groups-and-containers

Create a Group with a maxSize and classType, then call group.get(x, y) to fetch the first inactive member or create one. Recycle objects with killAndHide, which sets active and visible to false without removing them from the group.

A Group is a logical collection with no transform, ideal for pooling and physics. A Container is a display-list GameObject whose position, rotation, scale, and alpha are inherited by children, making it suited for composite UI but with per-frame matrix overhead.

Use a Layer when you only need render-order bucketing and shared alpha, blend mode, or mask without position, rotation, or scale. Layers are lightweight, but they cannot be nested inside Containers.

Physics bodies on Container children become offset when the Container is not positioned at (0,0), because body coordinates do not account for the parent's transform. Avoid attaching physics bodies to Container children; use physics Groups instead.

Containers have no implicit size, so input fails until you call container.setSize(width, height) to define a hit area before setInteractive. Without an explicit size, pointer events have no region to test against.

No, killAndHide only sets active=false and visible=false; the object remains in the Group for reuse. This is the intended pooling behavior, letting group.get() return the inactive member later.