mujoco

<mujoco>
  <compiler meshdir="asset" texturedir="asset"/>

  <statistic meansize=".05"/>

  <visual>
    <rgba haze="0.15 0.25 0.35 1"/>
    <quality shadowsize="4096"/>
    <map stiffness="700" shadowscale="0.5" fogstart="1" fogend="15" zfar="40" haze="1"/>
  </visual>

  <asset>
    <texture type="skybox" builtin="gradient" rgb1="0.3 0.5 0.7" rgb2="0 0 0" width="512" height="512"/>
    <texture name="texplane" type="2d" builtin="checker" rgb1=".2 .3 .4" rgb2=".1 0.15 0.2"
      width="512" height="512" mark="cross" markrgb=".8 .8 .8"/>

    <material name="matplane" reflectance="0.3" texture="texplane" texrepeat="10 10" texuniform="true"/>
  </asset>

  <worldbody>
    <light diffuse=".4 .4 .4" specular="0.1 0.1 0.1" pos="0 0 2.0" dir="0 0 -1" castshadow="false"/>
    <light directional="true" diffuse=".8 .8 .8" specular="0.2 0.2 0.2" pos="0 0 4" dir="0 0 -1"/>

    <geom name="ground" type="plane" size="0 0 1" pos="0 0 0" quat="1 0 0 0" material="matplane" condim="1"/>
  </worldbody>
</mujoco>