Alder court is an early shared driving scene: an original cedar deck with iron rims, brass wheel hubs and a bow marker, on a sunlit stone courtyard. One traveler controls the cart from a reserved driver seat while another rides in a passenger seat. It uses the existing room-owned body, pilot reservation and rider recovery paths.
#Try it
Run npm run dev:editor and open the private editor URL printed by the command.
Choose New world → Alder court, Use this world, Save, then Apply.
Open the shared playtest in two separate browser profiles or a private window.
Arrival starts on the deck. Press E to claim the first free seat; seat 1 is the driver and seat 2 is the passenger. The driver uses W/S to drive or reverse and A/D while moving to steer. Press E again to stand up, or Space to jump off. Seated passengers look around but cannot move or steer. The camera follows the cart’s turning while preserving your ability to look around. If two travelers arrive at exactly the same position, have the passenger step sideways; arrival spacing remains a review item. Reloading retains the seat reservation and restores the saved moving support, without replaying a held throttle.
Select alder-cart → Floating physics to tune the saved vehicle. Drive on → Ground · cart enables suspension travel and tire grip. The common speed, acceleration and turning controls remain available. Save/Undo/Redo and shared Apply use the regular document transaction. A ground vehicle needs a flat deck at least 1.2 m wide and long, no thicker than 0.6 m. Water is not required.
Add reserved seats and mounted cameras enables one to four local seat positions and a saved eye height. Keep seats at least 0.7 m apart and 0.3 m inside the deck edge. The first seat always controls the vehicle. Seat settings also work with the existing raft profile. Changing seat placement releases reservations; ordinary speed/grip edits preserve them. The editor changes the mount positions, not the model geometry: fit imported seat artwork separately.
For a fresh PostgreSQL/Coolify room, use DW_ROOM_TEMPLATE=cart with the
existing persistent Docker setup. DW_ROOM_AUTHORITY=cooperative or trusted
selects the authority profile. An existing database room retains its pinned
release; changing the template variable does not replace that world. No live
production deployment was performed for this increment.
#Implementation and bounds
World format 32, compiler vehicle-world.32, introduced the cart.1 drive
profile inside the common body driver settings. Older raft worlds retain their
existing profile and compiler identity. New authored settings are speed 0.5–4 m/s,
acceleration 0.25–3 m/s², front steering angle 0.1–1 radians, suspension travel
0.1–0.4 m and tire grip 0.1–1. The existing shared control field is still called
raftInput internally; it carries bounded throttle and steering, never client
forces or velocities.
Format 33, compiler vehicle-seats-world.33, adds optional vehicle-seats.1
settings and floating-room.6 occupancy snapshots. Presentation format 18 carries
seated poses while older envelopes keep their existing restrictions. Driver and passenger leases
recover together, with at most eight occupied seats/helms across the room. A
blocked mounting sweep rejects entry; jumping or leaving the deck releases the
seat. The character keeps its upright capsule for collision. The lowered camera
and bent-leg pose are presentation, not a shorter seated collision shape. Cedar
seat artwork may extend up to 1.1 m above the chassis.
Four fixed 0.2 m wheel probes cast down from the chassis. Springs and damping support the chassis; tire impulses are limited by load and grip. The front pair steers, and neutral input adds rolling resistance. Traction requires a supporting surface no steeper than 45 degrees and an upright chassis. Probes ignore sensors, dynamic bodies and the chassis itself. Suspended carts currently support driving on static ground and kinematic platforms; tires do not climb other dynamic bodies. The chassis still collides as a box and uses continuous collision detection.
Suspension/contact values derive from the current native frame; no hidden wheel integrator or input state needs recovery. Saved native motion, body identity, pilot reservations and rider support use the existing floating/cargo snapshots. The compiler permits cart artwork to extend below the chassis only within its maximum supported suspension/wheel envelope. Other dynamic models retain their unit-box bounds. Wheel artwork is currently static relative to the chassis.
#Focused acceptance and deferred review
- Ground-vehicle, neighboring raft and actor-motion checks pass. Six seat checks cover conflicting reservations, independent release, mounted position/camera, seated rig attachments, legacy-helm live edits, shared state projection and the seated presentation wire format. The wire regression fixes an observed passenger disconnect when a seated pose was sent using an older presentation envelope.
- Two PostgreSQL checks pass: cooperative/trusted cart frames, driver and passenger seats survive replacement ownership, reject the retired writer and continue exactly.
- The software-WebGPU browser journey covers gallery creation, saved speed/grip, Undo/Redo, shared Apply, Worker/main-thread players, driving/steering with a seated passenger and driver reload. Client and immutable engine packaging succeed.
- Type/import checks pass. Editor, controls and player captures are visually reviewed; this is an early functional vehicle, not final art approval.
Return for wheel spin, visible steering/suspension animation, adjustable wheel placement and a fuller vehicle appearance. Review seat entry/exit transitions, feet/seat contact, camera comfort and obstruction behavior before final release. Also retain shared arrival spacing, seat UI on narrow displays and near-camera traveler occlusion for the final character pass. Physical/mobile GPUs, rough terrain and slopes, high-speed impacts, larger passenger counts, sustained memory/frame time, control-loss cases, trusted browser replay, cart cargo crossings and separate-owner handoff still need qualification. The existing native/room restart checks do not prove that broader matrix. The owned physics backend, ragdolls and other advanced traversal remain open in the full plan. Final character/environment/arrival art is required and unapproved.