Adds test/multiPlayerTest.tscn plus a driver that runs the kitchen flow
across two game instances: grab/drop, dirt station, sink washing, hob
cooking, counter combining and plating. Runs headless (run_mp_test.ps1),
in two visible windows (run_mp_test_windowed.ps1), or by hand with
keyboard controls (play_mp_test.ps1). 108 checks, exits non-zero on
failure.
After every step both peers snapshot every item's position and rendered
state and the server diffs them. Targeted assertions only look at the
thing a step touched, which misses desyncs elsewhere - that audit is
what caught the last bug below.
Bugs found and fixed:
- net_pickable: apply_held_state() only wrote `enabled` in its
non-authority branch, so once a client grabbed an item every other
peer set enabled=false and regaining authority never restored it. The
server could then never pick that item up again, and a station would
"snap" it (emitting has_picked_up, so a plate still got marked dirty)
while pick_up() bailed out on the disabled item - leaving the zone
holding an item with no grab driver.
- network_manager: station gating only happened in the spawn path, so
stations baked into a scene file kept running their snap zones on
clients and grabbed items straight out of the local hand. Added
gate_existing_stations().
- network_manager: despawn_item() only freed the server's copy. Items
baked into a scene aren't tracked by the MultiplayerSpawner, so
consuming one left a ghost on every client, which then blocked the
station it sat in and got grabbed instead of its replacement.
- network_manager: the snap-into-station decision read the server's own
copy of the item position, but the reliable release RPC routinely
overtakes the synchronizer's unordered position updates - so it acted
on a stale position and teleported items back into the station they
had just been carried away from. The releasing peer now sends its
final transform and the server adopts it first.
- container: contained_ids.append()/erase() mutate the array in place,
which never fires the setter that rebuilds the plate's visuals. The
peer that put food on a plate was the only peer that never redrew it;
remote peers looked right because the synchronizer assigns there.
Also null-guards XRServer.get_tracker() in the vendored xr-tools hand
grab point, which threw on every successful grab without an XR runtime,
and adds multiplayer_world.populate_from_layout so debug scenes can bake
their own content instead of spawning the whole kitchen.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
JonShard