Even though it has been part of Pocket GTViewer since version 3.0.x.20, one of the lesser known features of Pocket GTViewer is the Reference Point. The Reference Point provides a very simple function; it allows you to place a fixed point in your map view and a special arrow on the GPS indicator will always point toward the Reference Point.
The Reference Point is found under Menu/Options/Reference Point and presents a dialog like the following:
The Reference Point dialog provides 2 ways to place a Reference Point in your map. The Place Button allows you to interactively place the Reference Point by tapping a point in the map view. The At GPS Point button (which is only enabled when the GPS is tracking) will place the reference point at the current GPS position. Two more options are available to provide more information while the GPS is tracking with a Reference Point. Show Path will draw a dashed line between the GPS indicator and the reference point. This line is sometimes more informative than just an arrow pointing in the direction of the Reference Point. The Show Info option will cause the Distance and Bearing from the GPS Indicator to the Reference Point to both display at the top of the map view. The following screenshots show the Reference Point with the Show Path and Show Info options enabled as well as the Decaying GPS trail. The GPS indicator will use a Blue Arrow head to point to the Reference Point while a Red Arrow head indicators the current heading.
The following screenshot show the Reference Point arrow on the GPS indicator without the Path:
There are also several other options available for the Reference Point. In the .GTM file, you can add several entries to the Additional Properties section to control certain aspects of the Reference Point.
RPCol can be used to specify the color for the Reference Point. The default is Blue. Color is specified as a RGB component color value.
RPStyle can be used to specify the line style id used for the line connecting the GPS Reference Point to the GPS cursor. The value can be 0 to 7. The default is 2 (dashed).
RPWeight can be used to specify the weight of the line connecting the GPS Reference Point to the GPS cursor. The value can be 0 to 15. The default is 2.
RPPos can be used to specify the location of the default position of the Reference Point, such as your home office, etc.
RPProp is can be used to specify the default options (Show Path and Show Info).
The Reference Point can also be controlled via the Developer’s Framework and the Reference Points current location is always available to external applications.