Flat roof parapet walls

[NikolaiMina]

Hi everyone. I'm new to CGA rules and trying to make a simple parapet wall around a roof deck but I can't do it properly. Here's what I got so far:

Lot-->

extrude (4)

comp(f) {

side: Facade | top: Roof1}

Roof1--> 

split(x) { ~0.5 : Block | ~0.5 : Deck}

Block-->

extrude(3)

label("Block")

Deck-->

offset(-0.2)

comp(f) {border: Parapet}

Parapet-->

extrude(1)ParapetWall

ParapetWall -->

case touches(intra, "Block") : 

                               NIL

                 else : Wall.

Thanks in advance!

[plfontes · Accepted solution]

Hi @NikolaiMina,

I am assuming you are referring to the parapet side being cut in diagonal on the side it touches the 'Block'

This happens because of the way trim planes are set in CE.

When you set your occlusion operation, it just don't execute the 'ParapetWall' rule. The offset operation that generated the inital shape for the parapet border isn't affected.

One alternative way to avoid  the parapet gap is to create a 'border' on three side only using the split operation.

version "2023.0"

Lot-->
	extrude (4)
	comp(f) {side: Facade. | top: Roof1}
 
Roof1--> 
	split(x) { ~0.5 : Block | ~0.5 : Deck}

Block-->
	extrude(3)
 
Deck-->
	split(x){ ~1: split(y){0.2: Parapet | ~1: DeckFloor. | 0.2: Parapet} | 0.2: Parapet }
 
Parapet-->
	extrude(1)

Hope this is what you were referring to.

[NikolaiMina]

Yes, I was referring to the diagonal gap (sorry I should have been more specific). Thanks for the explanation!