RoweRC 0.1.5 - experimental car contact

Experimental car contact is available from the in-game F8 menu. Both players need 0.1.5. The host selects Toggle experimental car contact (host), then both players close F8 and enter Drive. Contact starts off in each new lobby.

• A convex footprint from the actual body mesh plus four tire cylinders follows body choice, wheel placement and steering.
• The host resolves relative contact speed, off-centre yaw and sliding friction. Each owner applies an acknowledged impulse to its native driving simulation.
• Upright heading interpolation is smoother, network packets omit duplicated bridge/debug data, and F8 shows Steam ping, arrival jitter and update cadence.
• Existing automatic updaters can fetch this release. Use F8's update check to request it immediately, then close and reopen the game after the update-ready notice.

This contact model follows the game's upright XY-plane physics. It uses a convex body outline, equal nominal 1.5 kg cars and geometry-derived yaw inertia; it does not provide 3D triangle contacts, deformation or tumbling. Latency can delay the visible response. Two-PC collisions and the latest subjective smoothing changes still need playtesting, especially across a UK connection.

Validation: 85 backend checks, 19 smoothing checks, 6 appearance checks, 8 native-adapter checks and six Lua parse checks passed. A local native fixture generated five collider shapes with 88 points, produced a 2,346-byte pose/dynamics packet, and applied and acknowledged a computed contact on the real car. The other car in that fixture was simulated, so this does not establish two-PC contact acceptance. The host's F8 toggle was also checked in the installed game.

Supported: Epic Windows RC Tandems build 3c46a39f90, Unreal 5.7. Steam transport continues to use development App ID 480.