Thematic Layer Configuration
Since Thematic Mapping is now available via OGC Layers the option to configure Thematic Layers has been deprecated from V5.6.0.
In Studio, choose the Map Source that relates to your MapServer map file, and create a new Thematic Layer in the appropriate Layer Group right click and select Add New Thematic Layer or click on an existing entry to change its details.
To remove a Thematic Layer from a Layer Group right click on the layer in the tree and select Delete Layer.
When adding or editing a Thematic layer the following Layer dialog will be displayed:
Layer Attributes
Display Name
This is description that is shown to the user and is a hyperlink Label name for the thematic layer. This entry must not be specified as a number only e.g. “Planning 1992” not “1992”
Layer Name
This is the actual Layer Name as defined in the .map file. Select a valid entry from the drop down list box.
You cannot specify the same Layer Name twice, if you do the subsequent entries will not be displayed.
Legend Image
This contains name of the name of the image file that is to be used in the legend control, in combination with the, previously defined, Display Name. If this is left blank then no image will be displayed.
This image file must reside in the Web/Legend/Images folder. In order to pick the legend image in Studio, it must also be present in the Web Service image folder [Web Service/Legend/Images], or you will get an error from Studio.
Info click
Select this check box if you wish to be able to perform a information click on this layer through the map.
Can Be Activated
This defines which layers can become “Active Layers”. The active layers will form the core of the services that can be shown.
If you do not check this entry then this layer will not be able to be turned on or off.
Visible on Startup
Check this entry if you wish the selected layer to be visible to the user when they first display the page.
Thematic Settings
The thematic settings are shown in the right-hand boxes of the main dialogue window. There are two types of thematic map available, Area (or polygon) and Point, and then three methods for classifying the data. These are described as follows:
Area
Polygon Mapping: This will display your polygons with a different colour depending on the value in the numeric totals column. The colour range is defined in Studio, along with the number of ranges or classifications that you require.
Point
Point Mapping: This will display points with symbols of a differing size dependent on the value in the numeric totals column. The type of symbol, colour, and size range are defined in Studio, along with the number of ranges or classifications that you require.
Auto
This box should normally be ticked - this will choose point or polygon mapping dependent on the setup in your MapServer .map file. Un-ticking the box will allow you to override the MapServer configuration, for example to display your polygon data as point.
Method
Equal Count: This will classify your data such that for each range of data, there are an equal number of records (or rows in the table). Ranges will not be of equal size.
Equal Range: This will classify your data such that the ranges are of equal size. There will not necessarily be an equal number of records in each range.
Standard Deviation: This places ranges at various standard deviations either side of the mean value of your data. Ranges will not necessarily be the same size, or contain the same number of records.
Number of Ranges
Select the number of Ranges you wish for your Thematic Layer
Start Colour
Choose the colour you wish for the Start of your range.
End Colour
Choose the colour you wish for the End of your range.