Download Recorder 6 User Guide

Recorder 6 User Guide
The mapping library on which Recorder’s maps are based does not
support polygons within polygons, so this is actually based on a clever
trick. When you declare that one polygon is a hole in another, both of the
original polygons are deleted and replaced by a single new polygon which
has a boundary consisting of the two previous ones joined by a “zero
width corridor”. This is clearly shown in the illustration. However, this
works just as you would want and an observation that falls within the hole
is correctly classified as outside the polygon.
9.3.3.4 Moving a polygon between layers
Sometimes, usually because you forgot to set the desired layer as the Current Polygon
Layer before importing or drawing a polygon, you want to move a polygon from one
layer to another.
1. Select the polygon you want to move, it will be redrawn in its selected colour.
2. Select Map – Move Polygon to Layer from the menu or click the drop-down
arrow beside the move polygon button on the toolbar.
3. Choose the destination layer from the submenu or from the drop-down menu
in the toolbar. The polygon will be redrawn with the colours and shading for
the new layer showing that it has been moved.
Note that you can only move polygons to an active layer. If the layer is
turned off, its name won’t appear in the sub-menu so you won’t be able to
choose it as the destination.
9.3.3.5 Deleting a polygon
1. Select the polygon you want to delete by clicking on it. The map will redraw
with the polygon in its selected colour.
2. Select Map – Delete Polygon from the menu, or click the delete polygon
button on the toolbar.
3. You will be prompted to confirm that you really want to delete the polygon.
Press the [OK] button to delete it.
9.3.3.6 Linking polygons to a Location
If a polygon on the map represents the boundary of a site that is documented in the
Locations window, then it is appropriate to link the Location to the polygon. When a
polygon is linked to a Location you can:
• Go from the map to the Location entry
• Go from the Location entry to the map
• If you use the facility to get a spatial reference from the map during data entry,
if you click within a polygon that is linked to a Location, then not only the grid
reference at which you clicked is returned to the data entry form, but also the
Location field is automatically filled.
• You can use the map to get a list of grid squares which overlap with the
polygon and fill these in amongst the Location details. These are used to check
that grid references given for observations linked to the Location are correct.
• If you use the polygon to filter records that fall within it for the purpose of
reporting, linking it to a Location gives it a name – which makes the process
much easier.
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