macroscript MakeRoadOnSurface category: "Generator"
(
fn s_filter o = superclassof o == Shape
fn g_filter o = superclassof o == Geometryclass
fn find_intersection z_node node_to_z =
(
 local testRay = ray node_to_z.pos [0,0,-1]
 local nodeMaxZ = z_node.max.z
 testRay.pos.z = nodeMaxZ + 0.0001 * abs nodeMaxZ
 intersectRay z_node testRay
)
on isEnabled return selection.count > 0
on Execute do
(
	target_shape = pickObject message:"Pick Target Shape:" filter: s_filter
	target_mesh = pickObject message:"Pick Target Surface:" filter:g_filter
	if isValidNode target_mesh then
	(
		undo "MakeRoadOnSurface" on
		(
			sweepMod = sweep()
			modPanel.addModToSelection sweepMod
			sweepMod.shapes[1] = target_shape
			sweepMod.CustomShape = 1
			macros.run "Modifier Stack" "Convert_to_Poly"
			for i in $.verts do
			(
				int_point = find_intersection target_mesh i
				if int_point != undefined then
				(
					if int_point.pos.z > 0 then
						i.pos = int_point.pos + [0,0,10]
					else
					(
						i.pos.z = 0
					)
				)
			)
		)
	)
)
)