Re: [Flightgear-devel] A question regarding accurate taxiways
Arnt Karlsen wrote: ..IMHO, the wise thing to do is extend Robin's database format to do our thing the way we wanna do it, and use that to win him over our way exporting to his format, and ship him both. Robin's user's corrections remains useful to us, even if they stick with their current format. After thinking this through a bit I do agree. By adding a new taxiway tag (the most important right now, there are some runway issues I want to see resolved at a later stage) you could prefer the new way over the old way if both are present. Since David Luff mentioned that most X-Plane users are using taxidraw these days we have a huge advantage now ... Erik ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-devel] A question regarding accurate taxiways
Martin Spott wrote: On the other hand it might be worthwhile to spend this effort once we have a means to reliably convert airport layouts back and forth between vector layout and X-Plane format. To my opinion the X-Plane format isn't qualified for accurate runway and taxiway layout. It's way too course by using the centerlines only approach. I'd much rather see a polygon (or even quad) based approach. Erik ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-devel] A question regarding accurate taxiways
Martin Spott wrote: Erik Hofman wrote: To my opinion the X-Plane format isn't qualified for accurate runway and taxiway layout. This is Harald's opinion as well as mine ! _But_: Our opinion on this format actually does not change it. Right ? And as long as FG sticks to rely on this X-Plane data it makes little sense to generate airports in a different format - as long as we are unable to convert back and forth. For example it would be a nice feature to automagically create outlines and a centerline from X-Plane data and create a set of overrides from FAA/SIA/whoever data. I can see two kind of airports in the Robin database : - those with detailed taxiways and apron : they have no more any taxiway description because the mass of little pseudo-apron used to make details and curves have replaced the one or two default taxiways ; - those without detaild taxiways; they have one or two taxiways paralel to the runways. So I have the feeling that we can not extract any meaningfull information from the runways data from this database, the side effect is that there is no need to convert from one format to another hypothetical format. Probably we are going to merge this data into a single set of airport descriptions in vector format for FlightGear. What are we going to do if something is being changed in Robin's database ? Are we going to maintain a parallel database ? Regards, Martin. We have 20.000+ airports in Robin base, we want to change 50 or 500 of them. I think we should keep Robin's database and use it as we use it today, and use a new database for the few airports we want to upgrade with a new format. Durk Taslma is using a network to describe the ground traffic pattern, we are no more talking about polygons. Harald. ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-devel] A question regarding accurate taxiways
On Fri, 14 Oct 2005 18:54:47 +0200, Harald wrote in message [EMAIL PROTECTED]: Martin Spott wrote: Erik Hofman wrote: To my opinion the X-Plane format isn't qualified for accurate runway and taxiway layout. This is Harald's opinion as well as mine ! _But_: Our opinion on this format actually does not change it. Right ? And as long as FG sticks to rely on this X-Plane data it makes little sense to generate airports in a different format - as long as we are unable to convert back and forth. For example it would be a nice feature to automagically create outlines and a centerline from X-Plane data and create a set of overrides from FAA/SIA/whoever data. I can see two kind of airports in the Robin database : - those with detailed taxiways and apron : they have no more any taxiway description because the mass of little pseudo-apron used to make details and curves have replaced the one or two default taxiways ; - those without detaild taxiways; they have one or two taxiways paralel to the runways. So I have the feeling that we can not extract any meaningfull information from the runways data from this database, the side effect is that there is no need to convert from one format to another hypothetical format. Probably we are going to merge this data into a single set of airport descriptions in vector format for FlightGear. What are we going to do if something is being changed in Robin's database ? Are we going to maintain a parallel database ? We have 20.000+ airports in Robin base, we want to change 50 or 500 of them. I think we should keep Robin's database and use it as we use it today, and use a new database for the few airports we want to upgrade with a new format. Durk Taslma is using a network to describe the ground traffic pattern, we are no more talking about polygons. ..IMHO, the wise thing to do is extend Robin's database format to do our thing the way we wanna do it, and use that to win him over our way exporting to his format, and ship him both. Robin's user's corrections remains useful to us, even if they stick with their current format. ..and, we can reel them in pretty nicely our way setting up a web site taxi way editor app for user input of their database corrections, to output the corrected data on the spot, and in both formats. -- ..med vennlig hilsen = with Kind Regards from Arnt... ;o) ...with a number of polar bear hunters in his ancestry... Scenarios always come in sets of three: best case, worst case, and just in case. ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-devel] A question regarding accurate taxiways information
