data/test/user/testdata/hfield_xml.xml

<mujoco>
  <asset>
    <hfield name="J" size="0.9 1.1 .2 .1" nrow="12" ncol="10" elevation="
            0 0 0 0 0 0 0 0 0 0
            0 0 0 0 0 0 0 0 0 0
            0 0 0 0 0 0 1 1 0 0
            0 0 0 0 0 0 1 1 0 0
            0 0 0 0 0 0 1 1 0 0
            0 0 0 0 0 0 1 1 0 0
            0 0 0 0 0 0 1 1 0 0
            0 0 1 1 0 0 1 1 0 0
            0 0 1 1 1 1 1 1 0 0
            0 0 1 1 1 1 1 0 0 0
            0 0 0 0 0 0 0 0 0 0
            0 0 0 0 0 0 0 0 0 0"/>
  </asset>

  <worldbody>
    <light pos="0 0 1"/>
    <geom type="hfield" hfield="J"/>
  </worldbody>
</mujoco>