Routes and Marks

Information about routes and marks is accessed through the "Tools→Route Manager" window.

From the Route Manager, you can also modify the options for each route: Tools→Route Manager→right-click on a route→Route Options. The most important options are the start time of the route and the polar data file.

The Route Manager lists the routes and their lengths in nautical miles.  In addition, if wind data has been loaded that covers the start time for the route, then the estimated time of arrival (ETA) at the last route point is displayed, and the corrected handicap time enroute (ETE) is shown.  The handicap formula can be modified from the options window.  The handicap formula is any formula using two variables, "$time" and "$dist".  The former refers to the uncorrected ETE (in decimal hours) and the latter the distance in nautical miles.  So for a distance handicap formula given by, say, +1/2 a minute per nautical mile, your corrected time formula would be "$time + (0.5/60)*$dist", giving corrected time in hours.

You may choose to see detailed information for each route, by double-clicking on a route in the list, or using the "details" button.  This gives heading, time, distance and more info for each leg of the course.

In the route details window, GC Course means the initial course if the leg is to be sailed as a great circle.  The GC course will change as you progress along the leg, but presumably you are using a GPS to sail the course, and the GPS will automatically adjust.  "Rhumb course" means the constant course you would use to sail that leg along the rhumb line.   The rhumb line is the straight line drawn on a Mercator projection chart.  (Pre-GPS, a navigator would divide a great circle course into a sequence of short constant-heading rhumbline legs.)

Additional route options:

• Visible:  if unchecked, the route will not be displayed.
• Nondestructive:  if checked, optimization will create a new route.  If unchecked, it will overwrite the old route.

Making a Route Point Refer to a Mark

You can make a route point be located at a mark by entering Edit mode, right-clicking on the route point, and changing the mark field to be the desired mark.  This is called a mark reference.  The advantage of a mark reference is that if the mark is moved, then all route points that reference that waypoint will also be moved.  Also, if it’s a course mark, you don’t need to keep typing in the coordinates, or carefully moving the point on the chart.  Just edit the point to set the mark reference, and it instantaneously moves to the mark’s location.

Importing Position Reports

Race committees often provide the positions of all competitors by email.  BLUEWATER has a function to import these reports and append the positions to existing routes.  For example, here is a position report for competitors in division 2 of the 2007 Transpac race.

Suppose you are sailing on HOLUA and you are keeping track of your competitors in division 2.  You have created routes for HUGOBOSS II, LUCKY, etc. that mark their daily positions up till now.  You want to include the July 23 positions.

Select File→Import Positions. You will be asked for an import file, an import field specification, and the import field separator character(s).  The import specification describes the layout of a position data, such as in this line:

2A,HOLUA,97656,7/23/2007 06:00,22.5667,-145.2833

The fields necessary for BLUEWATER are the route ID (which should match the name of an existing route in your race), the latitude, longitude, and the date-time fields.  All other fields in the line are junk.  The import specification is a list of keywords taken from the set:

id, date, time, datetime, lat, lon, latu, lonu, junk. 

So for Transpac 2007 position reports, the import spec reads:

"junk id junk datetime lat lon". 

The field separator character is ",". 

“datetime” refers to a field in which the date and time are combined, as in the above example.  “latu” and “lonu” refer to latitude and longitude values in the special format “dd:mmsss”.

The position file is scanned, and any line that does not look like a position report line (e.g. mail header line) is ignored.  For any ID that can be matched to a loaded route, the position is appended to the route.  For unmatched IDs, you are offered a choice of creating a new route with that ID, or ignoring them.

The import function can only handle positions that are provided as a single line of text fields separated by some consistent characters (such as commas, spaces, or tabs).  The scanning is not guaranteed to be perfect, and you may need to delete email headers etc. before trying to import.  But the above example imports just fine so with any luck you'll be mostly okay. 

You can add a default import file spec via the preferences, Tools→Preferences.

If the import file contains multiple positions with the same id, then each successive position is added in order to the end of the route.  This gives yet another way to create a route -- simply write a little text file of positions with the same route id, and then import it.