. They’re vector lines, but very busy. (see .jpg attached). The file is not very big, though, – it’s 44 mb. The program is slow, however. I have Windows 7, 64bit, Intel Core i7 quad core processor, Nvidia GeForce 675 m graphics card and 16 gb of ram. I understand how all the trees would slow the program down when I’m moving around the model, but when I am not moving, – say in Layout mode and just typing some text in a corner of a layout page, why is it still slow?

If I turn the layer with the trees off, of course, the program speeds up-- but my question is,why would the program still be slow when I’m not moving the camera around?

Thank you.


If you can upload the file, that will always make it easier to diagnose what is going on. Unless something is odd with the trees, this doesn’t seem like it should be to taxing. Is it possible that they are using some funny linetype that is causing problems? If you try LinetypeDisplay, and set DisplayLinetypes=no, does that help?



Hey Sam, @SamPage

The file, when zipped is 25 mb. The maximum that the Forum seems to allow is 20mb. Do you have Dropbox?

Thank you.


Is that an imported DWG? I’ve had the same issue where a relatively small imported dwg slows the whole thing down. I ended up redrawing the reference curves I needed and hiding the rest.


Yes, sir. Some trees are obj files imported from I then ran either ran projecttocplane on them to flatten them. This is probably the problem.


You could try to pack it per RAR or 7zip. Could be smaller.

(Wim Dekeyser) #7

I suppose you could try to see if there are many duplicate curves in those trees. Also finding short curves and deleting those could help but then make sure that you specify the length of the curves so that what you are left with gives you enough detail.


Thank you, guys. your suggestion worked. I ran selsmall and reduced the number of leaves, then rebuilt the trunks by using the dupedge command, then planar surface.

Thank you, again.