MapThat Admin – Scale Printing using WGS 84 (Long Lat) 4326

Question

Does the MapThat Scale Print tool print OS MasterMap vector geometry which has been projected to WGS 84 – SRID 4326?

Answer

Yes, the MapThat Scale Print tool can print OS MasterMap vector geometry which has a projection of either 27700 (BNG) or 4326 (Long/Lat). You can specify this setting in the MapThat Control Table ‘MT_ADMIN_SETTINGS’, using the DBSRID record and inserting a value of:

27700 -  for British National Grid

Or

4326 - for WGS 84 (Long and Lat)

Save the changes to the MT_ADMIN_SETTINGS table and run the Scale Print tool. Your Scale Prints will now be able to access OSMM geometry projected to the chosen SRID.

On first printing OSMM using 4326 projection, you may notice that there is a discrepancy between the area shown in the PLACE box in the MapThat Scale Print window and the actual area being plotted in the output Scale Print pdf. To resolve this issue you will now need to update the MTTileOS.py file where there is a reference to using 4326 projection.

Using Notepad++ open the MTTileOS.py file and find line 109, which should currently state - if srid != 4326:

Make the following edit to the existing line by changing the value to now read: if int(srid) != 4326:

Test the Scale print tool and the output Scale Print PDF map will cover the same geographic area as the PLACE box within MapThat.