Zone plugin

The zone plugin lets you define regions of the radar scan and process them in special ways.  There are two types of zones (so far):

• exclusion zone:  samples here are classified as "COLD" regardless of their score, and so no blips will be found in this zone.  Useful to exclude a known area of persistent false blips, such as might be due to waves on a lake
  
• special zone:  blips here are filtered using a zone-specific set of parameters

Recent changes:

29 Nov. 2009 (radR 183):   use the right mouse button to get the zone menu, not the middle button. (Some mice / laptops don't have a middle button.)

A zone consists of one or more segments that look like this:

 

 

 

 

Zones can be displayed by using "Show zone..." from the zone menu. This will put radR into "Tk plotting mode".

To edit a zone, click on a segment with the right  mouse button and choose "Edit zone".  This will display "control points" at the segment corners. 

While editing the zone in the plot window, you can reshape segments by dragging on their arcs, sides, and corners.

If you hold down the Alt key while dragging, the segment is moved rigidly rather than resized.

 

 

 

The zone plugin menu looks like this:

About will list the currently defined zones and give their segment coordinates.

Raw data in the exclusion zone can be made black.  Otherwise, they plot as cold.
You can create a new zone or show an existing zone.
Zones are not effective unless they are enabled by selecting them using "Enable zone"

For special zones, you may copy current blip filtering parameters or edit them directly.

You can attach a description to a zone using Change zone set description.

You can save and load zones from files so they can be used in other radR sessions.

There are further tools on the segment menu which appears when you click the right mouse button on a segment
while not in edit mode (i.e. when no circles are drawn at segment corners):

 

You can turn on zone edit mode.

 You can hide a zone.

 

A zone's blip-filtering parameters are only used when the zone is enabled.

To change the segments in a zone, you have to enter zone edit mode, in which the right-button menu changes to this:

You add segments to a zone using New segment or Clone segment. 

You can force the segment to have the shape of a pie piece using Range ->0. 
You can extend the segment out to the edge of the data using Range->max.

You can use the mouse's current range as either the min or max range.

You can force the segment to be a ring or disc by using Full circle.

You can undo changes made since you last entered edit mode.
You can reprocess the scan to see the effects of editing the zone.

You can delete a segment or delete the entire zone.

The outline colour for a zone can be changed.

 

 Here is a more complicated zone:

It doesn't matter if segments overlap: the zone consists of all points contained in at least one segment. 

 

 

 

 

 

 

 

 

You can specify values for these blip-filtering parameters within each special zone:

 

Which zone is a blip in?

radR uses the blip's x and y coordinates to determine which zone it is in.  These are the x and y shown as part of (x, y, z, t)
in the pointerinfo window, and are the ground coordinates of the blip's "centre of mass", measured in metres east and north of the radar.
The blip belongs to the first zone, if any, which has a segment containing the blip's centre of mass.  When the data source is a blipmovie, rather than raw radar data, blips in the exclusion and special zones are filtered, rather than completely erased.  This means they are still visible on the screen as hot "patches", but no longer as blips.