April 2019 - Therion

Re: [Therion] Point altitude/deph, Help !
by Xavier Robert 28 Jun '22

28 Jun '22

Hi all, I think I have found a trick. The other Xavier led me to the right tracks, thanks a lot ! Finally, this is quite simple with the point altitude, and no need to change anything inside the : - If we use the point altitude only with the option -align, we get the altitude - If we use the point altitude with the options -align and -value [-1004 m] where 1004 is the altitude of the main entrance, we print the depth only for that point (Do not forget the " - " before the altitude of the main entrance), and thus, we do not erase the classic point altitude. The only (small) limits are : * If the main entrance changes, we need to manually update ALL the points that print the depth. But that should not be be everyday, and not a big issue to do that. * the symbology of the two points is the same. I will have a look for a way to modify that and let you know if I find a trick (If I copy the code of the point Altitude, and call it p_u_depth(expr pos, R, S, A), it crashes...). Cheers, Xav

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"\legendbox" "\loadpicture" and absolute paths
by rowena 14 Mar '21

14 Mar '21

Hello, I am using the "\loadpicture" capability in "\legendbox" constructs to include map sections, elevations, etc. It all works nicely on my PC where I am using relative paths to the pdf files. My club has a desire to archive the map data for posterity - ie if my pc dies or I go walkabout, the map data should still be available so that others can add to the maps as they are extended. I would prefer to have the images included using relative pathnames, rather than absolute pathnames, so that future explorers can download the map data and extend it, without having to duplicate my file hierarchy. How can I include relative paths in the \loadpicture functionality? Thanks, Rowena

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extend
by Marco Corvi 02 Jun '20

02 Jun '20

i think that extend should take values in the interval [-1,1], ie also fractional values, plus some special value such as "ignore" to open loops, and "undefined" to let the program choose, because it's a nuisance to enter a decimal number for every shot (legs + splays). therion uses the left/right normal/reverse etc. solution, and users should be allowed to set extend also for splays, if they need to. for now, let's use left/right/vert, and ignore only to open loops btw, are vertical extend considered in the computation of the cave length by therion ? marco

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World Magnetic Model
by kevin dixon 28 Feb '20

28 Feb '20

The last Therion release 5.4.3 is dated 01 Feb 2019. There has in recent years been a significant change of the Magnetic North Pole location, less so for the Geomagnetic South Pole: https://ngdc.noaa.gov/geomag/GeomagneticPoles.shtml Given the above, an out of cycle World Geomagnetic Model WMM2015v2 was released 04 Feb 2019. When will this update appear in Survex and Therion ? Thanks, Kevin Dixon

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Re: [Therion] Therion 5.4.2. potential bug
by Martin Budaj 31 Jul '19

31 Jul '19

On Sat, Jan 12, 2019 at 10:51 AM Michael <knollesimage(a)t-online.de> wrote: > I have now attached a minimal cave sample produced with 5.4.1. and one > produced with 5.4.2. to demonstrate the displacement. > Hi, the problem is that EPSG:31467 projection uses the "potsdam" datum and the PROJ library used by Therion changed the way how to transform potsdam datum to the standard WGS84 datum – it switched from a simple string parameter (towgs84) to using external grid file (see https://proj4.org/resource_files.html#transformation-grids for examples). No grid files are currently included in the windows Therion distribution, so the transformation is not correct in 5.4.2. Therion needs to be modified to include and use those files – hopefully soon. Best regards Martin

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Page Size
by Markus Boldt 31 Jul '19

31 Jul '19

Hello, how is it possible to "say" Therion to make a PDF-File with for example a Size of DIN A4 (21 x 29,7 cm)? I have tried Page-setup 21 29.7 20 29 0.1 0.1 cm it doesn`t work I have tried Size 21 29.7 cm It doesn`t, too The command is ignored. Greetings Markus

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TerrainTool
by Graham Mullan 28 Jun '19

28 Jun '19

Mike McCombe's TerrainTool has been fixed and is available again from http://www.ubss.org.uk/terraintool/terraintool.php Download and enjoy. It may not use the latest data but it remains the most straightforward way of adding topographic detail to Therion 3D models. Graham

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Best approach for colouring elevations
by Tarquin Wilton-Jones 01 May '19

