Which file type contains parameters/features/parameterisation among .gh or .ghx or other cadfile (.igs, .step,...?)

Hi all,

Basically, I am trying to import a model (generated by Rhino/Grasshopper) and perform FEA (ABAQUS)and optimisation (Isight, Dassault system). Importing the model into Abaqus and performing FEA was okey. But a problem is, once finished FEA, Isight software cannot detect any parameters/features of the model so it was unable to pick up input variables. Therefore, as a possible solution, what I am thinking is to build a python (or matlab) script to fill the gap between Rhino/G.H and Isight. This means that the python script can make Isight picks up parameters of the model generated from Rhino/G.H

As far as I know, exporting rhino file into .igs, .step file lost all parameters/features. Then I guess there is a possibility of using .gh file or .ghx file which it seems like it contains all parameters/features.

To summarise my question,

  1. Does either of .gh file or .ghx file contain all parameters/features of the model?
  2. Or any CAD file type (3dm, .igs, .stp, .COLLAD…) has features when they get exported?
  3. If so, one of two questions, is it possible to build a python script to import the model with all parameters?

I don’t really know what ‘parameters/features’ means exactly, so this answer may not be helpful.

The .gh and .ghx files contain the components, their connections and whatever persistent data has been set by the user. These two file types contain the exact same information, but one is binary and the other xml. You could parse the xml directly, or you could use GH_IO.dll to read gh files in a type-safe manner. Do note that unless you also load Grasshopper and all GHA plug-ins, you cannot execute any of the components, since the code which actually runs is not included in the files. All you can do is tell which components there are, not what they are supposed to do.

The other file formats you mentioned are all quite similar, they are basically just tables of geometry and attributes.

So the question is, what data exactly does Isight need to work? Meshes? Isight objects? A BIM database?

Hi David

Thank you for the comment, the data Isight needs are ‘parameters’. Let’s say there is a 3D box, in this case, parameters will be height of the box, width and length of the box. hopefully, it helps you.

To be honest, I could not really understand your comment but it seems like there must be a GH_IO.dll to make gh file readable. Is it right? In my brain, I made an assumption that python script can “read” all parameters which are from .gh or .ghx file…uhm… to be honest, can you please explain more easily the first paragraph? I am really new at G.H

Thank you in advance…

And these parameters are formatted how?
And what about shapes other than boxes?


Box looks like the uploaded picture.
Parameters mean the value of ‘height’, ‘width’, and ‘length’ so 5=width 2=height 10=length
Features mean ‘plane surface’ and ‘extrude’ this case.

So what I wonder is

  1. .gh or .ghx file containing these ‘parameters’ and ‘features’ both?
  2. if not, when Rhino exports this Box (after bake), does any file contain these ‘parameters’ and ‘features’ both? (for example, IGES and STEP file format does not have the CAD data)

Hello, do you know how to integrate Rhino into iSIGHT? I also want to do relevant research, I hope you can tell me.


All features are lost after the creation of geometry.