Stacho Mudrak wrote
In any case, soon I will probably add those missing area symbols - blocks, snow, ice and mud, but I am afraid, blocks will not look nice.
But it has to be better than drawing them by hand
One question, what is the difference between mud and clay? clay = mud without water? Should it mean the same, or not?
I am not a sedimentologist, but I think that clay is a type of mud, usually of a finer grain. Mud possibly covers silt and sand as well. As a cave surveyor I do not think that I can tell a difference, so would would not particularly want different symbols, but I suspect there are lot of people out there who do. I have tended to use minus signs for mud and dots for sand. But I most probably should be using dots for all of it Andrew Atkinson
We have a problem with that - in one symbol set used in
Lechuguilla cave
(I am not able to locate it on the WEB now), we have found a RAFT and RAFT CONE symbols. We still do not know, for what we should use them... Therefore we would like to remove them (I guess, nobody used them until now).
I think these are a type of speleothem - calcite raft floating on water. I'mnot sure about a raft cone, but presumably it is some variation. These are certainly quite rare formations....
I am guessing but are raft cones where a 'raft' has calcited around a stal? Andrew Atkinson
+++ Andrew Atkinson [04-12-14 20:10 -0800]:
Stacho Mudrak wrote
In any case, soon I will probably add those missing area symbols - blocks, snow, ice and mud, but I am afraid, blocks will not look nice.
But it has to be better than drawing them by hand
It's easier :-) , but it will look worse :-( We do need to solve this problem somehow. Current rock-drawing is super-slow, but I want my finished rocks to look realistic as well (i.e. not sticking through the walls).
One question, what is the difference between mud and clay? clay = mud without water? Should it mean the same, or not?
I am not a sedimentologist, but I think that clay is a type of mud, usually of a finer grain. Mud possibly covers silt and sand as well. As a cave surveyor I do not think that I can tell a difference, so would would not particularly want different symbols, but I suspect there are lot of people out there who do. I have tended to use minus signs for mud and dots for sand. But I most probably should be using dots for all of it
Do the UIS have different symbols for this? clay is indeed sediment with very fine particles. I think of there being 'dry sediment' (sand symbol) and 'wet sediment' (mud symbol). I think that's plenty for my purposes, but Therion just needs to provide whatever the various symbol sets provide. Wookey -- Aleph One Ltd, Bottisham, CAMBRIDGE, CB5 9BA, UK Tel +44 (0) 1223 811679 work: http://www.aleph1.co.uk/ play: http://www.chaos.org.uk/~wookey/
It's easier :-) , but it will look worse :-(
We do need to solve this problem somehow. Current rock-drawing is super-slow, but I want my finished rocks to look realistic as well (i.e. not sticking through the walls).
MartinS has found a dirty trick how to solve this problem, so now it is just a question of implementation. :) In any case, we would welcome a good example (or even an algorithm), how those random blocks should look like...
Do the UIS have different symbols for this? clay is indeed sediment with very fine particles. I think of there being 'dry sediment' (sand symbol) and 'wet sediment' (mud symbol).
UIS is using dots symbol for "Sand-Silt-Clay-Humus". So I suggest to let exist clay symbol and add mud symbol. Then we will have three symbols: mud for wet sediment, clay and sand for dry sediment. In UIS symbol set, it will be the same symbol.
I think that's plenty for my purposes, but Therion just needs to provide whatever the various symbol sets provide.
We have a problem with that - in one symbol set used in Lechuguilla cave (I am not able to locate it on the WEB now), we have found a RAFT and RAFT CONE symbols. We still do not know, for what we should use them... Therefore we would like to remove them (I guess, nobody used them until now). And we would also like to add three new point symbols we are missing: stalactites stalagmites stalactites-and-stalagmites They will mark places, where these speleothems occur in bigger amounts. Regards, S.
+++ Stacho Mudrak [04-12-16 10:07 +0100]:
It's easier :-) , but it will look worse :-(
We do need to solve this problem somehow. Current rock-drawing is super-slow, but I want my finished rocks to look realistic as well (i.e. not sticking through the walls).
MartinS has found a dirty trick how to solve this problem, so now it is just a question of implementation. :) In any case, we would welcome a good example (or even an algorithm), how those random blocks should look like...
Take a look at the tunnel code. That is a nice implementation. I think there have actually been two. The original one let you draw a 'gradient line' across an area which indicated that rocks should get smaller in the direction of the line, and there were several sizes of rocks. Then rocks were drawn so that small rocks would stay on top of large rocks if they fitted on top. Something like that anyway. One problem with this was that is was very slow to render, so I think current tunnel has a slightly different scheme - anyone on this list moreuptodate than me? I see from Martin Sluka's example that therion already does neat clipping of rocks on top of each other which is good (I have carefully been drawing them non-overlapping, as I hadnt realised this would work.) The important thing is to be able to get quite a 'natural' look, with randomised sizes, but still the ability to say at least 'theserocks are mostly big/medium/small'.
We have a problem with that - in one symbol set used in Lechuguilla cave (I am not able to locate it on the WEB now), we have found a RAFT and RAFT CONE symbols. We still do not know, for what we should use them... Therefore we would like to remove them (I guess, nobody used them until now).