01 May '19

Hi folks, With either extended or projected elevations, we end up with a few passages overlapping each other. This is intentional (so displacing some of them is not a desired solution). However, it would be nice to be able to colour them differently, to make it easier to see which parts belong to which passage. Colouring by altitude doesn't help in elevations, because they are all at the same altitude when they are overlapping. "Colour by distance from the viewer" is better. This could be coloured by colouring the individual scraps, but that is messy, and hard to maintain. The desired output would be "colour by break". Meaning; each time there is a "break" in the map, change the fg colour. Does anyone have any tips on how best to colour extended/projected elevations? Is "colour by break" possible in some way? Or do you prefer a different approach? Cheers, Tarquin

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Calculation of LRUD from splays
by Markus Boldt 30 Apr '19

30 Apr '19

Hello, is there a possibility to calculate LRUD-Data from splays? It would be nice, if you have not measured LRUD at the point in the cave, but only splays for drawing. I hope you understand my terrible English J. Greetings Markus

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Re: [Therion] Making projected elevations
by Bruce Mutton 30 Apr '19

30 Apr '19

Hi Tarquin Probably better to create a new post for each topic. Makes for smaller bites and easier to respond to. Basically, there is no conversion of sketches from one projection to another. You have to do the work yourself or accept any distortions that a fudge might incur. Have a search on the mail archive for 'projected elevation'. In essence I think you have come to the right conclusions below. https://www.mail-archive.com/therion@speleo.sk/ Check out https://www.mail-archive.com/therion@speleo.sk/msg06370.html and https://www.mail-archive.com/therion@speleo.sk/msg06368.html I started my Therion life as a projected elevation fan, but now I think extended is the way to go (subject to the proviso that they are way more vexatious for a non-trivial cave). Your description of the cave/mine makes it sound perfect for an extended elevation to me, especially as you already have extended sketches. Multiple projections on the same pdf page can only be achieved using map-image to insert them as images. Or you could post-process with another application (which defeats a key advantage of Therion). You could take your extended sketches and just flag them as projected, accepting that there may be gross distortions. You could forget about the xvi file, and print out a projected centreline (one trip file at a time is my preference), and sketch on that the passage detail, scan it, and import it as a background image in XTherion. Then you trace it with XTherion to produce scraps. Seems odd to take an electronic process, and force a pencil and paper stage to it, but that is my preference if the alternative is to have an xvi with no sketches embedded. Bruce -----Original Message----- From: Therion <therion-bounces(a)speleo.sk> On Behalf Of Tarquin Wilton-Jones via Therion Sent: Thursday, 25 April 2019 09:56 To: therion(a)speleo.sk Cc: Tarquin Wilton-Jones <tarquin.wilton-jones(a)ntlworld.com> Subject: [Therion] Making projected elevations, and using map connectors Hi, Still learning (never stop)... I have looked through the various tutorials, and several examples, but I have not found any information on how to create a projected elevation - all tutorials stop at that point with "TODO: show how to do elevations". The software I am using to survey the caves (DistoX2 + SexyTopo) gives me a plan view and an extended elevation, exported as centreline+xvi. The area I am surveying is mostly linear with passages stacked at various levels above each other. As a result, projected elevation is more useful than extended elevation. I know I have to use "-projection [elevation 265]" on my scraps and maps to make them all work when I try to use: export map -projection [elevation 265] However, I have not been able to find how to get from an extended elevation to a projected elevation. I had hoped for some magic where I just create an extended elevation then ask Therion to warp that extended elevation into a projected elevation, but I have come to the conclusion that I probably have to do this: export map -projection [elevation 265] -output elevation265.xvi Then create a dedicated surveyname_elevation265.th2 file and go over all the survey data and create the required scraps for it, without being able to see the sketches in the XTherion scrap editor. Have I made the right assumption, or is there some clever magic that can happen? Does this mean that in order to create two elevations, one facing 265° and one facing 180°, I actually have to do this all twice, creating each scrap from scratch each time? Imagine I want to have half of the cave on a bearing of 265 and the other half on a bearing of 180 in the same file (because the cave turns a corner half way along) - essentially extending a projected elevation. I could export the data once on a bearing of 265, and once on a bearing of 180, then create appropriate scraps for each half, pretend that the ones on a bearing of 100 are actually on a bearing of 265 by using the -projection options of maps and scraps. But then it would warp them to oblivion when trying to make it fit the centreline. So would I actually have to export two PDFs, one with a map that only covers half of the cave on a bearing of 265, and another that covers the other half of the cave on a bearing of 180, and position the outputs very close together by importing them as images into a third map? (Not as insane as it sounds. It is a mine, with major passages all very linear at different levels, and just one significant passage running at right angles to the other passages.) ... snipped... Tarquin _______________________________________________ Therion mailing list Therion(a)speleo.sk https://mailman.speleo.sk/listinfo/therion

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