Hand contacts

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Motorcycle hand contacts

The motorcycle uses the same IK Edit rig system as every other creation. The driver and compatible observing viewers receive definitions and solve them locally for the rider's own shape and animation. Ordinary viewers continue displaying the underlying animation.

Install and calibrate

1. Name the target links Left and Right, with one of each name.
2. In Build > IK Edit > Bindings, select each wrist, bind it to its grip, and position/rotate the bone to author its target-relative offsets.
3. Click Copy complete IK script and replace the contact companion's entire source in the motorcycle root. Keep the vehicle's main script. motorcycle-hand-ik.lsl provides a starting configuration; the editor export contains your calibration.
4. Keep EXTERNAL_CONTROL = TRUE and have the main script respond to sync on channel -190018108 with its current profile or off.

The starting motorcycle declaration contains drive (both wrists) and gas_only (right wrist). Both reuse the same binding data; changing profile does not duplicate offsets or restart a contact that is common to both.

The viewer automatically installs a separate #Aurora Bridge IK script. On region arrival it asks, once, the objects avatars sit on and your own attachments, each one directly, never the whole region; other avatars' worn publishers show at their next announcement. The motorcycle announces as soon as somebody sits and returns its definition even before the engine's IK profile is enabled. Full definitions are sent only to a requesting bridge; state changes are small regional events. There is no periodic observer search or 25-second renewal in live sessions. Replace the complete motorcycle companion with a new export for this transport, preserving the calibrated RIG. The main script's profile commands stay the same. To recover an editor project without sitting, choose Create a new IK project > From an object or attachment and click the motorcycle. The current companion answers that explicit request even while unused; the viewer creates a separate project without changing the motorcycle's active profile. Existing companions need the updated source for this authoring request.

// Ready and riding:
llMessageLinked(LINK_THIS, -190018108, "profile drive", NULL_KEY);
// After choosing a one-handed pose:
llMessageLinked(LINK_THIS, -190018108, "profile gas_only", NULL_KEY);
// End of the round:
llMessageLinked(LINK_THIS, -190018108, "off", NULL_KEY);

The main script chooses its IK mode independently of any animation. It does not look up animation asset UUIDs or require animation inventory permissions. On drive -> gas_only, the left hand fades out and the right hand stays attached. On return, only the left hand begins fresh entry conditions. A source counter per binding also covers intermediate switches missed by an observer. Repeating the same keyword retains current contacts. A complete off/on starts a fresh global lifetime. Static data remains cached across modes. Use EXTERNAL_CONTROL = FALSE only to start the first profile automatically while seated/worn. IK Edit itself stays independent of these commands.

Keep the main script's llStartAnimation("accel_F") at the existing throttle event. All viewers receive exactly the same animations. Block applies IK after normal animation blending; no fallback animation is filtered or stopped. Rotate Right at that same event so its bound wrist follows the moving grip. motorcycle-throttle.lsl can consume the existing engine tap/stop messages on channel 17001. Use it only if the main script does not already embed the throttle helpers. It applies an absolute local rotation from a saved rest pose, pulses for 0.46 seconds, and restores the rest pose on stop or reset. THROTTLE_DEGREES controls the angle; zero THROTTLE_AXIS selects the longest local prim axis. A helper prim may need an explicit axis. The rest rotation is stored per prim UUID in linkset data; remove its aurora.throttle.rest.<UUID> entry before a reset if intentionally recalibrating the grip's neutral rotation.

Offsets are metric in the target prim's axes; prim scale does not resize them. The optional contact point is bone-local before avatar hand scaling. Zero targets the wrist pivot. Follow rotation uses the calibrated quaternion; position-only follows the grip while retaining animated wrist articulation. The solve respects shaped/mesh-overridden bone lengths and can use the selected chain root for torso assistance. Finger closure remains animated.

Standing, losing/deleting the source, detaching, teleporting, region changes and logout release the applicable sessions without a final off message. Unused creations cannot populate a rig catalog: only occupied seats and worn attachments are queried, with definitions held temporarily during that use. Each definition is limited to 8 KiB; aggregate data, including partial transfers, is limited to 32 KiB per avatar and 128 KiB for the current region. Inactive announcements, unsolicited data and excess traffic are discarded. Leaving the seat, removing the source or relay and changing region drop negotiated data. The shared protocol contract describes event discovery, nonce/revision validation and the limits of detecting a silent stopped script without polling. There is one supported wire protocol, auroraIK/5.

Offline checks use AURORA_DEMO_HAND_IK=1|moving|release|observer|observer-release. Real LSL compilation and two-viewer motorcycle behaviour require human validation; agents never connect to a grid.