Thursday, 24 December 2009

BullAnt Contouring Colors

This screen capture quickly demonstrates the BullAnt command ggContour to apply a spectrum color range to subLayers of active layer. By typing the command, you can nominate to apply it to Rhino objects in a model (based on sequence of creation/modification or selection depending on how you pick the objects). Download the plug-in from

Wednesday, 23 December 2009

Orienting Structure to Rhino Surfaces

Here's an example/tutorial for you to follow to use the plug-in to calculate member orientation angles based on the defining surface normal or nearest point.

To try this yourself, here is the Rhino file: Rhino Ellipse

Now the same basic procedure will work presently with 3 analysis packages, GSA, Sofistik (shown) and SAP2000. Strand7 and others coming shortly.
Here's the analysis models:
Sofistik (Note LOCA 0 is assumed for the moment.)

More instructions coming soon....

Monday, 21 December 2009

Controlling GSA from a Rhino Plug-in

There's been a few requests for help with controlling Ansys from Grasshopper or Rhino on the Rhino newsgroup or Grasshopper forum lately, and in my discussions with them, it's generally been agreed that for a skeletal frame, it's likely to be easier and quicker to use a frame analysis program like GSA to do the exercise. (Possibly influenced by my limited experience with Ansys, which is an amazingly capable but complex analysis program).

GSA have a free version for any academics or students, refer

And to assist with getting started, I created a small Rhino Plug-in project that generates a GSA model from scratch and runs an analysis.

Download source code :

If you have GSA running, you can supervise and interact with the program after execution. If GSA is not running, it will run as a background process.

If you're looking for the GWA data on the rhino model objects created using the SSI tools, try using the command GetUserText (or the user string attributes in the Rhino SDK). I'll improve the event watcher shortly so that GWA node coordinates are updated when a node is moved.

This is just the start of interaction with Rhino, there's another level of using the Plug-in code as a library. Feel free to get in touch if you wish to learn more.

Tuesday, 1 December 2009

Weaire-Phelan intersecting a surface

I responded to a request for help on the Grasshopper forum with regards to generating Weire-Phelan polygons intersecting with a surface. I've recorded the screen capture below showing the difference as you halve the size of the polygons which I think is quite interesting. If you wish to try for yourself, the Rhino file can also be downloaded below, could be interesting to see how other shapes look (and to generate the intersecting curves using the command in the BullAnt plug-in)

Associated Rhino File