mujoco

<mujoco>
  <option>
    <flag multiccd="enable"/>
  </option>

  <visual>
    <scale forcewidth="0.01" contactwidth="0.05" contactheight="0.05"/>
    <map force="0.1"/>
  </visual>

  <asset>
    <mesh name="die" file="die.obj" scale=".02 .02 .02"/>
  </asset>

  <default>
    <geom condim="1" type="mesh" solref="2e-5 1"/>
    <default class="wall">
      <geom type="box" rgba="0.1 0.2 1 .2"/>
    </default>
    <default class="floor">
      <geom type="box" rgba="0.1 0.2 1 1"/>
    </default>
  </default>

  <worldbody>
    <light pos="0 0 1" dir="0 0 -1" castshadow="false"/>
     <body name="container" pos="0 0 -0.11">
      <geom class="floor" size="0.27 0.27 0.01"/>
      <geom class="wall"  size="0.26 0.01 0.10" pos="0.01 0.26 0.11"/>
      <geom class="wall"  size="0.26 0.01 0.10" pos="-0.01 -0.26 0.11"/>
      <geom class="wall"  size="0.01 0.26 0.10" pos="0.26 -0.01 0.11"/>
      <geom class="wall"  size="0.01 0.26 0.10" pos="-0.26 0.01 0.11"/>
    </body>

    <replicate count="5" offset=".1 0 0">
      <replicate count="5" offset="0 .1 0">
        <replicate count="4" offset="0 0 .1">
          <body pos="-.2 -.2 0.15">
            <freejoint/>
            <geom type="mesh" mesh="die"/>
          </body>
        </replicate>
      </replicate>
    </replicate>
  </worldbody>
</mujoco>