views:

44

answers:

2

Hi, I am working over a small component for a web portal that show polygons over a map, using OpenLayers, Google Maps, and another proprietary source .

The user has the points in PSAD56 (UTM) datum and I need to change it to WGS84 in order to use with Google Maps. I have at hand both Oracle 9i without spatial extensions and postgis. Can Oracle locator or Postgis make this transformation? Or is there an open source that can do that?

A: 

OpenLayers can also transform between coordinate systems and projections using the Proj4JS library. Note this is probably only viable if you have relatively small amounts of data to transform.

winwaed
Thank you. I am really new to this world, how can we obtain the EPSG code for PSAD56 - Bolivia, in order to use proj4js? Or if you can tell me, how I can do that operation with postgis?
ric
SpatialReference.org is usually a good place to look, however I've just looked, and it sounds like PSAD56 is used for multiple countries, Especially Peru.
winwaed
+1  A: 

You could load the user data into Postgis. How you do that depends on which data format they use. shp2pgsql script if the points are available as shapefile.

To transform your geometries into WGS84, you then run

ST_Transform(the_geom,4326)

Bolivia could be either in

  • PSAD56 / UTM zone 19S ... EPSG:24879 or
  • PSAD56 / UTM zone 20S ... EPSG:24880

You'll have to ask your user.

underdark
For further GIS related questions, you might want to ask at gis.stackexchange.com
underdark
yeah! that's what I am looking for. Thank you.
ric