FireNoise.xml

<sequence values="BGOERK">
  <prl steps="75">
    <rule in="OG" out="*O"/>
    <rule in="O*/*G" out="**/*O"/>
    <rule in="B" out="G" p="0.01"/>
    <rule in="O" out="B"/>
    <rule in="G" out="O" p="0.0001"/>
  </prl>
  <all in="*G*/GBG" out="***/*G*"/>
  <all>
    <rule in="*B*/BGB/*B*" out="***/*B*/***"/>
    <rule in="*BB*/BGGB/*BB*" out="****/*BB*/****"/>
  </all>
  <markov>
    <sequence>
      <one in="G" out="R" steps="1"/>
      <all in="RG" out="RR" steps="10"/>
      <all in="RG" out="EE"/>
      <all>
        <rule in="ER" out="*E"/>
        <rule in="EG" out="*E"/>
      </all>
    </sequence>
  </markov>
  <markov>
    <sequence>
      <one in="B" out="K" steps="1"/>
      <all in="KB" out="*K" steps="10"/>
      <all in="KB" out="GG"/>
      <all>
        <rule in="GB" out="*G"/>
        <rule in="GK" out="*G"/>
      </all>
    </sequence>
  </markov>
  <prl>
    <rule in="K" out="E"/>
    <rule in="G" out="B"/>
  </prl>
</sequence>

<!--
A noise-like generator based on the forest-fire model https://en.wikipedia.org/wiki/Forest-fire_model
-->