On October 11, 2005 09:42 am, Vassilii Khachaturov wrote: 1) by some kind of image processing following the Ghostview output. Of course, since the internal graphics is vector, it might be possible to infer more from various rendered resolutions. 2) Other approach would be to reverse engineer the original PS, if any, from the PDF --- I'm afraid it's not very gratifying... Why would there be needs of reverse engineering? The purpose of reading the PDF file is only to extract the taxiways' outline. 3) Yet another approach would be to ask the FAA for the data source feed --- after all, this is U.S. government work that is in public domain. And, of course, this is only a US-related solution... I have seen airport diagrams in PDF format for airports in countries other than the US. For example: http://www.sia.aviation-civile.gouv.fr/aip/enligne/metropole/aip/VAC/T/VAC AD 2.LFBO.pdf Ampere ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-devel] A question regarding accurate taxiways
Ampere K. Hardraade wrote: I have seen airport diagrams in PDF format for airports in countries other than the US. For example: http://www.sia.aviation-civile.gouv.fr/[...] This is correct, the French approach is very progressive, as is the Danish (http://www.slv.dk/Dokumenter/dscgi/ds.py/View/Collection-618), but we have to face the fact that most countries don't offer this service. Anyway nobody prevents you to convert these charts and load the resulting bitmaps into TaxiDraw as a background image. It is no problem at all to convert a PDF into any other vector format but I've found it very difficult to define charcteristics that automagically can tell between runways, taxiways and other objects that happen to be part of the chart. You always have to spend significant manual effort to separate the data we need. On the other hand it might be worthwhile to spend this effort once we have a means to reliably convert airport layouts back and forth between vector layout and X-Plane format. Cheers, Martin. -- Unix _IS_ user friendly - it's just selective about who its friends are ! -- ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-devel] A question regarding accurate taxiways
Martin Spott wrote: ... It is no problem at all to convert a PDF into any other vector format but I've found it very difficult to define charcteristics that automagically can tell between runways, taxiways and other objects that happen to be part of the chart. You always have to spend significant manual effort to separate the data we need. On the other hand it might be worthwhile to spend this effort once we have a means to reliably convert airport layouts back and forth between vector layout and X-Plane format. Cheers, Martin. Except that the X-Plane format is just a bad hack todays and has reach its limitation. This file format does not handle taxiways or curves, or ground traffic or docking systems or usual airport buildings. It's just a soup of rectangles (except of course the runways and frequency informations). Harald. ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-devel] A question regarding accurate taxiways
Harald JOHNSEN wrote: Except that the X-Plane format is just a bad hack todays and has reach its limitation. [...] I know the file format very well as I've done lots of manual changes with my favourite text editor - but what are you aiming at ? Martin. -- Unix _IS_ user friendly - it's just selective about who its friends are ! -- ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-devel] A question regarding accurate taxiways information
Since FAA has airport diagrams in PDF format, would it be possible to extract taxiways information BTW, the tower and the beacon, if any, can also be extracted from it, as well as the windsocks, ILS hold lines etc. directly from a PDF file such as this http://204.108.4.16/d-tpp/0510/00375AD.PDF to produce taxiways usable in FlightGear? 1) by some kind of image processing following the Ghostview output. Of course, since the internal graphics is vector, it might be possible to infer more from various rendered resolutions. 2) Other approach would be to reverse engineer the original PS, if any, from the PDF --- I'm afraid it's not very gratifying... 3) Yet another approach would be to ask the FAA for the data source feed --- after all, this is U.S. government work that is in public domain. And, of course, this is only a US-related solution... Vassilii ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
