asheshouse at btinternet.com
Sun Nov 20 10:13:26 GMT 2005
Just a couple of thoughts arising from my tinkering with Daren data.
Two additional data styles would probably cover all eventualities.
"pitch" with three variables defined lx, ly, angle
those being long axis dimension, short axis dimension and bearing of
This would be like "passage" but would give a correctly modelled
"chamber" three variables left, up, down
a series of points in a loop arranged clockwise.
If the chamber was surveyed as radials from a central point then this
could still be modelled using "chamber" but entering the data as two loops.
modelling of sharp corners may need some thought?
I've noticed other comments about the 3D model looking better if
modelled as oval tubes rather than prisms. This would not necessarily be
more accurate. Due to lack of detail data the 3D model is likely to
always just be a representation rather than an accurate model. Compass
gives three options, tubes, octagonal prisms, rectangular prisms. Which
looks best depends on the form of the original cave. I would think it
would be most useful to develop a fully featured solid modelling system
based on a simple rect. prism. Once all the visualisation bugs are
resolved in the rectangular form it _may be_ relatively simple to
convert it to other cross section types.
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