Configuration of rendering point data¶
The Point element is defines the rendering of point data. A Layer with point data can contain one or more NetCDF variables (identified by Variable elements in the configuration file). If there are exactly two Variable elements the layer is assumed to contain wind speed and direction (see Vector).
There are many rendering possibilities for point data.
Point data can be rendered:
- as a text on the map on or around the station's location (single and multiple Variables) "point"
- as text on a coloured disc (one Variable): "disc"
- as a kind of fuzzy cloud: "volume"
- as a symbol determined by the point value and a set of SymbolInterval definitions: "symbol"
The plotstationid attribute (true/false) defines if the stationid is plotted together with the data.
Appearance of a text is determined by the textcolor, fontfile and fontsize attributes. The numeric value is formatted into a text by the printf-style format string of the textformat attribute. Tip, no text is rendered when textformat is set to a blank space (" ").
<Point fillcolor="" linecolor="" textcolor="" fontfile="" fontsize="" discradius="5" textradius="" textformat="%f" dot="false" anglestart="" anglestep="" plotstationid="true" pointstyle="point"></Point> <RenderMethod>point</RenderMethod>
This pointstyle draws a circle at the station location, coloured according to the value of the first variable of the layer and the Legend. If discradius is defined to be larger than 0 a circle is drawn at the station's location in a color determined by the data value and the Style's Legend.If discradius is 0 then the data's value is plotted centered at the station's location.
The attribute linecolor specifies a color for the edge of the circle. Making the linecolor transparent (linecolor="0x00000000") draws no line around the circle.
The value can be plotted next to the point. When 2 or more Variables are defined in a layer, the values get plotted in a circle around the station's location. The values are plotted starting at the angle defined by the anglestart attribute and are anglestep degrees apart. The distance of the text from the station's location is defined by the textradius attribute.
If a fillcolor attribute is specified the circle is drawn in the specified fixed color. A circle will be drawn around the disc in the linecolor.
The attribute dot plots a dot at the station's location; this can be useful during testing of the configuration of a point data style.
Single variable layer example:
Multiple variable layer example:
Pointstyle disc can only handle 1 variable in a layer or 2 in case of wind data (direction/speed).
The attribute discradius defines the size of the disc on which the value text is drawn, fillcolor defines the color of the disc (this color can contain transparency).
The attributes anglestart, anglestep, linecolor, plotstationid and textradius have no meaning here.
Example with temperature data:
Pointstyle volume shows a fuzzy disc at the station's location. This style is most useful for events that can occur often and overlap (because the rendered discs are translucent).
The base color of the disc is defined by the fillcolor attribute.
A station id is plotted if the plotstationid attribute has the value true.
The attributes anglestart, anglestep, linecolor and textradius have no meaning here.
When set to "symbol", it enables the SymbolInterval to draw Symbols/Icons on the map
When set to "zoomablepoint", the point keeps the same size across zooming and reprojections. This is used to plot IASI satellite imagery:
<Style name="IASI"> <Legend fixed="true" tickinterval=".1">temperature</Legend> <Min>0</Min> <Max>1</Max> <NameMapping name="point" title="IASI" abstract="IASI"/> <Point plotstationid="false" pointstyle="zoomablepoint" textformat=" " discradius="10" textradius="0" dot="false" fontsize="8" textcolor="#000000" /> <RenderMethod>point</RenderMethod> </Style>