Re: [Flightgear-devel] How to convert from WGS84 coordinates?
I've found Geotrans Translator v.2.2.5 software; I tried using it for converting from WGS84/NUTM33 to WGS84/Geodetic coordinates and I had some not very good results. I don't know if I am making something wrong with that software or the starting coordinates are not accurate (although they should be :-) I'll investigate more and download GDAL too. Let's see. Do you know Geotrans too? Is it of any value? If this is the NIMA Geotans tool, it is an excellent tool. Norman Yes it is. But I'm not very happy with that. Maybe it's just me (I'm totally new to those coordinates systems) or the fgfs scenery are not accurate enough. Anyway the first results are not very satisfying. Objects placed into fgfs scenery, using the coordinates which Geotrans converted for me, are in the wrong place. Maybe I'm missing something. Are experienced with that Geotrans? May I send you some test files and double check with you what I am doing so to be shure it's not me doing it wrong? Thx in advance, Roberto ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-devel] How to convert from WGS84 coordinates?
Quoting Robicd : Datum: WGS84 Projection: NUTM33 Coordinate top left x: 353620.2 y: 4225543.6 Coordinate bottom right x: 354212.2 y: 4225976.1 These are UTM North Zone 33 I entered these coordinates in fgsd and I had my test picture mirrored upside down. It appears that your bottom has a northings (y) value greater than your top. Anyway, I get these ( decimal ) values : x: 353620.2 y: 4225543.6 = lat: 38.16592 lon: 13.32904 x: 354212.2 y: 4225976.1 = lat: 38.16991 lon: 13.33570 HTH -Fred ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-devel] How to convert from WGS84 coordinates?
Hi Fred, Datum: WGS84 Projection: NUTM33 Coordinate top left x: 353620.2 y: 4225543.6 Coordinate bottom right x: 354212.2 y: 4225976.1 These are UTM North Zone 33 I entered these coordinates in fgsd and I had my test picture mirrored upside down. It appears that your bottom has a northings (y) value greater than your top. Anyway, I get these ( decimal ) values : x: 353620.2 y: 4225543.6 = lat: 38.16592 lon: 13.32904 x: 354212.2 y: 4225976.1 = lat: 38.16991 lon: 13.33570 You're totally right. That can't be. Bottom right coordinate is wrong of course. I checked again (not the same image, but from the same source, which is www.atlanteitaliano.it, and at almost same coordinates) and I got what follows: Top Left x: 353582.4 y: 4225544.6 Bottom right x: 354210.8 y: 4225048.5 Anyway, can you please explain to me how to place some aerial/pictures into a scene in order to texture the terrain? I'd like to use those pictures from www.atlanteitaliano.it but I don't find any docs about this procedure. I know it's possible, there are screenshots at www.flightgear.org, but there's no documentation. Thx, Roberto -- Sparen beginnt mit GMX DSL: http://www.gmx.net/de/go/dsl ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-devel] How to convert from WGS84 coordinates?
Datum: WGS84 Projection: NUTM33 Coordinate top left x: 353620.2 y: 4225543.6 Coordinate bottom right x: 354212.2 y: 4225976.1 These are UTM North Zone 33 http://www.dmap.co.uk/utmworld.htm You probably will want to warp these into LatLon space http://www.remotesensing.org/gdal/gdal_utilities.html#gdalwarp I've found Geotrans Translator v.2.2.5 software; I tried using it for converting from WGS84/NUTM33 to WGS84/Geodetic coordinates and I had some not very good results. I don't know if I am making something wrong with that software or the starting coordinates are not accurate (although they should be :-) I'll investigate more and download GDAL too. Let's see. Do you know Geotrans too? Is it of any value? Roberto ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
RE: [Flightgear-devel] How to convert from WGS84 coordinates?
Robicd writes: I've found Geotrans Translator v.2.2.5 software; I tried using it for converting from WGS84/NUTM33 to WGS84/Geodetic coordinates and I had some not very good results. I don't know if I am making something wrong with that software or the starting coordinates are not accurate (although they should be :-) I'll investigate more and download GDAL too. Let's see. Do you know Geotrans too? Is it of any value? If this is the NIMA Geotans tool, it is an excellent tool. Norman ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-devel] How to convert from WGS84 coordinates?
