Carts: Check for last pathfinder predition too

Minor fix to reduce cart jitter slightly

mods/carts/functions.lua

@@ -159,23 +159,29 @@ function carts:get_rail_direction(pos_, dir, ctrl, old_switch, railtype)
end

function carts:pathfinder(pos_, old_pos, old_dir, ctrl, pf_switch, railtype)
	if vector.equals(old_pos, pos_) then
		return true
	end

	local pos = vector.round(pos_)
	local pf_pos = vector.round(old_pos)
	local pf_dir = vector.new(old_dir)

	for i = 1, 3 do
		if vector.equals(pf_pos, pos) then
			-- Success! Cart moved on correctly
			return true
		end
		pf_dir, pf_switch = carts:get_rail_direction(
			pf_pos, pf_dir, ctrl, pf_switch, railtype)

		pf_dir, pf_switch = carts:get_rail_direction(pf_pos, pf_dir, ctrl, pf_switch, railtype)
		if vector.equals(pf_dir, {x=0, y=0, z=0}) then
			-- No way forwards
			return false
		end

		pf_pos = vector.add(pf_pos, pf_dir)

		if vector.equals(pf_pos, pos) then
			-- Success! Cart moved on correctly
			return true
		end
	end
	-- Cart not found
	return false