Unselectable Geometry. Bug or Other?

I’ve got a geometric situation resulting from a Mirror and Extrude Surface process. In certain views, I can see the mirrored geometry, but not select it. Is this a bug or is there some other way to handle this? ~Dave

Flower_Unselectable_Geometry.3dm (2.9 MB)

Software information

Software versions
Rhinoceros version: 5.0.2 (5A865)
IronPython version: 5.1.2015.131
Language: en (MacOS default)
OS X version: Version 10.10.4 (Build 14E46)


Third party kernel extensions
com.Logitech.Control Center.HID Driver (3.9.1)
com.Logitech.Unifying.HID Driver (1.3.1)
org.virtualbox.kext.VBoxDrv (4.3.20)
org.virtualbox.kext.VBoxUSB (4.3.20)
org.virtualbox.kext.VBoxNetFlt (4.3.20)
org.virtualbox.kext.VBoxNetAdp (4.3.20)

Hardware information

Computer hardware
Hardware model: MacBookPro8,3
Processor: Intel Core i7-2860QM CPU @ 2.50GHz
Memory: 16 GB
Architecture: Intel 64 bit

Video hardware
Graphics: AMD Radeon HD 6770M 1024 MB
Memory: 1024 MB
Screen size: 1920 x 1200
Displays: Color LCD (133dpi 1x)

USB devices
Apple Inc.: FaceTime HD Camera (Built-in)
Logitech: USB Receiver
Apple Inc.: Bluetooth USB Host Controller
Apple Inc.: Apple Internal Keyboard / Trackpad
Apple Computer, Inc.: IR Receiver

Bluetooth devices

OpenGL information

OpenGL software
OpenGL version: 2.1 ATI-1.32.24
Render version: 2.1
Shading language: 1.20
Maximum texture size: 16384 x 16384
Z-buffer depth: 24 bits
Maximum viewport size: 16384 x 16384

Implementation settings
Use texture compression: No

Appearance settings
Antialiasing: 6x
Mip map filtering: None
Anisotropic filtering: High

Try SelBadObjects… The surface is invalid, it has (according to Check) “no edges”.

Not sure what you can do to fix it, but at least you can delete it that way.

Oh, and it would be good to have a “recipe” for reproducing this as it should not really happen…


Thanks, Mitch! (I knew there was a command to find a problem surface, but couldn’t recall it.)

Recipe File (Attached):
Unfortunately, repeating the steps with this geometry (placed in a new file) does not re-create an Invalid Surface. In the image attached, you can see the options chosen for the final step (OffsetSrf) in this file.

Original File with Invalid Surface:
In the original problem file, before I got the invalid surface, I performed several different OffsetSrf commands, seeking the desired result. The three variables I altered (in several iterations) were: Round corners, Flip, and a larger offset distance. I believe I simply issued an Undo command after each undesired result, then tried again. After several tries, I got the desired form, but an invalid (and un-selectable) surface on the mirrored side.

As for the original surface in Step One, this was created with a Sweep2 (the long curves as rails) and a number of Slashes were inserted.

Not sure if any of this helps, since I can’t recreate the problem, but something definitely went awry originally.


Flower_Unselectable_Geometry.3dm (2.9 MB)