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How do I add online background mapping to my project? The internet provides access to a number of sources of map tiles that can be accessed on demand,
these can be utilised to provide accurate and up to date background mapping for your project. This
can help with model building, ensuring hydraulic units are correctly located. It can also be used to
enhance model results, e.g. using aerial (satellite) photography to overlay flood extent results over.
There are multiple options available in Flood Modeller for defining background mapping:
WMS layers – Flood Mapper provides a tool to create a new GIS layer that utilises a web
mapping service via its URL. Further guidance on this can be found in the section “How to
Add a WMS Layer to My View?”
Online mapping – You can connect your map view to one of a fixed number of freely
available online mapping services included within Flood Modeller. This fixed list is made up
from Open Street Map and the multiple maps provided by Bing (i.e. streets, satellite images
or a hybrid of both).
How to add online mapping to my view? In this section the method for adding online base maps to your map view will be explained.
1. After creating a new project or loading an existing one ensure some geo-referenced data are
loaded into your map view, e.g. a 1D network or any GIS dataset added to the Layers panel.
2. The base mapping options are provided in a dropdown menu accessed from the Home tab of
the main toolbar
3. Click on the Base Map button to access a menu of available mapping options
4. Click on an option to add it to your map view as background mapping. Note that this will not
add any new datasets to your Layers panel.
5. The base mapping requires a geo-projection to be defined for the map view. If your project
currently does not have a geo-projection associated to it then you will be prompted to
specify one. If you click yes to proceed then a new window is displayed that lists all available
projections and enables you to select one. Clicking OK assigns the selected projection to your
project (and closes the geo-projection window).
Your map should now display the selected mapping data as a background to your map view
(always behind other layers). Note that this functionality requires an internet connection to
work (and may make the map view respond slowly if the internet connection is slow).
Note that you can review and edit your project projection setting by clicking on the Start tab
of the main toolbar. The current projection setting is displayed on the Info page and a
button is provided to access the projection selection window (as shown above).
Click here to access the
base mapping options
All available projections
listed here Click OK to add selected
projection to your project
If you know the projection
code then just type in here
Currently selected
projection shown here
6. Your selected projection should now be displayed on your Project Info page (accessed from
the Start tab in main toolbar). Remember to save this setting by saving your project. Note
however that the selected background mapping will not return automatically when you re-
load the project in a later session. Flood Modeller’s default starting setting is to show no
background mapping.
Updating the background mapping As you pan or zoom to different locations the background mapping will update automatically.
Furthermore the level of detail shown will increase as you zoom in to a smaller area (and decrease as
you zoom out).
You can change to a different background map source by selecting a different option from the Base
Maps dropdown list. Note that you might need to change the map extents to trigger this update in
the map view, e.g. pan a small distance.
How to add a WMS layer to my view? In addition to providing access to online base maps, Flood Modeller is also compatible with web
mapping services (WMS layers). These are online GIS data repositories that you can link your map to.
The relevant background data to your map extent will then be downloaded and added to your map
view (behind other layers). This section describes how to add a WMS layer to your map view.
1. Start Flood Modeller and either load an existing project that you want to work on or define a
new project.
2. In order to utilise a WMS layer you require the URL for the website providing the data (there are
various free sources of data available that an internet search should yield).
3. Once you know the URL for a WMS you need to set up a WMS layer to display these data on
your map. Access the New GIS data button and select the WMS Layer option.
4. A new window is displayed. Select the New button to start defining your WMS layer details.
Enter the WMS URL in the space provided (plus any associated username and password if they
are required). Give you layer a name, so you will recognise the data source later.
5. With a WMS URL address defined and highlighted in the WMS server table, click OK to proceed
to generate a WMS layer in your map view. This will have all associated layers (applying to all
zoom levels) embedded within it, so all of these data will be available in your map. However, in
some cases this will be more data than is required and loading all layers will lead to slower
performance (as you zoom and pan around your map and the data needs to refresh each time
from the host web server).
Therefore you have the option to only select a subset of layers available from the WMS server to
add to your map (or even just one). To view the available layers click the Validate button. The
layers will be listed in the Layers panel as shown below. Select layers by clicking in the adjacent
box (so it is ticked). The details of the highlighted layer are displayed to the right of the panel.
Flood Modeller provides a save button on the WMS layer definition window. This allows you to
save the WMS web server reference (or multiple references) that you have defined in the
interface to a standalone file (xml format). This can then be imported into other projects or
distributed to other users. The interface also provides a load button that enables you to browse
to a saved WMS reference file. Note that when a WMS xml file is loaded in it will only populate
the upper table in the above interface with WMS URLs. You are still required to select which to
utilise and then which layers within this to select for the WMS layer to be added to your map.
6. When you have defined your subset of layers, click the OK button. A new WMS layer will be
created in your map view. This will include all data layers selected in the previous step. The 1D
networks in your project will always be displayed on top of this layer, but the WMS layer will be
added above other GIS layers already displayed in your map. You can drag the WMS up and
down the layer order (to the left of the map) to move it above or below other layers.
7. It is not possible to switch individual layers within a WMS off and on within your map view.
Therefore if you require this functionality you will need to create multiple WMS layer files in
your map, with each one referencing a different layer from the WMS server.
8. Once you have added your GIS data to your map view you can “move around” the view using the
standard map tools provided:
Zoom in – Click toolbar button to activate and then drag a rectangle on the map to define
the area you want to zoom to. Click the button a second time to deactivate the zoom
function.
Zoom out – Click toolbar button to activate and then click on map to zoom out a fixed
amount. Click the button a second time to deactivate the zoom function.
Zoom to extent of selected layer – right-click on a model network in the project view or on
any layer in the Layers panel and select the zoom to option from the displayed menu.
Zoom to full extent – toolbar button that sets zoom level to show all layers currently loaded
in map.
Fixed zoom in / out – on map “+” and “-“ buttons that zoom in or out a fixed amount
(centred on the current view centre)
Pan – Click on toolbar button, on map button or right-click on map and select Pan from
displayed menu. The mouse cursor will change to the pan icon. You can then move about
the map by dragging the mouse with the left click button depressed. Select the pan function
again (from any location) to deactivate function.
9. If you double-click on the layer in the Layers window (or right-click on it and select Properties
from the displayed menu) then you can access the WMS layer properties window. This enables
you to edit the following key settings to affect how the WMS data are displayed:
WMS dataset added to Layers panel.
Move WMS to bottom of list to ensure it
displays behind your other GIS datasets
Transparency – you can vary the opacity of the layer from 0 to 100% (fully transparent, i.e.
not visible in the map)
Refresh timeout – you can set a maximum time that Flood Modeller will try to access the
web server to update the WMS map view. After this time Flood Modeller will stop trying to
access the internet and return control to you (the interface is locked while the map is
updating). This is useful if your internet connection is unreliable. The default setting is 60
seconds.
Example WMS data In the UK the Environment Agency have made some of their GIS datasets available as WMS. These
can be accessed free of charge from their website:
https://data.gov.uk/data/search?res_format=WMS
An example UK EA dataset reference is shown below (accessed by clicking on any item in the list
provided by the above link):
If you click on the “Link to WMS” hyperlink you should see the WMS data defined in XML format, as
shown in the example below. To build a Flood Modeller WMS layer you need to copy the
appropriate “OnlineResource xlink:href” and use this as the URL address in the Flood Modeller
create WMS layer tool (as described earlier in this document).
Click here to access
WMS URL data
“OnlineResource xlink:href” field
provides URL to use in definition of
new Flood Modeller WMS Layer