Location maps allow a more global overview of the study area represented on the main map
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The principle is very
simple: these are two maps
in
a
single
setting. The location map will have a
particular feature: we will freeze the area
, the layers displayed and the symbology of these
layers once for all . The only variable will be the area
rectangle which is managed by QGis itself .
To begin, click on the menu Project-> newsettingonpage
or
open
the update manager and create
a
new setting.
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In
the layout setting window, add the main map (menu Add an element ->
Add map) and the location map (idem)
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Note that while the main map
is
named
map 1 and the one location map 2.
You will start by defining the
location map:
1- in the QGis Mapping window, zoom the window contents to
the desired level in the location map.
2- display only the layers you
want
to see in the location map by
disabling
the
display of the other layers.
3- modify , if necessary , the visible
layers symbology. For example, the thickness of
the lines is generally thinner for the
location map than for the main map .
4-check in the layout setting
manager that
the result matches your what you aim for.
To
do that , having selected Map 2, you have to click
UpdatePreview in
the Main Properties panel.
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In
the layers
panel, select the Locklayers box and
Lockthe layersstyle.
To
ensure that there will be no other changes, check the map 2 lock box in the Elements
window
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Your location map is formatted.
Now you are going to take care of the main map by formatting it (zoom, symbology , etc …)
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Once completed the main map formatting,
you only have to connect both maps in a way that the
location map to displays the area of your main map .
To do that you have to unlock map 2, click to select
it , open the Previews panel of your location map.
Click the + button to
add a
preview
in
the list. It will be named
Overview 1.
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To
set the preview,
you have to indicate which area it must
show
. In Map frame , select
Map 1
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You can change the style ( color
, outline, etc. ) by opening the Frame Style
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From that point on, if you
change
the
area of the main map , the extent displayed on the location map
will be modified automatically.