On Land

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At Rill Architects we run ArchiCAD on macOS. If you work at Rill, this is your stuff. If you don't, but you work in ArchiCAD, you may find something interesting. Anybody else, I don't know.
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AC11 has a model view option to put the floor plan into reflected ceiling mode. It only works for objects, not regular elements (wish wish wish). I have several objects that take advantage of it.

This is the basic code you need to have a symbol draw itself differently in floor plan and RCP mode. The idea is that depending on the state of the switch, you set certain attributes, draw some things and not others, etc. Often, the shapes are the same, but the line switches from dashed to solid; stuff like that.

!! Parameters
!! plnPen : Plan Pen (0=Match)
!! plnLT : Plan Linetype (0=Match)
!! rcpPen : RCP Pen (0=Match)
!! rcpLT : RCP Linetype (0=Match)

!! If attributes are 0, set them to object settings
IF rcpPen=0 THEN rcpPen=L_
IF rcpLT=0 THEN rcpLT=SYMB_LINETYPE
IF plnPen=0 THEN plnPen=L_
IF plnLT=0 THEN plnLT=SYMB_LINETYPE

!! Request state of ceiling switch
rr=REQUEST("floor_plan_option","", storyViewpointType)
!storyViewpointType=1 !! testing

IF storyViewpointType=1 THEN !! ceiling
	!!Set ceiling attributes
	PEN rcpPen
	LINE_TYPE rcpLT
	!! Draw ceiling-only parts
ELSE !! floor plan
	!!Set floor plan attributes
	PEN plnPen
	LINE_TYPE plnLT
	!! Draw floor-plan-only parts
ENDIF

!! Draw parts common to both plans, using whichever attributes
LINE2 ...
RECT2 ...
POLY2 ...