Hi Frank - Thanks very much for your continued help. I'm still only a the learning stage, and so am just having a play trying to get a working system going.
For testing purposes, the shapefile file I'm using is here: http://www.cdc.gov/epiinfo/shape/Cntry00.zip What I'd like to do is load this shape file in to a PostGIS database, then have mapserver render it projected as mercator (WGS84?), overlayed with points I've got in another table (specified as Lat/Long). As you can probably tell, most of my lack of understanding revolves around projections - Are there any good resources you could point me towards regarding this? Kind Regards, Neil. On 2/7/06, Frank Warmerdam <[EMAIL PROTECTED]> wrote: > On 2/7/06, Neil Saunders <[EMAIL PROTECTED]> wrote: > > Hi All! > > > > Frank; Thanks for that tip, now I'm setting the projection on the layer and > > mapserver is doing my translation into merc which is great. However, the > > units its projecting it into are meters. If I set, as I have, the units > > in the layer projection to be m and the units of the map to be dd then i > > get a "[MapServer Error]: msProcessProjection(): unknown unit conversion > > id" error. > > Neil, > > If your map is going to be in mercator you are going to > have to specify your extents in some linear measure (like > meters), not in lat/long. > > > So I tried to convert my data into a new shapefile so i could re-import > > it, using the following command: > > ogr2ogr -s_srs "+proj=latlong" -t_srs "+proj > > =merc +ellps=WGS84" e:\upload\worldmerc.shp e:\upload\cntry.shp > > ERROR 1: Failed to find required field in datum.csv in > > InitDatumMappingTable(), > > using default table setup. > > Failed to transform feature 180. > > ERROR 1: Terminating translation prematurely after failed > > translation of layer cntry00 > > I'm not exactly sure why you get this error. But you really > should be specific about datum. > > eg. > ogr2ogr -s_srs "+proj=latlong +datum=WGS84" -t_srs "+proj=merc > +datum=WGS84" e:\upload\worldmerc.shp e:\upload\cntry.shp > > I would add it really frightens me when you leave > so many mercator parameters defaulted. > > Best regards, > -- > ---------------------------------------+-------------------------------------- > I set the clouds in motion - turn up | Frank Warmerdam, [EMAIL PROTECTED] > light and sound - activate the windows | http://pobox.com/~warmerdam > and watch the world go round - Rush | Geospatial Programmer for Rent >
