While experimenting Section tools for dynamic drafting, I ran into an issue with dimensioning. Radial dimension commands (DimRadius / DimDiameter) do not select displayed circles and arcs in the section created drawings.
Is there any supported workflow to dimension sectioned circular geometry, or is this a current limitation at this point? Really appreciate in advance for any further information.
Hi Bimo -
In a quick test here, that seems to be working as expected.
Please post both the output from the Rhino SystemInfo command and a 3dm file that is giving you issues.
-wim
Hi @wim Really appreciate your kind reply.
Rhino 8 SR34 2026-8-11 (Rhino 8, 8.34.26223.11001, Git hash:master @ f416e902495235e4e4a45cfc29ff1320cc8c70d8)
License type: Not For Resale Lab, build 2026-08-11
License details: Cloud Zoo
Windows 11 (10.0.26200 SR0.0) or greater (Physical RAM: 80GB)
.NET 8.0.27
Computer platform: LAPTOP - Plugged in [90% battery remaining]
Non-hybrid graphics configuration.
Primary display and OpenGL: AMD Radeon™ Graphics (AMD) Memory: 16GB, Driver date: 7-22-2025 (M-D-Y). OpenGL Ver: 4.6.0 Compatibility Profile Context 25.10.16.01.250721
Integrated accelerated graphics device with 5 adapter port(s)
Integrated accelerated graphics device with 5 adapter port(s)
Secondary graphics devices.
NVIDIA GeForce RTX 3060 Laptop GPU (NVidia) Memory: 6GB, Driver date: 8-7-2025 (M-D-Y).
Integrated accelerated graphics device with 4 adapter port(s)
OpenGL Settings
Safe mode: Off
Use accelerated hardware modes: On
GPU Tessellation is: On
Redraw scene when viewports are exposed: On
Graphics level being used: OpenGL 4.6 (primary GPU’s maximum)
Anti-alias mode: 2x
Mip Map Filtering: Linear
Anisotropic Filtering Mode: High
Vendor Name: ATI Technologies Inc.
Render version: 4.6
Shading Language: 4.60
Driver Date: 7-22-2025
Driver Version: 32.0.21016.1010
Maximum Texture size: 16384 x 16384
Z-Buffer depth: 24 bits
Maximum Viewport size: 16384 x 16384
Total Video Memory: 57220 MB
Rhino plugins that do not ship with Rhino
C:\Users\Personal\AppData\Roaming\McNeel\Rhinoceros\packages\8.0\ProRender\1.0.1.5\ProRender.Windows.rhp “ProRender” 1.0.1.5
C:\Users\Personal\AppData\Roaming\McNeel\Rhinoceros\packages\8.0\rhinomcp\0.3.2\net8.0\rhinomcp.rhp “rhinomcp” 0.3.2.0
Rhino plugins that ship with Rhino
C:\Program Files\Rhino 8\Plug-ins\Commands.rhp “Commands” 8.34.26223.11001
C:\Program Files\Rhino 8\Plug-ins\rdk.rhp “Renderer Development Kit”
C:\Program Files\Rhino 8\Plug-ins\RhinoRenderCycles.rhp “Rhino Render” 8.34.26223.11001
C:\Program Files\Rhino 8\Plug-ins\rdk_etoui.rhp “RDK_EtoUI” 8.34.26223.11001
C:\Program Files\Rhino 8\Plug-ins\NamedSnapshots.rhp “Snapshots”
C:\Program Files\Rhino 8\Plug-ins\MeshCommands.rhp “MeshCommands” 8.34.26223.11001
C:\Program Files\Rhino 8\Plug-ins\RhinoCycles.rhp “RhinoCycles” 8.34.26223.11001
C:\Program Files\Rhino 8\Plug-ins\Grasshopper\GrasshopperPlugin.rhp “Grasshopper” 8.34.26223.11001
C:\Program Files\Rhino 8\Plug-ins\Toolbars\Toolbars.rhp “Toolbars” 8.34.26223.11001
C:\Program Files\Rhino 8\Plug-ins\3dxrhino.rhp “3Dconnexion 3D Mouse”
C:\Program Files\Rhino 8\Plug-ins\Displacement.rhp “Displacement”
C:\Program Files\Rhino 8\Plug-ins\SectionTools.rhp “SectionTools”
====================
I’m also attaching screen recording to show exactly how I couldn’t select the circle created by section.
Again, really appreciate the time and help.
You might try updating your video drivers and switching your primary video to the Nvidia and see if that helps.
Hi Bimo -
In Rhino 8, the layers that are created by the ClippingDrawings command are automatically locked. Since you apparently can create aligned dimensions by snapping to end points, you likely have the “Snap to locked objects” option turned on. That only does what that says. To create a radial dimension, you need to be able to pick an edge. For that, you need to unlock the layers.
-wim
Hi @wim
Really appreciate the effort and time to explain things.
I had turned on the “Snap to locked objects” and still, when the particular layer is locked, it can not recognize the circle or arc curve, other than end point, knot, quad, etc.
The specific rad and dia with snap enabled, is just always a miss. Even when I tried to place centermark, it failed. It could be a “miss”, not a bug 
Is it possible to report this as a additional request when it’s a true miss?
When every other thing just works, recognizing circle or arc doesn’t seem to.
Hi @AlW. Really appreciate the suggestion. Had tried to change other than ISV and WHQL drivers but the issue doesn’t seem to be happening from the driver. Rolling back to the one that I’ve been using without provlem. I even changed between NET CORE and Framwork. That didn’t solve the issue either.
Hi Bimo -
That’s what I tried to convey, yes.
For those specific dimension types (radius and dimension, but also angle, curve length, area, and volume), you need to be able to pick geometry. Not just be able to snap to it. This means that you need to unlock the layer.
In Rhino 9, it’s already possible to pick locked geometry when creating annotations …
… except for the centermarks.
RH-98242 Centermark: Allow Selecting Locked Objects
-wim
Great thanks, @wim
Really appreciate the time Will move forward based on the explanation you gave.
Really appreciate it, @brian. Was playing with R8 and will try in R9 Beta