mapnik/tests/data/good_maps/shield_symbolizer.xml

<!DOCTYPE Map>
<Map background-color="#b5d0d0" srs="+init=epsg:4326" minimum-version="0.7.0">
    <Style name="1">
        <Rule>
            <ShieldSymbolizer name="[label]" file="../images/dummy.png" size="10" transform="scale(5) translate(15, 15) rotate(20) skewX(20) skewY(5)" dy="-5" dx="-5" opacity=".5" text-opacity=".3" face-name="DejaVu Sans Book" halo-radius="1" shield-dx="10" shield-dy="10" no-text="false" allow-overlap="true" avoid-edges="false"/>
        </Rule>
        <Rule>
            <PointSymbolizer allow-overlap="true"/>
        </Rule>
    </Style>
    <Style name="2">
        <Rule>
            <LineSymbolizer/>
        </Rule>
        <Rule>
            <ShieldSymbolizer name="[label]" file="../svg/ellipses.svg" size="10" opacity=".5" text-opacity=".3" spacing="50" placement="line" allow-overlap="true" face-name="DejaVu Sans Book" no-text="false" line-spacing="10"/>
        </Rule>
    </Style>

    <Layer name="line" srs="+init=epsg:4326">
        <StyleName>2</StyleName>
        <Datasource>
            <Parameter name="file">../json/lines.json</Parameter>
            <Parameter name="layer_by_index">0</Parameter>
            <Parameter name="type">ogr</Parameter>
        </Datasource>
    </Layer>

    <Layer name="point" srs="+init=epsg:4326">
        <StyleName>1</StyleName>
        <Datasource>
            <Parameter name="file">../json/points.json</Parameter>
            <Parameter name="layer_by_index">0</Parameter>
            <Parameter name="type">ogr</Parameter>
        </Datasource>
    </Layer>

</Map>