I think these are a type of speleothem - calcite raft floating on water. I'mnot sure about a raft cone, but presumably it is some variation. These are certainly quite rare formations.... Wookey -- Aleph One Ltd, Bottisham, CAMBRIDGE, CB5 9BA, UK Tel +44 (0) 1223 811679 work: http://www.aleph1.co.uk/ play: http://www.chaos.org.uk/~wookey/
At 11:53 +0000 16.12.2004, Wookey wrote: *******************************************
I think these are a type of speleothem - calcite raft floating on water. I'mnot sure about a raft cone, but presumably it is some variation. These are certainly quite rare formations....
Typical for Lechuguia cave and simillar karst I think. There is an important difference od mud/clay and sand in sense of sedimentation - the sand sedimented in flowing water but mud/clay in static water, so there should be two different symbols probably. Martin (S) --
martinsluka@mac.com said:
There is an important difference od mud/clay and sand in sense of sedimentation - the sand sedimented in flowing water but mud/clay in static water, so there should be two different symbols probably.
I think there are indeed two different symbols for sand and clay in most symbol sets. We usually use dots for sands (as in UIS), and dashes for clay. Eric. -- -- ^v^ ^v^ ^v^ ------------------------------------------------------------------- Eric Madelaine tel: (+33) 4 92387807 (secr: 7556, fax: 7765) INRIA Sophia-Antipolis email: Eric.Madelaine@sophia.inria.fr BP 93 06902 Sophia-Antipolis CEDEX FRANCE ------------------------------------------------------------------- SIS (Section INRIA Speleo): http://www.inria.fr/agos-sophia/sis SophiTaupes (Section Speleo du COV): http://www-sop.inria.fr/agos-sophia/sis/COV/ST.html CDS 06: http://www.ffspeleo.fr/cds/06/
I am guessing but are raft cones where a 'raft' has calcited around a stal?
No idea. But I think it's better to remove them, before somebody will use this symbol for something wrong. It will be no problem to add later, when it will be clear what they mean. Regards, S.
On Dec 16 2004, Wookey wrote:
+++ Stacho Mudrak [04-12-16 10:07 +0100]:
It's easier :-) , but it will look worse :-(
We do need to solve this problem somehow. Current rock-drawing is > > super-slow, but I want my finished rocks to look realistic as well > > (i.e. not sticking through the walls). MartinS has found a dirty trick how to solve this problem, so now it > is just a question of implementation. :) In any case, we would welcome > a good example (or even an algorithm), how those random blocks should > look like...
Take a look at the tunnel code. That is a nice implementation. I think there have actually been two. The original one let you draw a 'gradient line' across an area which indicated that rocks should get smaller in the direction of the line, and there were several sizes of rocks. Then rocks were drawn so that small rocks would stay on top of large rocks if they fitted on top. Something like that anyway. One problem with this was that is was very slow to render, so I think current tunnel has a slightly different scheme - anyone on this list moreuptodate than me?
I have been using tunnel to draw up caves. The rock and sand symbols will be recoded again in a little while. I believe the current implimentation, randomly puts down symbols, and checks if they are in the area and if they overlap any other symbol already there. The symbols themselves have clear outlines around them. As these outlines can not overlap, the symbols will not get too close to each other. User options tell tunnel wheather to allow bolders to randomly rotate the bolders, and by how much to randomly scale them. Ordering is important, although not well implimented, so that more important symbols such as slopes are put down before bolders. I believe futher optimisation is planned by creating a bitmap that records free areas. So to choose where to put down the sybol, it can be checked against a bitmap to see if it will fit there, before clipping the different shapes together, which is more computationaly expensive. To get nice looking bolders, it is worth drawing a few different shapes, so typically I use a quadraleral bolder and a triangular bolder. Ideally which bolder is placed should be done randomly. But at the moment all the quadralerals are placed first, and then the triangles are placed. Tunnel can be found at http://www.goatchurch.org.uk/tunnelx/ I suspect that the executable provided is out of date, so you are better of downloading the source from cvs and compiling it yourself. Examples of output are at: http://cucc.survex.com/expo/smkridge/204/surveys/plan2004.png I believe Wookey may also be refering to a pull back feature, where by somehow sybmols can be pulled back to a line. I do not use this, but understand it iis to do with trying to make walls of boulders, or sticking stals into ceilings. Cheers, Martin
Andrew Atkinson wrote:
I think these are a type of speleothem - calcite raft floating on water. I'mnot sure about a raft cone, but presumably it is some variation. These are certainly quite rare formations....
I am guessing but are raft cones where a 'raft' has calcited around a stal?
A raft is as you thought, calcite rafts floating on water. When these are disturbed the calcite rafts sink and can build up on the bottom of the pool as 'conical' shaped piles. The pool can dry up and the raft cones will be left. Thus they are different to rafts and so have a different symbol. Yes they are not common but they are not rare. Mike -- Mike Lake Caver, Linux enthusiast and interested in anything technical.
participants (7)
-
Andrew Atkinson -
Eric Madelaine -
M.J. Green -
Martin Sluka -
Michael Lake -
Stacho Mudrak -
Wookey