Magellan Triton GPS receivers have an option to load National Geographic Raster maps. But Magellan left specification of the raster map format unopened. People from tritongps yahoo group made extensive study of the format. I used their findings and my own research to develop a program to create custom raster maps compatible with Triton GPS receiver and Magellan's Vantage Point software.
RMP file can contain many maps (I tested 15), each map will be shown at several zoom levels in dependence on the scale of each map. Triton does it automatically. All we need isjust load the image (or several images), calibrate it(them) and create the *.rmp file.
1. File-Import image(s) loads bitmap images (currently jpg, gif, bmp). Their names appear in the grid, together with the image size. To move the map use scrollbars or move with mouse with holding left button pressed.
2. Each image should be calibrated. Select one of the calibration points (color "targets" at right), select some location in the image and double click. Then enter coordinates in one of three formats. Do not forget N/S and E/W! Then select another point, and repeat. As many as 5 points can be used, 2 are mandatory. More space between points produce better accuracy. More points used, better accuracy you will get. After 2 or more points are inserted. Click "calibrate" button. This image will be calibrated and "Y" will appear in the last column of the grid. Do the same for all images.
3. At any stage Image(s) and corresponding calibration information can be saved File-Map-Save Selected mp (All maps) to custom *.gba format. This file contains links to the images (not the images themseves) and some calibration information. The file(s) can be loaded and in this case calibration is no longer needed, because it is saved in the map file.
4. When image is loaded into the program, file name appears in the first column of the grid. It can be changed by double click to the corresponding cell. If map is saved and reloaded this new name will be indicated.
5. If there are several maps, they can be briefly overviewed with "Overview map" menu. Relative location of the maps will be shown.
6. After all maps are calibrated, there should be "Y" for all maps in the grid. Click "Create RMP" and *rmp file will be created.
Maps for Triton GPS should be in WGS84 coordinate