RTOPO Hydrology CAD for topography, Editing XYZ point files

Simple, powerful and inexpensive CAD software for surveying. You can do triangulation, isolines, color-filled contour maps, sections, intersections, volume, editing XYZ files, simulation of rainwater runoff (see https://rumble.com/v3tosh4-rtopo-hydrology-simulating-rainwater-runoff.html) and much more. You can represent 4D points cloud and process hundreds of thousands of points or triangles, even on less powerful PCs.
You can see how to modify a XYZ point file. RTOPO can edit interactively the points (modify, delete or add), can modify the coordinates, the code and the position (in 3DPOLY or SPLINE).
http://rcad.eu/rtopo/
Watch the subtitles for better understanding.