Manuel Massing ha scritto: Hello Robicd, I've made a .ase 3d object (a Villa of my town) for a scenery. I have a satellite picture of the place where the Villa resides, which has datum wgs84 coordinates of the two corners of the bitmap. I really don't know how to convert such coordinates (1st corner is 353620.2/4225543.6, 2nd corner is 354212.2/4225976.1) to a format suitable for a .stg file. These coordinates don't mean much by themselves, you need to know which projection they relate to. Probably a UTM projection in your case. You're right, the picture shows a Projection field too. Complete infos are: Datum: WGS84 Projection: NUTM33 Coordinate top left x: 353620.2 y: 4225543.6 Coordinate bottom right x: 354212.2 y: 4225976.1 Scale: 1:2944 Is this enough for making a correct unit conversion? I would like to comprehend what all those units mean but ... I guess there's no Coordinates-MiniHowto :-( There should be one. I would recommend you install gdal (http://www.gdal.org/), and use gdalinfo to get projection information for your file. You can than use gdal_translate + gdalinfo or a proj4 tool to convert between projected or pixel coordinates and lat/lon. I'll take a look. cheers, Manuel The Agriculture Department of the State I lieve in (which is Italy) offers for free those aerial/satellite pictures which are not the same quality as the Keyhole's ones but are pretty good anyway. The whole state is covered, resolution is not very high but there are rumours about near future enhancements of the content. I think I can't redistribute those images being non GPLd but they're free for personal use and they look very nice :-) I promise, I will write down a howto as soon as I get them texturizing my landscape in FGFS :-) Thx, Roberto ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-devel] How to convert from WGS84 coordinates?
You're right, the picture shows a Projection field too. Complete infos are: Datum: WGS84 Projection: NUTM33 Coordinate top left x: 353620.2 y: 4225543.6 Coordinate bottom right x: 354212.2 y: 4225976.1 Those are odd looking numbers. The WGS84 standard specifies a datum, which is a mapping of lat/lon/altitude coordinates to a 3D cartisian coordinate system. Specifically, it calls the zero-altitude surface (sea level, sorta, although it doesn't always coincide with actual MSL in all areas) a slightly flattened ellipsoid with an exactly specified equation. That said, WGS84 numbers are still plain looking latitude and longitude values, usually written in degrees. They aren't ever called x or y (which for obvious reasons is really confusing). My guess is that those numbers are arbitrary 2D coordinates used by the satellite photo software. Or maybe they're well-specified 2D coordinates in the NUTM33 projection* about which I know nothing. * A projection is not the same thing as a datum. It is a mapping of 2D (!) lat/lon values to a 2D cartesian surface. Becuase this transformation is lossy, projections get really, really complicated. Many are specified with giant lookup tables and/or curve fitting. I'd hunt around in the documentation you have for the photo to try to figure out what it's talking about. Andy ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
RE: [Flightgear-devel] How to convert from WGS84 coordinates?
Andy Ross writes: You're right, the picture shows a Projection field too. Complete infos are: Datum: WGS84 Projection: NUTM33 Coordinate top left x: 353620.2 y: 4225543.6 Coordinate bottom right x: 354212.2 y: 4225976.1 Those are odd looking numbers. These are UTM North Zone 33 http://www.dmap.co.uk/utmworld.htm You probably will want to warp these into LatLon space http://www.remotesensing.org/gdal/gdal_utilities.html#gdalwarp is a quality tool for doing this, there are others HTH Norman ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-devel] How to convert from WGS84 coordinates?
Hello Robicd, I've made a .ase 3d object (a Villa of my town) for a scenery. I have a satellite picture of the place where the Villa resides, which has datum wgs84 coordinates of the two corners of the bitmap. I really don't know how to convert such coordinates (1st corner is 353620.2/4225543.6, 2nd corner is 354212.2/4225976.1) to a format suitable for a .stg file. These coordinates don't mean much by themselves, you need to know which projection they relate to. Probably a UTM projection in your case. I would recommend you install gdal (http://www.gdal.org/), and use gdalinfo to get projection information for your file. You can than use gdal_translate + gdalinfo or a proj4 tool to convert between projected or pixel coordinates and lat/lon. cheers, Manuel ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-devel] How to convert from WGS84 coordinates?
Robicd wrote: Hi, I've made a .ase 3d object (a Villa of my town) for a scenery. I have a satellite picture of the place where the Villa resides, which has datum wgs84 coordinates of the two corners of the bitmap. I really don't know how to convert such coordinates (1st corner is 353620.2/4225543.6, 2nd corner is 354212.2/4225976.1) to a format suitable for a .stg file. Where should I look at for docs? The online ones where not very clear to me :-( Any help? fgsd can help you for that task. http://fgsd.sf.net -Fred ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-devel] How to convert from WGS84 coordinates?
Where should I look at for docs? The online ones where not very clear to me :-( Any help? fgsd can help you for that task. http://fgsd.sf.net Not very much since fgsd does not work very good under Win98, it crashes and I can't get him working with aerial pictures :-( still hungry for hints, Roberto ___ Flightgear-devel mailing list Flightgear-devel@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
