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New face surfaces in SUBGROUPed GDL


These precast slabs are a single GDL object, a series of “concrete” PRISM_s for the slab themselves with “hard air” PRISM_s for the holes (hard air because I would like these slabs to subtract by material priority from any slab element which would be filling up their joints and producing a topping, and if I don't fill those holes that poured in place concrete appears filling the precast slab holes). 

Then the object has GDL solid geometry commands producing cuts for penetrations or irregular floor plan outlines. How can I get, with solid geometry commands, the cut face in the concrete slab to show as concrete, and the one in solid air to show as such (like what you get when using CUTPLANE). Using SUBGROUP I get both cuts to show as the material I set for the tool/operator/cutter. Slab and holes are being cut as a group, and I am hoping there is some way other than cutting concrete and air separately, after setting the tool/operator/cutter to the target PRISM_ material for each operation. 


Edit: or maybe for this kind of cuts it is better to just go CUTPOLYs.


SUBGROUP faces.png


Laszlo Nagy
Community Admin
Community Admin

This post gave me an idea.

I think, in theory, it would be possible to use the Curtain Wall Tool to model such Slab structures.

It is possible to create polygon-shaped Curtain Wall Panels as the "CW Polygonal Window 25" default library part proves it. So it would be possible to create a library part that uses a Profile defined in the Profile Manager Dialog, and cut it to the polygonal size of the Panel so achieve any panel geometry. All frames in this Curtain Wall would be invisible so we would only see the Panels modeling these prefabricated Slab panels.

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@Ignacio Sorry if I am missing the point of your post. The following was created with the beam tool for the precast slabs, Slab tool for the topping, Opening tool for the cut out and applying a SEO with downward extrusion with the slab as target & beams as operators. May save a lot of coding?


Screenshot 2022-01-30 at 15.05.06.png

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Well, the object does a lot more than the picture, and is way more powerful and capable than beam+SEO+opening, which is why I went GDL. [And it is not a lot of coding at all. Much less work than rearranging those beams during the design process of a single project. Or for that matter a single project phase. And I am using it on several projects.]

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