Squashed 'particlemap/' content from commit d18bd10

git-subtree-dir: particlemap
git-subtree-split: d18bd101fb69d1f4641ad6ccc38d91335a046fb0
Merge commit '6125e660b62e7d475507889c9a28b82a5465d79d' as 'particlemap'
git is tricky