As promised in the previous post, here are further details of the PView User Defined Function (UDF), included in the IP2 spreadsheet, which can be downloaded (including full open source code) from IP2.ZIP.
The PView UDF works by multiplying the 3D coordinates of any set of points by a rotation matrix. The resulting array of 2D coordinates can be plotted in an XY (scatter) chart in the usual way. The function input and output is described in the screen shot below, together with a plot of an example; a simple box structure with a doorway, and a spiral line plotted on one wall.
Part of the output array is shown in the next screen shot. The function output is a single array, which must be entered as an array function.