How are chart notes and legends found on a raster chart?
Hydrographic offices provide the coordinates of a rectangle surrounding each note, legend, tide box or channel depth table. They also provide reference point coordinates for each note. RCDS software places an unobtrusive (or invisible!) icon at the reference point. When the icon is “picked” by the mariner, a second small window on the chart opens, displaying the note. This method would allow notes to be displayed automatically as a mariner’s ship approaches the coordinates of the reference points.
