Split face into rectangular pieces

[MagnusLundevall]

I have a planar face that I want to split along x into rectangular pieces, see enclosed figure. I have tried to examine the pivot pos of the edges with comp(fe) to find the x-positions for the split but without full success. 

Any suggestions for solution in CGA code? Is the question clear enough?

[ThomasFuchs]

Hello @MagnusLundevall 

Thanks for this interesting question. Please try this approach using comp(v) and sorting the vertices by their pivot.px

version "2022.1"

XPos = comp(v) { all : pivot.px }

SortedXPos = 
	XPos[sortIndices(XPos)]

const EPS = 0.01
calcNextVertexLoc(positions, i) =
	case i < geometry.nVertices:
		case abs(positions[i] - positions[0]) < EPS: calcNextVertexLoc(positions, i+1) // check next vertex position
		else: positions[i] - positions[0]
	else: scope.sx
	
getSplitPos =
	calcNextVertexLoc(SortedXPos, 2)

@StartRule
SplitRecursive -->
	split(x) { getSplitPos : Rectangle | ~1 : SplitRecursive }
	
Rectangle --> color(rand, rand, rand)

[MagnusLundevall]

Thanks for quick response. This is along the lines I have tried but much more elegant. It works in general but not for faces in certain orientations. I suspect I need to align the scope in some way. Any advice here?

To isolate the orientation problem I have made a simple shape where I try to apply SplitRecursive for each side face. Seems not possible to attach a scene here so I give the shape vertices instead. I have tried various kind of alignScope but without success.

@StartRule
Init -->
	comp(f) {side: SplitRecursive | all: NIL} 

Here is the current result. In this simple example I expect one Rectangle for each face.

[ThomasFuchs]

The approach only works for horizontal and planar Shapes like building footprints. The axis of pivot and scope must be aligned.

Generally, rectangles can be created with the innerRectangle operation.

[MagnusLundevall]

Oh, what a pitty. And there is no way to align the scope such that it can work?

I read about innerRectangle but don't see how it can be used to solve the example in the first post. Can you?