Projections and Coordinate Systems

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MapPoint only works with geographic decimal longitude,latitude coordinates using the WGS84 datum. This is the same coordinate system that is used by Bing Maps and Google Maps, and is specified by the KML standard. MPSuperShape is capable of converting ESRI shapefiles and MapInfo MIF files to/from other coordinate systems and projections.

 

When importing an ESRI shapefile, MPSuperShape will read the projection and coordinate system information from the accompanying PRJ file (f present). MPSuperShape should be able to read most of the 'new style' ESRI PRJ files which are similar to the OGC WKT standard but with some name changes. MPSuperShape can also read some of the older (Arc/Info 7.x) style PRJ files.

 

For MIF files, MPSuperShape takes the coordinate system information from the header.

 

MPSuperShape can also export to these formats using different projections and coordinate systems, using one of four different options:

 

Geographic Coordinates on the WGS84 Datum
UTM (Universal Transverse Mercator)
A Predefined Coordinate System
An External PRJ file

 

These are selected in the Coordinate System section of the Export Options dialog box:

 

 

export_shp

 

The "Geographic Coordinates on the WGS84 Datum" is simply the MapPoint standard coordinate system. This is usually the default. Selecting one of the remaining three options will enable the button in the lower right. The exact caption on this button will vary according to the option.

 

The "UTM (Universal Transverse Mercator)" option will allow you to select a UTM Zone for the output coordinate system. Press the Select Zone button to display the Select the required UTM Zone Parameters dialog box:

 

export_utm

 

The UTM coordinate system has 60 zones and two hemispheres. Select the required zone and hemisphere. MPSuperShape also lets you select one of four datums (WGS72, WGS84, NAD27, NAD83). MPSuperShape does not support the corresponding Universal Polar Stereographic (UPS) systems, due to the poor handling of near-polar coordinates by MapPoint. Note: MPSuperShape will only successfully export coordinates that are within the selected zone and one adjacent zone on each size. Any coordinates outside of this area will cause an error and halt the export process.

 

The 'Predefined Coordinate System' option allows you to select a coordinate system which has been predefined in MPSuperShape. Press the Select System button to display the selection dialog box:

 

export_predefined

 

MPSuperShape currently has the following coordinate systems pre-defined:

 

Geographic Coordinates using the WGS84 Datum
British Ordnance Survey National Grid using the OSGB36 Datum
Geographic Coordinates using the OSGB36 Datum

 

The final 'External PRJ File' option allows you to specify a custom projection and coordinate file using an external 'PRJ' file. Select this option, and then press the Select PRJ File button to select the PRJ file.  This option is only available for the ESRI shapefile export option. The PRJ file is not copied directly, but is read and re-generated.

 

The 'External PRJ File' option is not available for MapInfo MIF files due to the relatively limited range of datums supported by MapInfo. Most common datums are supported by the MIF format, so if requested, we can add new datums to the list of pre-defined coordinate systems.

 

All PRJ files created by MPSuperShape use the later ESRI format that is based on the OGC 'WKT' format but with some slightly different internal names.