Shp2img will accept a shapefile as referenced through a mapfile. The mapfile just tells mapserver how to draw the shapefile (what color, symbol, etc...).
Steve >>> On 7/7/2008 at 4:03 PM, in message <[EMAIL PROTECTED]>, Kjell Are Refsvik <[EMAIL PROTECTED]> wrote: > On 7. juli. 2008, at 19.19, Dane Springmeyer wrote: > >> Hi Kjell, >> ... >> You are not alone. Projected coordinate systems can confuse >> beginners and experts alike. > > :-) > > Well, given my completely newbie status as a GIS/Geodata user, I am > very grateful for your patience, explaining these things to me. > >> My understanding is that you have gps data and you are not sure what >> coordinate system it is in. You ran Matt Perry's script to convert >> the text-based coordinates into a shapefile format, but you still >> need to assign a coordinate system. > > I understand. WGS84 and UTM 32V worked fine for the data from Norway. > >> ... >> First, you only need to assign the projection AFTER you run the >> txt2shp.py script. > > OK. I understand. > >> ... >> Second, I can see now (from your image links) that your data was >> collected in Lebanon, which means that the link I directed you to >> will not provide a reference to the correct UTM zone. >> >> There are two possible UTM zones for Lebanon: UTM 36N or UTM 37N. >> >> WGS 84 / UTM zone 36N >> http://spatialreference.org/ref/epsg/32636/ >> >> WGS 84 / UTM zone 37N >> http://spatialreference.org/ref/epsg/32637/ > > 36N seemed to have done thr trick: > PROJCS["WGS_1984_UTM_Zone_36N",GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHE > ROID["WGS_1984",6378137,298.257223563]],PRIMEM["Greenwich",0],UNIT["Degree",0 > .017453292519943295]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_o > f_origin",0],PARAMETER["central_meridian",33],PARAMETER["scale_factor",0.9996 > ],PARAMETER["false_easting",500000],PARAMETER["false_northing",0],UNIT["Meter > ",1]] >> You can check for yourself by downloading a world borders shapefile > (http://thematicmapping.org/downloads/world_borders.php >> ) and a world UTM zone shapefile > (http://earth-info.nga.mil/GandG/coordsys/gislayers/zips/mgrs6x8.zip >> ), both in the WGS 84/EPSG 4326 coordinate system. >> >> If you have more GPS data from other countries I highly recommend >> getting familiar with UTM zones. > > No. Only have data from Norway and Lebanon so far, but looking more > closely into UTM seems like a good idea, especially in order to to get > to grips with paper maps. > > http://www.ia-stud.hiof.no/~kjellare/misc/lebanon_wgs84_UTM36N.png > >> ... >> If you try to load data in different coordinate systems into the >> same QGIS project, QGIS will not (by default) make an effort to >> 'reproject-on-the-fly' when rendering, unless you explicitly set the >> Qgis project to do so. So even if you assign the correct UTM zone to >> your points, if you open them in Qgis along with a base layer in WGS >> 84 projection, they will not line up. You need to go to SETTINGS > >> PROJECT PROPERTIES > PROJECTION > ENABLE ON THE FLY PROJECTION. > > I figured that out, playing around with the Projection settings. > >> Or use the command line program ogr2ogr to reproject your shapefile >> to WGS84/EPSG 4326 from your assumed UTM projection. That command >> would look like: >> >> $ ogr2ogr -s_srs EPSG:32636 -t_srs EPSG:4326 >> lebanon_points_wgs84.shp lebanon_points_utm36N.shp > > Splendid. I will have a go at that. > >> Then, if the assumed source projection was correct, your new >> shapefile should line up with other data in WGS 84. > >> ... >> Yes, they are GUI applications... but don't you just need to >> automate the processing of your GPS data? > > No. In addition to use a unix shell-script to harvest and prepare > geodata from my images using exiftool and some basic text formatting > commands in unix, I also need to prepare the necessary shapefiles and > hopefully find some way of (using shell-scripts) atomatically export > png files to make up the map. > > A quick sketch (using a screengrabbed OpenStreetMap) here: > http://www.ia-stud.hiof.no/~kjellare/misc/programming_goal.png > >> If you want to create one PNG raster then QGIS or uDIG are the ideal >> tools to layout your png map. Just open all your shapefiles (you can >> even merge them all into one shapefile with ogr2ogr), label them, >> then zoom to each group and export a PNG file.... >> >> If you truly want to automate the creation of *many* PNG graphics >> then you'll need to look into scripting a mapping toolkit like >> Mapserver or Mapnik. > > Ouch. I see now that what looked like a way out of this (shp2img) is > not accepting a shapefile as a input. > >> Dane > > Any idea on the complexity in getting the above scripting to work? > > Sincerely, > > Kjell Are Refsvik > Norway _______________________________________________ Discuss mailing list Discuss@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/discuss
