GDL language - should I use it at all?

[cocoloco]

Hi! Is there someone here who understands GDL language? I usually model my own products, but I was curious to try modeling via GDL with my friend ChatGPT,  and it didn’t go well.

As you can see, GDL is not my strength and I honestly don’t really know how it works, and wanted to test it if it would save some time - so please bear with me.

I’m just curious if it can model anything at all. I tried creating an oval table with a full bullnose top and cylindrical legs. But every time I added the script as a new object, it gave me an error — line by line — always saying “MISSING CALL.” Fix one line, and then another line would trigger the same error. Nightmare. How is this legal to work this bad? why not to say all the errors at once?

Anyway, in the end, it was recommended that, for an oval table with a bullnose top and cylinder legs, it’s actually better to leave the GDL scripting (LOL) and instead:

• Use the Archicad Object Tool wizard to create a parametric block + cylinder table interactively rather than hand-coding.

• Set all parameters (width, depth, height, tabletop thickness, leg diameter, leg offset) directly in the UI.

• This avoids all MISSING CALL or sweep2 issues and ensures the object is fully adjustable in the Settings dialog.

Is there someone here who knows GDL and can confirm whether it really has these limits? Am I better off modeling objects the way I usually do? What is the gdl language used for then? 

[Laurentiu]

Yes, there are quite a few people who understand GDL.

Specific GDL questions are posted in the Developer Hub > GDL section of the community, take a look there.

I don't think chatGPT knows that much about GDL, mostly because I don't think it has that many available resources to train it off. Last time I tried it just spilled so much gibberish I gave up in like 5 minutes.

I'm not amazing at it myself or anything, but I have learned a lot in the last year and I can honestly say it's a powerful skill to have as an Archicad user and it allows you to at least have clean objects even if they are custom.

If you're curious about how it works and want to learn more, here are some resources to get you started.

BarkingDogBIM < go from the very first video and start there.

MF BIM < a short table tutorial in 8 parts, you can do this in parallel with the first link.

Make Parametric Objects in Archicad with GDL course < this is a paid course on udemy that is 100% worth it. You get to go from 0 to very complex objects and are guided all the way through gradually.

Other resources:

GDL Center

Object making with Archicad

GDL Cookbook 4

[Barry Kelly]

Every object, door and window you use from the library is scripted in GDL.

So it can certainly do a lot of things.

However, if you want to script properly, you need to learn how to do it.

There have been many posts here over the years about "how do I learn GDL".

You can of course just model elements and save them as an object, door or window.

This will automatically create a script, but the object will not be parametric (stretchy or changeable).

And it will not be a script that is easily editable to make it parametric.

It is a long learning process, so be warned.

Barry.

[Lingwisyer]

Regarding the attempt to code a table, there was an old GS GDL Tutorial that was about making a table. Will see if I can locate it later...

Ling.

[scottjm]

If you want custom static objects and don’t know GDL it’s easiest to model with native tools and objects, moorish etc to make what you need. 

if you want to create fully parametric objects GDL is extremely powerful. I would call it a super power of Archicad, but GDL is not accessible if you don’t know how to code. 

Unfortunately it will take time to learn how to write GDL, if you have previous experience it will come naturally, but if you don’t it’s a long road.  @Bruce ’s youtube guides are an excellent series to start to learn  GDL. 
https://youtube.com/@barkingdogbim

[Ahmed_K]

I share the same doubts with you, should i learn gdl ? Is it really a good thing that will accelerate my workflow ? The answer is not a simple yes or no, 

First of all, Why gdl ?

The main response is : 1 source objects, different shapes using parameters, 

The strength in this is that i can have a schedule of a tables with extracted parameters from different parts, without the need of modelling various dumb tables .

Or extract that parameters with labels, at the end instead of modelling multiple dumb objects, you start from 1 object, and create smart customised instances .

In my daily workflow, 99% of my schedules don't extract gdl parameters except of doors and windows, i use the default doors and windows and it's d

Good for most of the cases.

So i abandoned learning gdl, the default library objects can do the job, if i need a custom object, i can import it as a dumb object, and i'm sure i won't even need to schedule it, and if it happens, i use custom properties.