Hi Xander, Victor & All,
Folks, I think I have good news! The solution seems to be: surface TINs+Area polygon>Extrude Between>Interpolate Polygon to Multipatch>Enclose Multipatch>Is closed 3D>Inside 3D AND 3D points!! I guess the latter should have been obvious from the start, but I didn't realize it until later on and I didn't repeat the Inside 3D step until just now. That´s why I told Xander that it didn'y work either, sorry about that, a clear case of beginner mistake!
So, it was really both your answers that put me in the right path, thanks a lot guys! I still have to double check the results and still have to deal with some outliers, but this time it's XY, not Z, outliers, and certainly caused by the need to edit my surface TINs to ensure total area coverage, this should take care of all outliers.
OK, it's not the ideal solution, it would be better if I could get a selection directly on my finds/points feature class. With Inside 3D what you get is a table, so next I have to join both tables and then "display XY data" to check the results, but it seems to be A solution - in other words, that's one small step for the GIS Community, one giant leap for Armando...
As I've been trying and experimenting a lot, my map and scene documents are full of "noise", so what I'll do is improve my input data and start fresh on new documents, making sure that I write down every step so that I can post the whole sequence+results+issues in case someone else finds it useful.
Xander, thanks a lot for your offer, I really appreciate that! I could send you the following, for a small experiment:
- the topographic data pertaining to the upper and lower boundaries of a particular archaeological unit (XYZ points), as a feature class and/or an excell table
- the corresponding top and bottom surface TINs
- an excavation area polygon (2D)
- a sample finds feature class (XYZ points; again, feature class and/or table), possibly including finds that definitely belong to that archaeological unit and others that definitely don't, to see if the selection method (whichever) only selects the former?
These would be "raw data", from ArcMap. If you prefer, I could send the extruded polygon and 3D finds feature class as well or instead. Please let me know if this would be enough or you need something else/more/different. Cheers!