Workers
Worker 0
deque
Worker 1
deque
Worker 2
deque
Work Queue
Depth 0
(roots)
C0
C1
C2
parallel
barrier / wait
Depth 1
C3
C4
C5
C6
parallel
barrier / wait
Depth 2
C7
C8
C9
C10
C11
parallel
barrier / wait
Depth 3
C12
C13
parallel
↓
↓
↓
↓
All clusters within a depth run in parallel. A barrier ensures the next depth
only starts once all parent transforms are computed.