The centre angle (radians, in the parent's reference plane) a co-orbital
belt population — e.g. Jupiter's Trojans — should cluster around at a
given time: its reference body's current angle around the belt's own
parent, plus the fixed lead/trail offset (+60°/-60° for L4/L5). Returns 0
for a belt with no coOrbital set, or if the reference body can't be
found (falls back to spreading around the whole circle rather than
silently collapsing to a single point).
Pass positions — this frame's resolveAllPositions result — when one is
already to hand, to read both bodies' positions from it instead of
re-walking their parent chains.
The centre angle (radians, in the parent's reference plane) a co-orbital belt population — e.g. Jupiter's Trojans — should cluster around at a given time: its reference body's current angle around the belt's own parent, plus the fixed lead/trail offset (+60°/-60° for L4/L5). Returns 0 for a belt with no
coOrbitalset, or if the reference body can't be found (falls back to spreading around the whole circle rather than silently collapsing to a single point).Pass
positions— this frame's resolveAllPositions result — when one is already to hand, to read both bodies' positions from it instead of re-walking their parent chains.