Input Geometry - Creating Unexpected Results

Hello,

I’ve noticed something odd when using surface edges of existing geometry to make new surfaces.

Although the existing is a single span surface (green), pulling an extrusion or duplicating (pink) its edges results in messy multi-span surfaces.

Is this a glitch?

Thanks,

check.3dm (207.8 KB)

Rhino 7 SR7 2021-5-18 (Rhino 7, 7.7.21138.11001, Git hash:master @ 175cf0b9405e059f3075a5720c0c37a9d52b6a5c)
License type: Commercial, build 2021-05-18
License details: Cloud Zoo

Windows 10.0.19041 SR0.0 or greater (Physical RAM: 16Gb)

Computer platform: LAPTOP - Plugged in [100% battery remaining]

Hybrid graphics configuration.
Primary display: Intel(R) HD Graphics 4600 (Intel) Memory: 1GB, Driver date: 8-16-2018 (M-D-Y).
> Integrated graphics device with 3 adapter port(s)
- Windows Main Display is laptop’s integrated screen or built-in port
Primary OpenGL: NVIDIA Quadro K1100M (NVidia) Memory: 2GB, Driver date: 4-23-2019 (M-D-Y). OpenGL Ver: 4.6.0 NVIDIA 425.45
> Integrated accelerated graphics device (shares primary device ports)
- Video pass-through to primary display device

OpenGL Settings
Safe mode: Off
Use accelerated hardware modes: On
Redraw scene when viewports are exposed: On
Graphics level being used: OpenGL 4.6 (primary GPU’s maximum)

Anti-alias mode: 4x
Mip Map Filtering: Linear
Anisotropic Filtering Mode: High

Vendor Name: NVIDIA Corporation
Render version: 4.6
Shading Language: 4.60 NVIDIA
Driver Date: 4-23-2019
Driver Version: 25.21.14.2545
Maximum Texture size: 16384 x 16384
Z-Buffer depth: 24 bits
Maximum Viewport size: 16384 x 16384
Total Video Memory: 2 GB

Rhino plugins that do not ship with Rhino
C:\Program Files\Common Files\McNeel\Rhinoceros\7.0\Plug-ins\KeyShot7RhinoPlugin (486807a0-d332-4669-8086-e0497d91acd5)\1.7.0.0\KeyShot7RhinoPlugin\Rhino 5.0\KeyShot7RhinoPlugin.rhp “KeyShot7RhinoPlugin” 1.7.0.0

Rhino plugins that ship with Rhino
C:\Program Files\Rhino WIP\Plug-ins\Commands.rhp “Commands” 7.7.21138.11001
C:\Program Files\Rhino WIP\Plug-ins\WebBrowser.rhp “WebBrowser”
C:\Program Files\Rhino WIP\Plug-ins\rdk.rhp “Renderer Development Kit”
C:\Program Files\Rhino WIP\Plug-ins\RhinoScript.rhp “RhinoScript”
C:\Program Files\Rhino WIP\Plug-ins\RPC.rhp “RPC”
C:\Program Files\Rhino WIP\Plug-ins\IdleProcessor.rhp “IdleProcessor”
C:\Program Files\Rhino WIP\Plug-ins\RhinoRenderCycles.rhp “Rhino Render” 7.7.21138.11001
C:\Program Files\Rhino WIP\Plug-ins\RhinoRender.rhp “Legacy Rhino Render”
C:\Program Files\Rhino WIP\Plug-ins\rdk_etoui.rhp “RDK_EtoUI” 7.7.21138.11001
C:\Program Files\Rhino WIP\Plug-ins\rdk_ui.rhp “Renderer Development Kit UI”
C:\Program Files\Rhino WIP\Plug-ins\NamedSnapshots.rhp “Snapshots”
C:\Program Files\Rhino WIP\Plug-ins\Alerter.rhp “Alerter”
C:\Program Files\Rhino WIP\Plug-ins\RhinoCycles.rhp “RhinoCycles” 7.7.21138.11001
C:\Program Files\Rhino WIP\Plug-ins\Toolbars\Toolbars.rhp “Toolbars” 7.7.21138.11001
C:\Program Files\Rhino WIP\Plug-ins\3dxrhino.rhp “3Dconnexion 3D Mouse”
C:\Program Files\Rhino WIP\Plug-ins\Displacement.rhp “Displacement”
C:\Program Files\Rhino WIP\Plug-ins\Calc.rhp “Calc”
C:\Users\sach\AppData\Roaming\McNeel\Rhinoceros\packages\7.0\PanelingTools\2018.12.17+906\PanelingTools.rhp “PanelingTools”

I tried in Rhino 6 and it’s the same…

Hi Sach - in this case, just untrim the green surface - the edge has been split or something and is more complex than the natural surface edge. RefitTrim also helps in cases where the trim is ‘substantial’ and not trivial.

-Pascal

That’s a good point. On this occasion I completely forgot to un-trim. Bizarre, as I’m sure that I didn’t trim or split the edge! Perhaps it happened inadvertently!

Sach

Hi Sach - if the surface was ever joined to more than one edge along there, the edge would be split.

-Pascal

Yes, true. I did join I think but to an exact mirror so to exactly the same edge…

Sach Chauhan