|  |  | Basic concepts

## Basic concepts

Here is a list of a few terms that will be used below.

Waypoints, routes, tracks and laps are examples of data used in GPS receivers.

- a waypoint (sometimes abbreviated to WP) describes a precise location through its geographic coordinates
- a sequence of waypoints is called a route (RT) and is defined by the user
- a track (TR, also called a trail in Lowrance receivers) is a sequence of track points (TPs) recorded by the GPS receiver over a time period and giving the positions, each with a time-stamp, of the receiver during that period, and including if possible the altitude and the depth (both in either metres or feet, depending on the existing option for this)
- a lap (LAP) has a time-stamp for its start, a duration, the total distance, the calories spent, the start and stop positions, and an associated track; a sequence of laps is called a run, and runs are represented in GPSMan by groups that are automatically created when getting laps from the receiver; support for laps in GPSMan exists only for Garmin receivers and must be explicitly selected from the options (receiver parameters) window;

Route stages are the parts of a route between each two consecutive waypoints. Route stages are called edges in Graph Theory, legs in aviation, and links by Garmin. At present, GPSMan deals with three data fields for each stage: a comment, a label (that will appear in the map), and hidden information.

Data items refer to the elements stored in the GPSMan data-base. Apart from the data items used in GPS receivers GPSMan also works with

- polylines (LN), also called polygonal lines, that are similar to tracks but have points (LPs) without time-stamps. Polylines are mainly used as background in the map window
- groups (GR) can be seen as sets of items, or alternatively as directories/folders containing items. They can be used to collect together items that are related to each other, they allow for operations to be performed on a set of items and they can be the result of operations yielding a set of items (for instance, the result of a search).

Track and polyline segments are subdivisions that, in the case of tracks, normally indicate that there were time gaps in which the receiver got no position information. The representation in the map of a track or polyline having different segments is a polygonal line that is interrupted between each segment (segments with a single point will hardly be visible). Segments are defined by their starting points and in the track or polyline edit window it is possible to mark or unmark each point (except the first) as being a segment starter.

Comments and remarks (NB) can be specified for some types of items. The difference between them is that comments can be got from and put into the GPS receiver, while remarks are only kept by the interface and may be saved to and loaded from GPSMan files. The characters allowed in a comment, as well as its size, depend on what the receiver accepts with the exception that GPSMan will replace any newline by a space. In remarks the only constraint is that no blank lines are allowed.

A map background image name can be associated to each data item except for laps and groups, so that when the item is displayed on the map window the named image is automatically loaded if the map is empty. See below for the details.

Forgetting a data item means deleting it permanently from the data-base.

Input/Output operations in GPSMan have the following names (see below for the definitions of the GPSMan file formats):

- loading from and saving to files in GPSMan format;
- getting from and putting into the GPS receiver (this corresponds to the terms downloading and uploading, respectively, used in other software);
- importing from and exporting to files in a foreign format. Currently recognized formats are given below.

|  |  | Basic concepts