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## Waypoints

A position format and a datum for presenting the position of each waypoint are chosen by the user. Changing the format or the datum may be made at will, but too many conversions may degrade the accuracy of the data.

The position formats and datums of all the waypoints in a group can be changed in a single operation as described below.

Some information that may be relevant for choosing a datum is given when describing how to define new datums.

The following position formats can be used:

- `DMS` for degrees followed by minutes, both as integers, followed by seconds as a floating point number; the degrees value can be preceeded by a minus sign or one of the letters `N` or `S`;
- `DMM` for degrees as integer followed by minutes as a floating point number; the degrees value can be preceeded by a minus sign or one of the letters `N` or `S`;
- `DDD` for degrees as a floating point number; this value can be preceeded by a minus sign or one of the letters `N` or `S`;
- `GRA` for centesimal degrees as a signed floating point number;
- `UTM/UPS` for easting zone number, northing zone letter, easting and northing of Universal Transverse Mercator or Universal Polar Stereographic coordinates.
- one of the available grid systems, either predefined or user-defined, with a zone identifier (void for some grids), a easting and a northing (both in metres by default; user-defined ones may be in feet). The predefined grids are:
  - `BMN`: Austrian "Bundesmeldenetz";
  - `BNG`: British National Grid;
  - `BWI`: British West Indies grid;
  - `CMP`: Portuguese military maps grid;
  - `CTR`: Italian Carta Tecnica Regionale;
  - `GKK`: German grid ("Gauss-Krueger-Koordinatensystem")
  - `IcG`: Iceland grid;
  - `ITM`: Irish Transverse Mercator;
  - `KKJP`: basic Finnish grid;
  - `KKJY`: uniform Finnish grid;
  - `Lamb93`: French Lambert 93 grid;
  - `LambNTF`: French Lambert NTF ("Nouvelle Triangulation de France") grid;
  - `LambNTFe`: French Lambert NTF ("Nouvelle Triangulation de France") zone II étendue grid;
  - `LV03`: Swiss grid in the LV03 frame;
  - `RDG`: The Netherlands grid;
  - `SEG`: Swedish grid;
  - `TAlbers`: Teale Albers grid (used in California, USA);
  - `TWG`: Taiwan grid.
  More details on these grids can be found below.
- `MH` Maidenhead locator coordinates: this is a special kind of grid used mainly for specifying the position of radio stations, each smallest subdivision being 5 minutes in longitude and 2.5 minutes in latitude. This means that conversions from other position formats to this one will most probably loose accuracy.

The altitude for a waypoint is given as a (possibly signed) floating point number in either metres or feet, depending on the existing option for this.

A symbol and a display option are also chosen for each waypoint. GPSMan symbols and display options may not all be supported by the receiver. When GPSMan is aware of this a tilde `~` will appear before the symbol name in the symbols menu. Symbols and display options not supported will be transmitted to the receiver as the default values; if these are also not supported, the symbol will be transmitted as a waypoint dot, and the display option as "Symbol & name".

User-defined symbols of Garmin receivers will be shown as waypoint dots as there is no documented way of importing their images from the receivers. Their code numbers are kept internally and in GPSMan data files. These symbols do not appear in menus and therefore cannot be selected.

The symbols menu can have a sub-menu defined by the user: more details below.

Symbols of all the waypoints in a group can be changed in a single operation as described below.

A map background image name can be given for each waypoint, so that when the waypoint is displayed on the map window the named image is automatically loaded if the map is empty. See below for the details.

Creating a waypoint can be made as for other items from menus and also in the following ways:

- at a given distance and bearing in relation to an existing waypoint, from its window; the maximum allowed distance is about 20000km (more precisely, pi times the ellipsoid semi-major axis); if the distance is greater the new point will coincide with the old one;
- from the map, if the map has been geo-referenced: see below;
- from a track, either as one of its points, or by taking an average of the coordinates: see below;
- from the waypoints in a group by taking an average of the coordinates: see below;
- (Garmin variant only) from the travel menu, by taking the coordinates of the last point in the real-time log if there is one: see below.

The position of a waypoint displayed on the map can be changed there through a menu, as described below.

Clusters of waypoints can be created by giving a group of waypoints to be used as centres: see below.

|  |  | Waypoints