Thanks Bill. Wow that’s quite a difference between the two techniques! I know such volume calculations are just an estimate but it would be a lovely feature to have in Therion!
Sent from my iPhone > On 29 Jan 2022, at 11:41, Bill Gee <[email protected]> wrote: > > Hi Ben - > > The data file I refer to is a Compass file containing centerline and LRUD > data from the cave. It is not from either Therion or Survex. > > In this case the cave is very small, only 50 meters, and there are only 14 > survey stations. Retyping it into a Compass data file did not take long. > > Compass and MeshLab do very different calculations to come up with volume. > For my cave Compass gives about 2900 cubic feet and MeshLab gives over 20,000 > cubic feet (about 585 cubic meters). Compass is doing a simple calculation > based on polygons and using only centerline plus LRUD. MeshLab is a much > more complex calculation based on a 3D model of triangles. Ultimately its > calculation can be traces back to centerline, LRUD, walls, passage height > objects and cross sections. Therion uses all of that to build a .lox file > which, through translations, becomes the MeshLab file. > > ======== > Bill Gee > > >> On Saturday, January 29, 2022 3:42:33 AM CST Ben Cooper wrote: >> Hi Bill, Torsten, >> What is that file; is it a standard output file from Therion or Survex? >> Best regards >> Ben >> >> Sent from my iPhone >> >>>> On 28 Jan 2022, at 12:57, Bill Gee <[email protected]> wrote: >>> >>> Ha! Torsten, you are a magician. Thanks! >>> >>> That was indeed exactly how I calculated this. I had completely forgotten >>> about it. Fortunately the data file still exists on my Windows virtual >>> machine, and Compass produces the number I need to defend. I now know how >>> to reproduce the calculation. >>> >>> Breathing a huge sigh of relief ... >>> >>> ======== >>> Bill Gee >>> >>> >>>> On Friday, January 28, 2022 6:40:00 AM CST Torsten Schnitter wrote: >>>> Hi Bill >>>> >>>> May be you are looking for this ... !? >>>> >>>> cheers, >>>> Torsten >>>> >>>>> ---------- Ursprüngliche Nachricht ---------- >>>>> Von: Bill Gee <[email protected]> >>>>> An: [email protected] >>>>> Datum: 14.08.2019 23:38 >>>>> Betreff: Re: [Therion] How to calculate the volume of a cave >>>>> >>>>> >>>>> Update: After poking around a bit, I discovered that Compass will >>>>> calculate cave volume based on centerline and LRUD data. Doing that >>>>> means I have to run a Windows computer (ugh!) and type in the survey data >>>>> twice (double ugh!) Fortunately the cave for which I need this is small. _______________________________________________ Therion mailing list [email protected] https://mailman.speleo.sk/listinfo/therion
