I got this file from a customer. I don’t know why, but some operations on this file are really taxing my computer? The polygon count isnt that high. Does anyone have an explanation?
Hi @simon9
What operations are causing problems? And what are your computer specs? The file is obviously a polymesh that has been converted to NURBS, and the is rarely the best way to go - it results in faceted geometry consisting of many, many individual surfaces (in this case 27.000+ of them). The better way would be to convert the original mesh to NURBS, either by reverse engineering manually or using tools like QuadRemesh or one of the specialized plugins. Operations like booleans or fillets on a NURBS polysurface this complex is bound to be taxing - even on powerfull workstations, I think.
HTH, Jakob
Hi Normand,
It also thought this seemed like a very odd shape to be a solid polysurface. You are saying it is a Mesh file converted to NURBS? I have no idea why my customer did this.
I don’t see a real need to even try to convert it to NURBS, no matter the method. I can work with Mesh files as well. Especially if the conversion bogs down my computer so much 
I’ll ask the client if he can send me the original mesh.
This is also preventing me from doing a SubDivide on the mesh to smooth the model out.
Some background: We are a styrofoam milling company. I edit these models to prepare them for the CNC program. This file is lagging my computer on all basic operations: Copy/pasting, moving, exporting, saving…
Hoi Simon -
There is no lagging here on Rhino 6 with these basic operations. That might indicate an issue that is system-specific (though I get a “missing picture” warning when opening that here - if that picture is huge, that might have something to say…). Can you post the result of the Rhino SystemInfo command?
There is quite some lagging when doing a Boolean operation on this object but what’s taking time is generating a new display mesh. I agree with you that you might as well use a mesh workflow here.
-wim
Hi Wim,
I also get the missing image warning. So we can exclude that. I didnt reallise that I have hidden half the model in the uploaded file. When everything is showing, it slows the PC down more, obviously. Also we duplicated the shells, to make them thicker, this probably isn’t helping the preformance and isn’t the best way to do things, but the CNC doesn’t care about that 
My main question was why this seemingly undetailed model is such a slug, I guess it is answerred by Normand already.
Below you can see the output of the SystemInfo command, let me know if there is something I could upgrade in my desktop, I am curious !
Rhino 6 SR34 2021-2-3 (Rhino 6, 6.34.21034.07001, Git hash:master @ 2fec8130f097ca52a8bc9f334c3ed4a5921c5e30) License type: Commercial, build 2021-02-03 License details: Cloud Zoo. In use by: Simon () Windows 10.0.0 SR0.0 or greater (Physical RAM: 32Gb) Machine name: PNP-WS2 Computer platform: DESKTOP Standard graphics configuration. Primary display and OpenGL: NVIDIA Quadro K2200 (NVidia) Memory: 4GB, Driver date: 8-27-2019 (M-D-Y). OpenGL Ver: 4.6.0 NVIDIA 431.86 > Accelerated graphics device with 4 adapter port(s) - Windows Main Display attached to adapter port #0 - Secondary monitor attached to adapter port #1 OpenGL Settings Safe mode: Off Use accelerated hardware modes: On Redraw scene when viewports are exposed: On Anti-alias mode: None Mip Map Filtering: Linear Anisotropic Filtering Mode: High Vendor Name: NVIDIA Corporation Render version: 4.6 Shading Language: 4.60 NVIDIA Driver Date: 8-27-2019 Driver Version: 26.21.14.3186 Maximum Texture size: 16384 x 16384 Z-Buffer depth: 24 bits Maximum Viewport size: 16384 x 16384 Total Video Memory: 4 GB Rhino plugins C:\Program Files\Rhino 6\Plug-ins\Commands.rhp "Commands" 6.34.21034.7001 C:\Program Files\Rhino 6\Plug-ins\WebBrowser.rhp "WebBrowser" C:\Program Files\Rhino 6\Plug-ins\rdk.rhp "Renderer Development Kit" C:\Program Files\Rhino 6\Plug-ins\export_ACAD.rhp "AutoCAD file export : export_ACAD" C:\Program Files\Rhino 6\Plug-ins\RhinoRender.rhp "Rhino Render" C:\Program Files\Rhino 6\Plug-ins\rdk_etoui.rhp "RDK_EtoUI" 6.34.21034.7001 C:\Program Files\Rhino 6\Plug-ins\rdk_ui.rhp "Renderer Development Kit UI" C:\Program Files\Rhino 6\Plug-ins\NamedSnapshots.rhp "Snapshots" C:\Program Files\Rhino 6\Plug-ins\IronPython\RhinoDLR_Python.rhp "IronPython" 6.34.21034.7001 C:\Program Files\Rhino 6\Plug-ins\RhinoCycles.rhp "RhinoCycles" 6.34.21034.7001 C:\Program Files\Rhino 6\Plug-ins\Toolbars\Toolbars.rhp "Toolbars" 6.34.21034.7001 C:\Program Files\Rhino 6\Plug-ins\3dxrhino.rhp "3Dconnexion 3D Mouse" C:\Program Files\Rhino 6\Plug-ins\Displacement.rhp "Displacement"
Your video drivers and it looks like Windows are both out of date. But that’s not going to make a 5-figure surface count snappy. A modern video card can certainly help with the viewport display on large models.
Wait Windows is out of date? It does updates every other day it feels like… I’ll need to look into that.
Maybe we’ll look into upgrading our GPU, what would be a good recommendation? Although I heard it’s not really the best timing to upgrade, isn’t there a big scarcity going on with all the bitcoin miners and probably also because of COVID ?
Maybe Windows isn’t out of date, but the entry looks a bit different from mine…
Yes it’s almost impossible to actually get a useful video card without paying scalper’s prices, unless you buy a complete PC(at inflated-assembled-PC prices) from an OEM. Mining is actually a relatively minor part of the problem, compared to a TWENTY PERCENT increase in demand for computers due to everyone being at home. I have an old 1080ti (I used to have four of them but don’t do much rendering so I took advantage of the insane prices to upgrade the rest of my system!) and it’s “enough” to see the performance improvement on large models.
I see, makes sense, I thought it was supply difficulties in the factories due to corona.
Also aren’t big 3D models more CPU intensive rather than GPU ?
It was, but those have been mostly sorted, it’s that there is just no available capacity.
They are demanding on everything.