#3 Request to add support for variable-barrel task handicapping

[Martin Gregorie]

Here in the UK we've started using 'variable barrel' tasks as a popular way to allow a wide range of glider types to fly the same task. The idea is to declare a single 3 or 4 turn racing task using barrel turnpoints but to apply handicapping by setting the turnpoint barrel size to suit the glider's handicap. Each pilot is given his barrel size at briefing, sets it into his navigation computer and flies the task. This simplifies scoring because the fastest time wins, with the scoring systrem only having to check that each glider that completes the task has a fix in every barrel: the standard scoring programs can be scripted to do this.

All the common navigation programs, e.g. LK8000, XCSoar and SeeYou Mobile can already handle the required barrel sizes, which range from 500m radius for the highest performance glider out to several km for the lower performance gliders. The last variable barrel task I flew assigned me a 4.2km radius: I fly an H.201 Standard Libelle while other pilots were flying Discus 2s and Duos.

So, here's my request. Please change the Options menu so that the required barrel radius can be typed in as metres or km, that would do the trick. The ideal would be if Options was to allow start/finish line length and turnpoint default radius to be set separately and the Task Editor could be used to override the turnpoint radius for individual turnpoints. I think the task setting rules allow some turnpoints to have different radii, e.g. the 'steering' TPs that are sometimes used to control the finish direction would typically be 500m radius for everybody.

As an actual example I've attached my trace from the last variable barrel task I've flown. In case you're wondering, I didn't finish the task because thick top cover arriving from the west caused me to abandon about 10km short of Towcester. Look at the first turnpoint (Littleport, out to the east), where it looks as though I turned very early. However, recalling that my handicapped barrel radius was 4.2km, if you create a KML file and look at it on GoogleEarth you'll find Littleport is around 4km NE of where I turned, so was in the barrel.

This trace nicely shows another problem: that where the task is bigger than the flight path, the default scaling prevents the whole task from being seen. So far I haven't been able to find how to zoom further out. So, please consider doing one of the following:
1) leave the default size as is, i.e. fitted to the flight log, and provide a way to zoom further out so everything can be seen.
2) rescaling the display so it includes all of the flight path and all of the task plus the FAI sectors/barrels.

Note: unfortunately its not possible to extract the barrel size from the IGC log because the C record doesn't include that information. Hence my request for changes to Options and the Task Editor.

[Hannes Krueger]

In 1.10 there is support for a 'radius factor' which can individually set for each waypoint in the task editor. Using the 1km cylinders (or cylinders+FAI sectors) option, you can enter your variable barrel in km for each wp.

in your example the shortest logged distance to littleport is 4.37 km, at 12:36:47. Is that correct?

'zoom to task' is on the todo list (as well as save and load task)
In the mean time you may use the 'right mouse button zoom' and drag the zoom box out of the window. that way you may be able to zoom over the edge.

[Hannes Krueger]

A 'zoom-to-task' (Key T) is implemented in todays development version:
http://pc12-c714.uibk.ac.at/GPLIGC/download/develop/

Also, a user configurable border zoom_border in .gpligcrc