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Landscape Data Visualiser Map Functions
There are several map functions available for users to search for data. These include (in vertical order):
Show/hide map button
Zoom in
Zoom out
Zoom to full extent
Zoom to selected layer extent
Bookmark current extent
Select saved extent
Grid transparency selection:
Solid circle = no transparency
Half filled circle = partial transparency
Empty circle = full transparency
Bookmarking and saving spatial extent
Bookmarking a spatial extent helps users download data for a specific area, especially when the data file is large. Users do not need to log in to bookmark an extent.
To bookmark an extent, zoom to the desired area and click the “bookmark current extent” button 
Then, name the extent and choose to save either a drawn bounding box or the current extent.
Bookmarking a spatial extent will only save the extent locally in the user’s browser cookies. If the user opens the same page from a different browser, private window of their browser, or deletes their browser history, then the saved extent won’t be available.
If users select Draw Bounding Box, they will be able to draw a rectangular or square shape on the map. Once a rectangle has been drawn, the map will automatically zoom to this extent. Users can then choose to either save the selection or cancel and try again.
Selecting Saved Extents
To select a saved extent, users should click on the Manage Extents button 
Once a saved extent is selected, the map will automatically zoom to that extent.
Note that the extent saved is not specific to any particular map layer. It is simply a saved level of map extent which users can utilise for any dataset they add to the map.
Managing Map Extents
Users can also edit or delete their saved extents, by clicking on the “Manage Saved Extents” button in the form which generates when they wish to select an extent to navigate to.
This will generate a list of the users saved extents as shown below.
To delete a saved extent, users can click on the delete button next to the extent name. Note that there is no confirmation of deletion on this action and once clicked, the extent is immediately deleted.
To edit a saved extent, users should click on the name of the extent. Users can also choose to zoom to an extent if it is selected from this form.
Once selected, the name or bounding box coordinates of the extent can be edited. Users are then able to save changes.
If changing the name of the extent, users will see the new name in the list of extents immediately upon saving.