Bug with the extend surface command

Hi there. Currently using Rhino for Mac 6 and there appears to be a bug in it with the extend surface command on already trimmed surfaces that is driving me batshit crazy.
This is on regular shaped surfaces with a continuous edge that is trying to be extended. Most time I try and extend a surface, the thing goes the other way and shortens the surface. I’m currently working on an Alloy Boat design that is requiring a lot of modification. 5 minute job (not really) in Rhino 5 OSX as all I’m doing is re trimming or extending existing surfaces in an existing design. With this Bug I’m having to literally take a border of the existing surface, Untrim the surface, redraw the border and then re-trim the surface to the new outline. This is on regular rectangular surfaces with the edge desired to be trimmed, being a continuous edge along its length.
The same model & same surfaces in Rhino 6 for PC is not appearing to do the same

Can you post a sample surface?

sample surface.3dm (311.6 KB)
See attached. This same surface when I try and extend the left end, in Rhino 6 for PC, extends the input distance, in the case of this particular surface I was trying to extend it 30mm. Menu - Extend Surface (or selecting from surface tools) - pick surface end - input 30mm - success
Same surface in Rhino OSX, using same method, the surface shortens by 30mm. Will not lengthen the surface >50% of the time I try and use the command.

Point of note, I am modifying an existing design, I cannot definitely say how the surfaces were created.

Hello - please try UntrimAll on the surface and see how it works after that (I do not have access to a mac at the moment, but I’ll test this)
Also please post the service release of the Mac version you’re using (SystemInfo command)


Hi. Been there, done that. Whole point of the issue the bug is creating is I am trying to avoid doing that in order to work with some relative efficiency and Rhino 5 OSX and Rhino 6.0 PC is allowing me to do so. The bug, if it is one seems limited to Rhino 6 OSX.

System Info
Rhino 6 SR17 2019-8-24 (Public Build, 6.17.19236.01022, Git hash:master @ 06b69c5cc21d880aa793a5a7cfd454a66f6213bb)
License type: Evaluation, build 2019-08-24
License details: Stand-Alone
Expires on: 2019-10-26

Apple Intel 64-bit macOS Version 10.14.6 (Build 18G95) (Physical RAM: 16Gb)
Mac Model Identifier: Macmini7,1
Machine name: Simon’s Mac mini (2)
Language: en-AU (MacOS default)

Intel Iris OpenGL Engine (OpenGL ver:4.1 INTEL-12.10.12)

OpenGL Settings
Safe mode: Off
Use accelerated hardware modes: On
Redraw scene when viewports are exposed: On

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

Vendor Name: Intel Inc.
Render version: 4.1
Shading Language: 4.10
Maximum Texture size: 16384 x 16384
Z-Buffer depth: 24 bits
Maximum Viewport size: 16384 x 16384
Total Video Memory: 1536 MB
Graphics: Intel Iris
Displays: PHL 273V5 (82dpi 1x)

Graphics processors
Intel Iris (1536 MB)
PHL 273V5 (1920 x 1080 @ 60 Hz)

USB devices
GenesysLogic: USB3.0 Hub
Seagate: FreeAgent GoFlex
Logitech Inc : Logitech USB Headset H540
PixArt: Microsoft USB Optical Mouse
Apple, Inc.: IR Receiver
Apple Inc.: Bluetooth USB Host Controller
Logitech: USB Receiver

Bluetooth devices
Apple: Apple Wireless Keyboard

Third party kernel extensions
com.kaspersky.kext.klsat (1.0.1a2) 58F200A6-265B-3863-89D2-D657BA34AF2C
com.kaspersky.kext.kimul (46) A8797394-1582-3199-B848-57168A700E56
com.kaspersky.kext.klif (3.6.12a2) 6BA1AFA7-F84D-3C69-9E56-0C3E21139D2E
com.kairos.driver.DuetDisplay (1) EBD32AC4-5147-35AE-9FA3-8B8BB38E4FBA
com.kaspersky.nke (2.4.0a6) 45D3BCC3-2FB1-37A1-8148-801CBB1D353B
com.google.drivefs.filesystems.dfsfuse (33.0.16) 478AED06-D747-34F7-8930-927A0553849C
com.devguru.driver.SamsungMTP (1.4.31) A7E0B5D7-7F18-FF68-E78D-8B807B44F6CF

Third party plugins

Rhino plugins
/Applications/Rhinoceros 6.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/RhinoCycles.rhp “RhinoCycles” 6.17.19236.1022
/Applications/Rhinoceros 6.app/Contents/PlugIns/NamedSnapshots.rhp “Snapshots” 6.17.19236.1002
/Applications/Rhinoceros 6.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/GrasshopperPlugin.rhp “Grasshopper” 6.17.19236.1022
/Applications/Rhinoceros 6.app/Contents/PlugIns/PanelingTools.rhp “PanelingTools” 6.17.19236.1002
/Applications/Rhinoceros 6.app/Contents/PlugIns/AnimationTools.rhp “AnimationTools” 6.17.19236.1002
/Applications/Rhinoceros 6.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/Commands.rhp “Commands” 6.17.19236.1022
/Applications/Rhinoceros 6.app/Contents/PlugIns/SolidTools.rhp “SolidTools” 6.17.19236.1002
/Applications/Rhinoceros 6.app/Contents/Frameworks/RhMaterialEditor.framework “Renderer Development Kit” 6.17.19236.1002
/Applications/Rhinoceros 6.app/Contents/PlugIns/import_ACAD.rhp “AutoCAD file import: import_ACAD” 6.17.19236.1002
/Applications/Rhinoceros 6.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/RDK_EtoUI.rhp “RDK_EtoUI” 6.17.19236.1022
/Applications/Rhinoceros 6.app/Contents/PlugIns/Displacement.rhp “Displacement” 6.17.19236.1002
/Applications/Rhinoceros 6.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/RhinoDLR_Python.rhp “IronPython” 6.17.19236.1022
/Applications/Rhinoceros 6.app/Contents/PlugIns/RhinoRender.rhp “Rhino Render” 6.17.19236.1002