mapnik/tests/visual_tests/styles/halo-comp-op-on-satellite.xml

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE Map[]>
<Map srs="+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs">
  <Parameters>
    <Parameter name="sizes">450,450</Parameter>
  </Parameters>

<Style name="raster">
  <Rule>
    <RasterSymbolizer opacity="1" scaling="bilinear" comp-op="src-over"/>
  </Rule>
</Style>
<Layer name="raster"
  srs="+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs">
    <StyleName>raster</StyleName>
    <Datasource>
       <Parameter name="file">../data/satellite.png</Parameter>
       <Parameter name="extent">0,0,10,10</Parameter>
       <Parameter name="type">gdal</Parameter>
    </Datasource>
</Layer>

<Style name="labels">
  <Rule>
    <Filter>[x]=2</Filter>
    <TextSymbolizer
      face-name="DejaVu Sans Book"
      size="15"
      halo-opacity=".1"
      halo-radius="2"
      halo-rasterizer="fast"
      fill="#03080D"
      halo-comp-op="difference"
      >
      'M a p n i k'
    </TextSymbolizer>
  </Rule>
  <Rule>
    <Filter>[x]=5</Filter>
    <TextSymbolizer
      face-name="DejaVu Sans Book"
      size="15"
      halo-fill="gray"
      halo-opacity=".2"
      halo-radius="2"
      fill="#29471B"
      halo-comp-op="invert-rgb"
      >
      'M a p n i k'
    </TextSymbolizer>
  </Rule>
  <Rule>
    <Filter>[x]=8</Filter>
    <TextSymbolizer
      face-name="DejaVu Sans Book"
      size="15"
      halo-fill="gray"
      halo-opacity=".3"
      halo-radius="1"
      fill="#F6EDB7"
      halo-comp-op="invert"
      >
      'M a p n i k'
    </TextSymbolizer>
  </Rule>
</Style>

<Layer name="labels" srs="+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs">
    <StyleName>labels</StyleName>
    <Datasource>
        <Parameter name="inline">x,y
2,1
2,2
2,3
2,4
2,5
2,6
2,7
2,8
2,9
5,1
5,2
5,3
5,4
5,5
5,6
5,7
5,8
5,9
8,1
8,2
8,3
8,4
8,5
8,8
8,6
8,7
8,8
8,9
</Parameter>
        <Parameter name="type">csv</Parameter>
    </Datasource>
</Layer>

</Map>