World coordinates describe positions and directions in the shared reference frame of a scene.
One frame for the whole composition
A gallery installation may contain a sculpture, a caption and a light. Each can have its own local coordinates, but their final placement can be expressed in the same world frame. This makes it possible to compare their locations even when they belong to different groups. A child object’s world position includes the effects of its parents’ transforms.
World space is not automatically a map of Earth
The word “world” can sound more permanent than it is. In an AR session, the reference frame may be established when tracking starts and may be adjusted as tracking improves. A world position is not necessarily a GPS location, a surveyed measurement or a position another visitor’s phone already understands. Shared placement and return visits need additional mechanisms.
A useful diagnostic
If an object appears in the wrong place, ask whether the intended offset was measured from the artwork, its parent or the scene origin. For a Painta project, this distinction is especially useful while preparing a multi-part 3D asset before import. Resetting one child’s local position can put it at its parent’s origin, not at the centre of the visible room.