polygon extrude ( windows)

[BosPil]

when we created the tiles and windows. can we extrude the window polygon inside?

i dont want to use extruded cubes because thats a lot of extra polygons inside that i will never see.

[BosPil]

i found this in the paris project.

is this an option ?
Opening --> # opening is extrude, the comped, in Jouee (the sides) and the remaining extruded window
    extrude(DepthOpening)
    comp(f){side=reverseNormals Jouee. | top : reverseNormals Glass }

[MatthiasBuehler1]

exactly, use comp(f)

matt