Mark WKT Plugin
---------------

This plugin adds the rendering of marks built from WKT geometries; moreover, it adds some Java-generated shapes that are used to draw meteorological symbols... hope the weathermen will find this useful.

WKT Marks
^^^^^^^^^

The use of WKT marks (prefiex with "wkt://" in your SLD) allows an easy way to add complex symbols to the rendering process.

Examples:

* A double dashed line with transparent background can be shown with this SLD fragment::

          <LineSymbolizer>
            <Stroke>
              <GraphicStroke>
                <Graphic>
                  <Mark>
                    <WellKnownName>wkt://MULTILINESTRING((-0.25 -0.25, -0.125 -0.25), (0.125 -0.25, 0.25 -0.25), (-0.25 0.25, -0.125 0.25), (0.125 0.25, 0.25 0.25))</WellKnownName>
                    <Fill>
                      <CssParameter name="fill">#0000ff</CssParameter>
                    </Fill>
                    <Stroke>
                      <CssParameter name="stroke">#0000ff</CssParameter>
                      <CssParameter name="stroke-width">1</CssParameter>
                    </Stroke>
                  </Mark>
                  <Size>6</Size>
                </Graphic>
              </GraphicStroke>
            </Stroke>
          </LineSymbolizer>
  
  Which gives this output: 
  
  
  .. image:: /images/double-dashed-line.png

* This module supports curves as well; for instance, this SLD fragment::
  
          <LineSymbolizer>
            <Stroke>
              <GraphicStroke>
                <Graphic>
                  <Mark>
                    <WellKnownName>wkt://COMPOUNDCURVE((0 0, 0.25 0), CIRCULARSTRING(0.25 0, 0.5 0.5, 0.75 0), (0.75 0, 1 0))</WellKnownName>
                    <Fill>
                      <CssParameter name="fill">#0000ff</CssParameter>
                    </Fill>
                    <Stroke>
                      <CssParameter name="stroke">#0000ff</CssParameter>
                      <CssParameter name="stroke-width">1</CssParameter>
                    </Stroke>
                  </Mark>
                  <Size>10</Size>
                </Graphic>
              </GraphicStroke>
            </Stroke>
          </LineSymbolizer>
  
  Produces this:
  
  .. image:: /images/emicircle-line.png

Property File Configuration
^^^^^^^^^^^^^^^^^^^^^^^^^^^

WKT shapes may be pooled in properties files (this file must be packed in the same JAR of this module) and re-used across SLD files, becoming libraries of symbols.

For instance the WKT marks defined in this properties files (wkt.properties)::
  
  ls=LINESTRING(0.0 0.25, 0.25 0.25, 0.5 0.75, 0.75 0.25, 1.00 0.25)
  ...


To reference the above property file in your SLD, prefixed like this (note the protocol changed to "wktlib://")::
  
  <WellKnownName>wktlib://wkt.properties#ls</WellKnownName>

The location of the property file is either to be provided as an absolute path, or should be relative to a search root which can be programmatically set using ``WKTMarkFactory.setRoot(URL)``
  
Weather symbols
^^^^^^^^^^^^^^^

The weather symbols, which are create using Java code, should be prefixed by the "extshape://" protocol in the SLD,  are, for the time being, limited to the following

* Triangle::
     
     <WellKnownName>extshape://triangle</WellKnownName> 
  
  Produces:
  
  .. image:: /images/triangle.png
* Emicircle::
    
     <WellKnownName>extshape://emicircle</WellKnownName> 
   
  Produces:
  
  .. image:: /images/emicircle.png
* Triangle Emicircle::
     
     <WellKnownName>extshape://triangleemicircle</WellKnownName> 
  
  Produces:
  
  .. image:: /images/triangleemicircle.png