mapnik_population.xml

<!DOCTYPE Map>
<!-- Sample Mapnik XML template by Dane Springmeyer -->
<Map srs="+proj=latlong +datum=WGS84" background-color="white" minimum-version="0.7.2">
  <Style name="population">
     <!-- Built from Seven Class sequential YIGnBu from www.colorbrewer.org -->
     <!-- Quantile breaks originally from QGIS layer classification -->
     <Rule>
      <Filter>[POP2005] &gt; -1 and [POP2005] &lt; 15000</Filter>
      <PolygonSymbolizer fill="#c7e9b4"/>
      <LineSymbolizer stroke="black" stroke-width=".1"/>
     </Rule>

     <Rule>
      <Filter>[POP2005] &gt;= 15000 and [POP2005] &lt; 255000</Filter>
      <PolygonSymbolizer fill="#7fcdbb"/>
      <LineSymbolizer stroke="black" stroke-width=".1"/>
     </Rule>

     <Rule>
      <Filter>[POP2005] &gt;= 255000 and [POP2005] &lt; 1300000</Filter>
      <PolygonSymbolizer fill="#1d91c0"/>
     </Rule>

     <Rule>
      <Filter>[POP2005] &gt;= 1300000 and [POP2005] &lt; 4320000</Filter>
      <PolygonSymbolizer fill="#41b6c3"/>
     </Rule>

     <Rule>
      <Filter>[POP2005] &gt;= 4320000 and [POP2005] &lt; 9450000</Filter>
      <PolygonSymbolizer fill="#225ea8"/>
     </Rule>

     <Rule>
      <Filter>[POP2005] &gt;= 9450000 and [POP2005] &lt; 25650000</Filter>
      <PolygonSymbolizer fill="#225ea8"/>
     </Rule>

     <Rule>
      <Filter>[POP2005] &gt;= 25650000 and [POP2005] &lt; 1134000000</Filter>
      <PolygonSymbolizer fill="#122F7F"/>
     </Rule>

     <Rule>
      <ElseFilter/>
      <!-- This will catch all other values - in this case just India and China -->
      <!-- A dark red polygon fill and black outline is used here to highlight these two countries -->
      <PolygonSymbolizer fill="darkred"/>
      <LineSymbolizer stroke="black" stroke-width=".7"/>
     </Rule>

   </Style>

   <Style name="countries_label">
     <Rule>
      <!--  Only label those countries with over 9 Million People -->
      <!--  Note: Halo and Fill are reversed to try to make them subtle -->
      <Filter>[POP2005] &gt;= 4320000 and [POP2005] &lt; 9450000</Filter>
      <TextSymbolizer size="7" fill="black" face-name="DejaVu Sans Bold" halo-fill="#DFDBE3" halo-radius="1" wrap-width="20">[NAME]</TextSymbolizer>
     </Rule>

     <Rule>
      <!--  Only label those countries with over 9 Million People -->
      <!--  Note: Halo and Fill are reversed to try to make them subtle -->
      <Filter>[POP2005] &gt;= 9450000 and [POP2005] &lt; 25650000</Filter>
      <TextSymbolizer size="9" fill="black" face-name="DejaVu Sans Book" halo-fill="#DFDBE3" halo-radius="1" wrap-width="20">[NAME]</TextSymbolizer>
     </Rule>

     <Rule>
      <!--  Those with over 25 Million get larger labels -->
      <Filter>[POP2005] &gt;= 25650000 and [POP2005] &lt; 1134000000</Filter>
      <TextSymbolizer size="12" fill="white" face-name="DejaVu Sans Book" halo-fill="#2E2F39" halo-radius="1" wrap-width="20">[NAME]</TextSymbolizer>
     </Rule>

     <Rule>
      <!--  Those with over 25 Million get larger labels -->
      <!--  Note: allow_overlap is true here to allow India/China to sneak through -->
      <Filter>[POP2005] &gt;= 1134000000</Filter>
      <TextSymbolizer size="15" fill="white" face-name="DejaVu Sans Book" halo-fill="black" halo-radius="1" wrap-width="20" allow-overlap="true" avoid-edges="true">[NAME]</TextSymbolizer>
     </Rule>
  </Style>

  <Layer name="countries" srs="+proj=latlong +datum=WGS84" status="on">
    <!-- Style order determines layering hierarchy -->
    <!-- Labels go on top so they are listed second -->
    <StyleName>population</StyleName>
    <StyleName>countries_label</StyleName>
    <Datasource>
      <Parameter name="type">shape</Parameter>
      <Parameter name="file">data/world_borders/TM_WORLD_BORDERS-0.3.shp</Parameter>
    </Datasource>
  </Layer>
</Map>