Georeferencing and Real World Coordinates
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Many maps are georeferenced, and this makes it possible to determine real world coordinates as well as longitude and latitude for the controls and other objects that can be placed on the map.  Determining longitude and latitude for controls is very useful when exchanging data with GPS based applications, such as for example route choice apps.


Condes supports geo-positioned maps and automatically reads georeferencing data from the map file if such data is present:


OCAD map files can contain georeferencing data, which Condes can use right away.   If the OCAD map file has configured a reference coordinate system, then Condes can translate the map's coordinates to longitude and latitude.  From OCAD 9 and newer, the reference coordinate system can be configured directly in OCAD.  For OCAD 8, the map can be geo-referenced, but the file does not contain information about the reference coordinate system, so Condes uses the reference coordinate system configured in Application Settings.  OCAD 7 and older does not contain georeferencing information.


Bitmap files can be accompanied by a so-called "World File", which contains the real world coordinates for the top left corner of the bitmap.  A World File has the same file name as the bitmap  file, but it has a different extension - for example, the World File associated with "MapFile.jpg" is "MapFile.jpw".
Condes can use the coordinates in a World File to geo-position the map.
The World File does not contain information about a reference coordinate system, so you need to enter the coordinate system info directly into Condes.  A number of web sites can help you determine this.  Normally, the reference coordinate system is UTM / WGS84, in which case you need to enter an "UTM zone" in Condes. Search for "UTM Zone" on the internet.   If Condes finds a World File, it asks you to enter the UTM zone or another reference coordinate system.  There is a setting in the Application Settings dialog that lets you save a default UTM Zone to be used for bitmaps.


GeoTiff files is a specific type of TIFF bitmap file, where the georeferencing data is embedded in the file.  Condes automatically detects the presence of georeferencing data in the file and uses it.


In the Course Layout Editor, the real world coordinates for the mouse pointer is shown in the status bar below the map pane, when the map is georeferenced.


When exporting, Condes puts the real world coordinates for each control into the file:


IOF XML files.  If the latitude and longitude are available, then these are used.


Bitmap files.   A world file with the same name, and appropriate extension, is created.  The world file contains the real world coordinates for the top left corner of the map.  The map file's real world coordinate system is used.  If the format is Tiff, GeoTiff information is included in the exported file.


SVG files.  If the latitude and longitude are available, then these are used.


KMZ, KML and GPX files.  Latitude and longitude must be available.  This means that the reference coordinate system must be defined.


PDF files.  When a reference coordinate system is available, and Condes can translate coordinates to latitude and longitude, Condes will geo-reference maps in the file, according to the "Geospatial PDF" specification.  See Geospatial PDF files.


In order for Condes to provide georeferencing data in the exported file, the map must be georeferenced.  In order to provide longitude and latitude, the real world reference coordinate system need to be defined.

World File
A world file is a six line plain text file used by geographic information systems (GIS) to georeference raster map images. The file specification was introduced by Esri, and consists of six coefficients of an affine transformation that describes the location, scale and rotation of a raster on a map.