OpenCPN as lineplanning tool

[TomSeeker]

Hi, looking to my OpenCPN software to plan some survey lines and export to other Nav solutions. The survey lines must be parallel lines that are equal length. Right now, the process is to use the route tool to create routes, and use the measure tool to fine-tune where those waypoints end up. There has to be a better way! Picture attached of a few lines. Haven't found a plug-in to help create and "copy" lines over, but I'm sure someone has figured this out before! Would be the ultimate Nav software if this was possible (already is, really).

[Hakan]

Tom....
You may like to explore the SAR plugin. Sound like what you're asking for.
In the Options->Plugins.

Moro info here.

[Antipole]

Originally Posted by TomSeeker

Haven't found a plug-in to help create and "copy" lines over, but I'm sure someone has figured this out before!.

This would be straight forward using a script in the JavaScript plugin.

There is a built-in function to calculate a position a given vector (distance and bearing) from a given position.

toPosition = OCPNgetPositionPV(fromPosition, vector);

So you can easily create a two-point route with start and end points a given vector from an existing route.

All the required information is in the User Guide for the plugin.

[Antipole]

Here's a JavaScript for you that does exactly what you want. I have tested it.

As configured, it assumes you have created the first 'route' with the name Line0.
You configure things at the start - such as the number of lines and their spacing.
See the plugin User Manual to understand the OCPN interfacing.

You can modify as required - enjoy!

name = "Line"
number = 3;	// number of parallel lines to add
space = 1;	// line spacing in nm

// find base line
baseName = name + "0";
routeGUIDs = OCPNgetRouteGUIDs();
found = false;
for (i = 0; i < routeGUIDs.length; i++){
	route = OCPNgetRoute(routeGUIDs[i]);
	if (route.name == baseName) {
		found = true;
		break;
		}
	}
if (!found) throw("Cannot find base line ", baseName);
if (route.waypoints.length != 2) throw("Route " + route.name + " does not comprise just two waypoints");

// calculate the vector to move each waypoint
linebearing = OCPNgetVectorPP(route.waypoints[0].position, route.waypoints[1].position);
vector = {bearing: (linebearing.bearing+90)%360, distance: space};

// create extra lines
for (i = 1; i <= number; i++){
	route.name = name + i;
	start = route.waypoints[0].position;
	end = route.waypoints[1].position;
	route.waypoints[0].position = OCPNgetPositionPV(start, vector);
	route.waypoints[1].position = OCPNgetPositionPV(end, vector);
	delete route.waypoints[0].GUID;	//need to delete this so new waypoint created
	delete route.waypoints[1].GUID;
	OCPNaddRoute(route);
	}

[rgleason]

I think you should try OcpnDraw plugin. It has several drawing tools that will help.

[rgleason]

I like antipole's solution. Ocpn-draw does have a parallel line tool used for creating convenient navigation offsets.