Thanks to an alert friend, I have discovered a very nice piece of software that rivals my present chart plotting program. It's called OpenCPN and has these features:
* GPS/GPSD Postition Input
* BSB Raster Chart Display
* S57 Vector ENC Chart Display
* C-MAP Vector Chart Display (CM93/2)
* AIS Input Decoding
* Waypoint / Autopilot Navigation
* International Language Support
* Cross-platform support
* Grib Weather Overlay
It works on Windows, Linux, and Mac operating systems. One of my favorite features is being able to see the direction and strength of local currents overlayed on the chart (orange arrows):
Right-clicking on the tail of the current arrow brings up a graph showing the current strength and direction for the day. One can also scroll back or forward in time to different days.
Plus, you can turn on tide tables, and open detailed tide graphs.
As I've used Memory Map Navigator for chart plotting for several years, I'm curious to see how this program compares. One of the important features of my present program is the ability to display other shipping, using the A.I.S. system.
OpenCPN includes this key feature.
I found installation and setup very easy. There's also a manual available online, which I plan to read soon :-)