OptionalisPredicate for "this object is a nesting parent body". The leaf scan skips objects for which this returns true so a click on a parent's painted body resolves to a child leaf, not the parent itself. Default: never (treat every object as hittable).
OptionalposeDerive an axis-aligned bounding rect from a (world-space) pose. Default
reads x / y / width / height straight off the pose (matches
RectPose). Override for non-rect poses (e.g. paths).
Compose a child's local pose into world coords given its parent's world pose. Same shape as
composeRectPose(the default expectation).