3D passage wall modeling

[Stacho Mudrak]

Hello,

I've been searching a lot for a software, that could do a realistic 3D 
model of the cave passages, but without success. In fact, only the old 
version of Tunnel supports other types of cross-sections, than rectangles. 
But it requires a huge amount of input data - at least my first experience 
was like that.

Does anybody have any sugestions, where I should continue searching for 
such a software?

Now I have decided to experiment a little bit and do it my self (as part of 
therion project), but I would like to know, whether there has been done 
something in this direction. Do you know any papers, articles or web pages 
to this topic?

Our requirements are following - most of them I believe are very common:

1. the passage walls should be defined by a series of cross sections around 
some centerline

2. centerline should be somehow referenced to survey stations (independant 
of survey shots network)

3. the cross sections should be oriented in any direction and defined by 
shape (standard or user defined) and UDLR dimensions. The existing UDLR 
data must be readable without any other user input.

4. the input should be as minimal, as it can be - it should be able for 
example to read LR dimensions from vectorized plan map (may be also the 
cross section shapes). Or it should be enought to specify, that this 
passage has flat ceiling 2m above station X, and all "up" dimensions would 
be calculated from this information.

5. the output of this algorithm should be triangulation of passage walls.

I would be very thankfull for any other ideas concerning this topic. For 
example, how a cross section orientation can be defined? How to make cross- 
sections morphing - when you have defined only cross section at the 
begining and at the end of passafe, the rest are only UDLR data? How to 
select points on cross-sections, that has to be connected to create a 
correct triangle network?

Greetings, Stacho.