June 25, 2012

Map Options is a special layer that is used to define the basemap displayed in the Spatial Portal, to allow the user to add in their own layer via WMS, download an image of a map, and reset the Spatial Portal.

The basemaps are treated as a single underlying map layer.

Clicking on Map options opens the layer.

The options relating to the Map Options layer are all within the Legend Pane, as shown in the image above.

Selecting, deselecting and hiding layers

You can:

  1. Toggle layers on or off the map using the checkbox next to the name of the layer
  2. Each layer also provides options to zoom to the extent of the layer, get information on the layer and remove the layer. Removing the layer deletes it and it would need to be reapplied if required later.
  3. The Reset map button, reverts the map to its default state, all information is removed and must be reapplied if needed later.  you can use the Save button to keep a save the map setting for later use.

Changing the basemap

The Base map can be changed by selecting the appropriate radio button. The Outline map was designed for producing simple thumbnail images of the map. Streets provides a minimal base map, while the Open Street Map, Hybrid and Satellite make use of Google’s map services. One of the basemaps should be suitable for your application.

Changing the Map projection

This function is currently under construction and is available to test. To date best results are found using the Outline base layer.

Add WMS Layer

WMS stands for the OGC Web Map Services (WMS) standard. This standard allows for the display of images that are registered geographically from an external (or internal) service provider. The layers are images and not the data behind the images so these layers do not support all the functions of the ‘Add to Map | Layers’ stored in the Spatial Portal. These external layers are however very handy if they display information that may be useful for providing additional context. If you know, or can find a web address of a Web Map Service “Get Capabilities”, any layers they make available can be draped over the map. Examples of such services are provided to demonstrate this function.

Adding a base layer map via a WMS service

Three example WMS servers are given as all three have data layers that are very useful in the context of the Atlas:

Paste the URL of a WMS server, possibly one of the three examples above, into the WMS Server URL text field. Then press the “Select Layers” button. Assuming the web service URL is correct, a list of available layers will be seen in the dropdown box and one layer at a time can be added to the Spatial Portal.

The address of a single layer can also be cut and pasted into the WMS getMap URL field to add the layer. Any valid single WMS get layer request with the appropriate parameters can be used in the Atlas.

Using the WMS service to select a single layer

Selecting the load all layers WMS option, populates the Layers pulldown list, after pasting in a valid WMS server URL. You can select any single layer at a time from the service if the WMS “get capabilities” response lists more than one layer available.

Using the WMS service to select from all layers within a WMS service

This is the result of adding the Auscover Wirada: anra basins layer to the Spatial Portal-

Reset Map

This option is used to reset the spatial portal back to the default state – it removes all layers, switches to the normal base layer and zooms to show the Australian region.