Grasshopper to ARCHICAD: Translation Challenges 01

 In BIM, Data, Design, Grasshopper

Hello everyone,

I think lately a huge amount of ARCHICAD users, and I include myself, have been exploring and playing around with the connexion in between Rhino Grasshopper and ARCHICAD. Graphisoft in my opinion has been doing a great job making tutorials and exercise about how to use this connexion. One of the most interesting aspects of the connection is the possibility of controlling GDL parameters of the objects we create. I think we have only started to scratch the surface of this workflow..

But what happen when we want to import to ARCHICAD elements we have model in Rhino using Grasshopper? If you have ben using the connexion already probably you realise that the elements in ARCHICAD have a particular way of being imported from Grasshopper scripts. Walls, Slabs, Beams, Columns, etc.. all of them need a particular set of inputs. Unless we understand the inputs we need we will not be able to “model” in ARCHICAD using Grasshopper. If you follow Graphisoft tutorials and exercise it is quite simple to understand this concept.

Lately we have been implementing ARCHICAD in an office that is used to work in Rhino and Grasshopper. So what they expected from us is to convert the model the had in Rhino into an ARCHICAD file. They thought it was going be something like one single click, but the reality is that we needed to script a little to “translate” the geometry from Grasshopper to ARCHICAD. This situation is very common when you start learning Grasshoper as well. You may see a lot of amazing tutorials and then after completing the exercise you may be like “how the hell do I bring that to ARCHICAD now?”..

It is just a matter of adapting the Grasshopper Scripts to give you the data that you need. The more complicate the script is the more complicated it may look like. But you just need to organise in a logic way how your elements will be translated in AC and then understand what these elements are demanding as inputs.

I want to explain this issue with an exercise I just learned from youtube. In this easy 8 min tutorial from a youtube channel called OM I learned a script that I wanted to use in ARCHICAD as a method of create a ceiling. This is the link to the tutorial. It is called “Grasshopper tutorial Curve attractor”.

I strongly recommend you to try this tutorial yourself. This channel has a great deal of short exercise that will allow you to explore RH – GH in a very easy way.

But my challenge was to translate these geometries into AC native elements. How shall we do it?

Let’s get started..

One very easy option would have been use just Morphs of course. But looking at this vertical elements I thought that the correct choice was to use “Columns”. The result of the script in GH that we obtain after reproducing this tutorial is basically a set of “Extrusions”.

How to convert these extrusions into columns?

I recorded my own short tutorial to show how to translate this exercise into AC. In my video I start from the script already finished of the video tutorial “Grasshopper tutorial Curve attractor”. So in the 5 minute tutorial I prepared I basically make a short script to bring my geometries we heritage (extrusions) into columns in AC. It actually takes only 3 minutes, the rest of the video is to how how cool is to have the documentation and schedules updated automatically as we modify the script in GH..

The steps of the video are as follows:

1. We start with the existing script that we created from the “Grasshopper tutorial Curve attractor”. We will start extracting data from this script to develop our’s and bring these elements into AC.

2. First of all we create the new commands we need to set up our “columns”.

3. The challenge starts: We need to create the set of points that will be our “end points” for the columns. For this purpose we will need a few steps to compose our script. We will use the data from the “ReMap” command to vary the vertical movement of our set of points. We will also use “Extrude” command that we already set in our existing code.

4. Now we need to create the set of points that will be the “anchor points” for our set of columns. We will extract the data we need from the “area” command that we also had already from the previous exercise. With both set of points, “anchor and end” we can define our columns.

5. In the column settings command we will have to input the two commands for the dimensions also from the “ReMap” command. In this way these values will also follow the proportional scale based on the proximity to the curve.

6. Activate the connexion from the AC file and set “true” the value that controls the column command.

7. Modify the values and the geometry of the curve in Rhino to see how the whole group of columns adapt in real time. Our Sections, elevations, Floor plans and Schedule will follow and update automatically.

So in this short exercise we learned how to bring a set of geometries that originally were “extrusions” into “columns” in our ARCHICAD model. This mean that from any script source that we use, we will have to extract or reproduce always a set of points for the base of the column and a et of points for the end. As I mentioned previously if you are already using the connexion in between AC and RH – GH you will face this kind of situations in which you have to bring complicated geometries into AC. Is good to understand which  one is the best way to do this so your model can be logic an useful.

We will keep up exploring how to bring cool stuff from RH – GH to ARCHICAD and get the BIM out of it.

I hope you find this article – tutorial interesting! Please feel free to leave any comment or question.

Thanks for reading us!

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