Hidden object parameters

[Anonymous]

I am creating furniture objects wich should have "cost", "manufacturer","serial number " parameters.
I discovered that in the standard library some elements already have these parameters under gs_list variable.
So I thought it is a good idea to write my objects to be conform with the standard library. However when I tried to open a library part (for example sofa 04) I discovered that this gs_list variable is a special one. It cannot be leted . Can someone tell me the nature of this variable? Can I put this in my object? Is there a reason using/not using it?

ALso among list templeates I did not find a single list type which lists the COST of an elemnent. If there is not such list type how can I create one for myself?
Actually there is no explination in the manuals targeting this issue.
Regads,
Balázs

[Fabrizio Diodati]

Kedves Balasz,

the gs_list parameters come from the new sub-type concept: if you assign to your object a certain sub-type it inherits the parameters of that sub-type.
In your case, for example, the gs_list parameters immediately appear in your object ASAP you assign it the sub-type “Furniture”.

baratsaggal
Fabrizio

[Anonymous]

Köszönöm Fabrizio,

However I am curious, what is the advantage if I define my newly created object as, let's say furnitshing subtype, versus General GDL object.
Cheers,
Balázs

[Fabrizio Diodati]

Kedves Balasz,

I'm not a GS man (also if anybody in GSHQ knows me quite well!) so, of course, I cannot provide you the “official” answer.
I suppose this concept comes from the new IFC standard (GS is one of the main promoter of this Data Exchange Format) and I appreciated very much this choice!
Using sub-type is a way to standardize the library parts and better identify them.
Let to show me a simple silly example.
1. You, Balasz, creates a chair object in your office located in Budapest.
2. I, Fabrizio, develop a new ArchiCAD add-on that automatically put a needed number of chair all around a selected table.

With the new sub-type philosophy, I can say my add-on to let the user select each chair in the ArchiCAD library, not only those ones I released with my add-on.

If you save your chair as “simple General GDL Object” there is no way, for my add-on, to understand that it is a chair!
It cannot use the name to identify it… because my Italian add-on could looks maybe for the name “Chair” (for the English users), “Sedia” (for the Italian ones), “Stuhl” (for the Germans), “Silla” (for the Spanish) and “Chaise” (for the French) but the Hungarian language is too much difficult for it!

But, and this is the very interesting issue (!), if you save your chair, by using the proper sub-type (in this case “Furnishing/Seating”), my add-on will automatically recognize it as a chair!
The same “philosophy” is behind the ArchiCAD Accessory Tools.
The sub-type is a way to univocally “identify” an element.

Hoping I’ve been enough clear…

köszönöm szépen
baratsaggal
Fabrizio