Newbie to editing surfaces

Hello can you help me? I am trying to design some buildings on a hillside.
The hillside was created as a polysurface with the patch command.

I want to put some buildings on the hill. So what is the best way to do this? obviously the hillside will have to be terraced into flat planes to take the buildings.

I thought I could draw the building in plan form using curves. Then use Project command onto surface. Then what to do? I surely need to cut out the projected plan on the poly surface. And then draw a flat surface.

So I have tried trim, split and split using isocurve to cut hole in polysurface. None seems to work.
What would be the best approach to this?


Hello - please post a simple example of what you are trying to do.


I have sent the file to

Hello I am working on a urban design project and I plan to rebuild the hillside using contours.
I am trying build off the plan. Here I show two images one with the model set to wireframe and one rendered.
The 2d drawing which the 3d model is based on is only partly visible in the rendered version. Why is that ? I don’t think I am so absent mined that I created some sort of object and left it there obscuring the view. Using select command I cannot find any object hiding my view. So what is going wrong?
I also need to draw contours at the correct height. I realise that Rhino works on C planes not wcs and ucs like AutoCad. However if you do a a point command under analyse, the points x,y and z values are given as world coordinates and c plane coordinates.
Is it possible to turn on some sort of origin marker for these two coordinate systems like wcs and ucs in AutoCad?

I assume gumball does not do this because it always relocates to whatever object you have just selected

Hello - you can set custom CPlanes (CPlane commanmd) and save them with NamedCPlanes.


Sorry here are images relating to first part of post aboveUrban design rendered|690x420

Hello - I have your file here and I do not see that so far - can you please run SystemInfo in Rhino and copy/paste the results here?


Rhino 6 SR34 2021-2-3 (Rhino 6, 6.34.21034.07001, Git hash:master @ 2fec8130f097ca52a8bc9f334c3ed4a5921c5e30)
License type: Educational, build 2021-02-03
License details: Cloud Zoo. In use by: Kieran Gallagher ()

Windows 10.0.0 SR0.0 or greater (Physical RAM: 7.8Gb)
Machine name: DESKTOP-CFBSL2B

Computer platform: LAPTOP - Unplugged [94% battery remaining] ~162 minutes left

Standard graphics configuration.
Primary display and OpenGL: Intel® UHD Graphics 620 (Intel) Memory: 1GB, Driver date: 4-11-2020 (M-D-Y). OpenGL Ver: 4.6.0 - Build
> Integrated graphics device with 3 adapter port(s)
- Windows Main Display is laptop’s integrated screen or built-in port

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: High

Vendor Name: Intel
Render version: 4.6
Shading Language: 4.60 - Build
Driver Date: 4-11-2020
Driver Version:
Maximum Texture size: 16384 x 16384
Z-Buffer depth: 24 bits
Maximum Viewport size: 16384 x 16384
Total Video Memory: 1 GB

Rhino plugins
C:\Program Files\Rhino 6\Plug-ins\Commands.rhp “Commands” 6.34.21034.7001
C:\Program Files\Rhino 6\Plug-ins\WebBrowser.rhp “WebBrowser”
C:\Program Files\Rhino 6\Plug-ins\rdk.rhp “Renderer Development Kit”
C:\Program Files\Rhino 6\Plug-ins\RhinoScript.rhp “RhinoScript”
C:\Program Files\Rhino 6\Plug-ins\IdleProcessor.rhp “IdleProcessor”
C:\Program Files\Rhino 6\Plug-ins\RhinoRender.rhp “Rhino Render”
C:\Program Files\Rhino 6\Plug-ins\rdk_etoui.rhp “RDK_EtoUI” 6.34.21034.7001
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\Alerter.rhp “Alerter”
C:\Program Files\Rhino 6\Plug-ins\RhinoCycles.rhp “RhinoCycles” 6.34.21034.7001
C:\Program Files\Rhino 6\Plug-ins\Toolbars\Toolbars.rhp “Toolbars” 6.34.21034.7001
C:\Program Files\Rhino 6\Plug-ins\3dxrhino.rhp “3Dconnexion 3D Mouse”
C:\Program Files\Rhino 6\Plug-ins\Displacement.rhp “Displacement”

Hello - please turn off the ground plane in the rendered view (Ground plane panel) - does that do it?



Yes that works…thanks

Sorry do you have a video clip showing me how to carry out the C plane command

Hello - start the CPlane command and then tap the F1 key for the Help on that command.