…so to clarify further …
As the gradient of a survey shot
increases, therion switches from the assumption that passages are measured LRUD
(vertical up down) to an assumption that they are measured LR-front-back (up
down perpendicular to the passage orientation) and then at +-90 deg to the
assumption that they are measured NSEW.
You can control the inclination at which
the first change occurs by adding
vthreshold 40 degrees
to your centerline block of data.
Unfortunately we cannot change the NSEW
behaviour (yet).
What you need to know of course, is approach
the surveyors took when they were collecting the data, and adjust your input
accordinly.
Bruce
From:
therion-bounces@speleo.sk [mailto:therion-bounces@speleo.sk] On Behalf Of Bruce
Sent: Thursday, 1 November 2012
7:08 a.m.
To: '
Subject: Re: [Therion] Doubt about
vertical sections
Marco
I tested your example and got the result
you described with both xvi and pdf outputs.
I think you have found the transition
defined by ‘vthreshold’.
From the Therion Book…
“
vthreshold <number> <units> ◃ threshold for interpreting LRUD readings as left-right-front-back
reading perpendicular to the shot.
If passeges are horizontal (inclination
< vthreshold), LR is perpendicular to the shot and UD is vertical.
If passages are more or less vertical
(inclination > vthreshold), even UD becomes perpendicular to the shot –
otherwise passages would not look very good. In the case of vertical shots, UD
is interpreted as north-south dimension from the station to allow tube-like
modelling of verticals
“
I had thought the default value of
vthreshold was 60 degrees, but it seems it may be around 67.5 degrees.
Bruce