Why MOI 3D curves and geometry look more clean as compared to Rhino V6? IN this case, the smoothness of curve and sharpness of corners. Same with grid display.
I see them about the same, if anything Rhino is sharper/cleaner (with a 4K display, so that might be cheating a bit).
Go to Tool>Options>View>OpenGL, and set your Antialiasing up to max available:
Yeah I already turned up antialiasing setting, I thought this might be an issue. Also tried to see if there is certain setting to turn up just curve and edge fineness. Yeah! 4k display is clearly tricking here.
I have a decent system here.
Windows 10.0 SR0.0 or greater
(Physical RAM: 32Gb)
AMD FX 9590 4.7 GHz
AMD Radeon ™ R9 390 Series (OpenGL ver:4.5.13506 Compatibility Profile Context 23.20.15015.1002)
What does Rhino command _SystemInfo tell you it is using as display adapter? (just paste the contents of the command here).
Rhino 6 SR1 2018-1-19 (Rhino 6, 6.1.18019.22501, Git hash:master @ 0bcd263b0c48187476e0b69ada5ee6333b9cda45)
Windows 10.0 SR0.0 or greater (Physical RAM: 32Gb)
AMD Radeon ™ R9 390 Series (OpenGL ver:4.5.13506 Compatibility Profile Context 23.20.15015.1002)
OpenGL Settings
Safe mode: Off
Use accelerated hardware modes: On
Redraw scene when viewports are exposed: On
Anti-alias mode: 8x
Mip Map Filtering: Linear
Anisotropic Filtering Mode: Height
Vendor Name: ATI Technologies Inc.
Render version: 4.5
Shading Language: 4.50
Driver Date: NA
Driver Version: NA
Maximum Texture size: 16384 x 16384
Z-Buffer depth: 24 bits
Maximum Viewport size: 16384 x 16384
Total Video Memory: 8 GB
C:\Program Files\Rhino 6\Plug-ins\Commands.rhp “Commands”
C:\Program Files\Rhino 6\Plug-ins\rdk.rhp “Renderer Development Kit”
C:\Program Files\Rhino 6\Plug-ins\RhinoRender.rhp “Rhino Render”
C:\Program Files\Rhino 6\Plug-ins\rdk_etoui.rhp “RDK_EtoUI”
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\RhinoCycles.rhp “RhinoCycles”
C:\Program Files\Rhino 6\Plug-ins\Toolbars\Toolbars.rhp “Toolbars”
C:\Program Files\Rhino 6\Plug-ins\3dxrhino.rhp “3Dconnexion 3D Mouse”
C:\Program Files\Rhino 6\Plug-ins\Displacement.rhp “Displacement”
For this bit I have logged a new YT item: RH-43733
Looks good indeed, you are on adrenalin 
Yeah Indeed. It appears so. 
That’s why I could’t find possible reason for woolen thread like look of curves.
I have no further ideas at the moment, @stevebaer or @jeff probably have better ideas.
Thanks Nathan. I thought I might point out this on Serengeti. While using different interface from different CAD programs, I felt it naturally itchy to see jagged curve/edge display and I think that it can make a difference on interface. I’m hopeful that you guys will improve it before I buy 4k display.
Maybe you don’t like the thickness? I can’t really tell. Try running the TestWireThicknessScale command in Rhino (this is a test command so you need to type the entire thing in). Enable this feature and play with the Scale factors.
Hi Steve! In options/display modes/shaded/Object/Curves, I changed curve width to 2 pixels. so, it’s little thick than default value. While comparing to MOI, I saw that MOI looks like adding anti-aliasing layer on top of viewport and curves look like in some graphic design application, for example adobe illustrator. It’s a subtle but enough difference to make the display look like mac in windows, even on low configuration machine. Meanwhile, I will play with TestWireThicknessScale. Thanks for your attention.