GDL objects not showing separate materials when cut in 3d

[David Collins]

GDL objects created in ArchiCAD 17, such as this glass block coffer slab, are not showing the individual materials when cut in 3d. "Use Element Attributes" is selected in cutting plane menu, but the material noted in the "Model" section of the objects settings (under "Use Object's surfaces") is uniformly applied across the cut surface of the object.

Is this new behavior in 17 or has this always been the case? Is there a GDL command that would enable this?

[Laszlo Nagy]

If this is the case then the GDL Object is probably not scripted in a way to show these diffferent Building Materials.
As far as I remember it is the SECT_FILL command in GDL that you have to use to set the section fill you want the given geometry to use. You can then use the SECT_FILL command as many time as you want to switch.

So it goes like this:

SECT_FILL 1
  BLOCK 1, 1, 1 (will use fill 1 when cut)
  ADDX 1
SECT_FILL 2
  BLOCK 1, 1, 1 (will use fill 2 when cut)
etc...

[David Collins]

Thanks Laszlo.
SECT_FILL only defines the fills that appear in 2d sections cuts. (I think) The issue here is what happens when the object is cut in 3d.

I'm seeing the same behavior with standard library doors and windows. On the other hand, composite walls and slabs do show their separate skins in 3d cuts. I'm guessing this is the way its always been with library parts and I've only just noticed since 17 started showing us the skins of composite elements in 3d cuts.

[Laszlo Nagy]

Yes, you are right, those are only for Section/Elevation etc.

Well, the answer is that Building Materials (and Priority Based Connections, which is based on Building Materials) are not implemented in GDL-based element types. It is mentioned in this clip at about 1:27:

https://www.youtube.com/watch?v=fPlRm9nlpHg