Gameable Engine

Add a locomotion state ​

Goal ​

Play authored rise, fall and landing clips using the shared third-person controller. The character bundle must already contain the six named clips below. Ground contact comes from physics, so reaching the jump apex cannot trigger a landing animation.

Files you will edit ​

  • src/systems/locomotion.ts
  • src/game.ts

Steps ​

  1. Select the clips. Replace the existing controller construction in src/systems/locomotion.ts, keeping its reset/update exports and dialogue gate:

    ts
    const controller = createThirdPersonController({
  idle: 'idle',
  walk: 'walk',
  run: 'run',
  rise: 'jump-rise',
  fall: 'jump-fall',
  land: 'jump-land',
});

    Names refer to clips in the character's loaded bundle, not asset paths. Configure jump clips as non-looping in the bundle. Explicit clip weights select the performance; a character.setState label alone does not select a clip.

  2. Tune launch and landing. Add these values to rules in src/game.ts:

    ts
    jumpSpeed: 6,
jumpLockFrames: 3,
landingSeconds: 0.18,
acceleration: 10,
deceleration: 14,

    Gravity remains a world/host physics setting. Set both consistently when changing it. The host drives the capsule trajectory; prepared clips should have stationary horizontal root motion. The controller preallocates its weights and never adds frame allocations.

  3. Understand the transitions. The controller reads ctx.physics.isGrounded(hero) from the preceding physics step. Launch selects rise, negative vertical speed selects fall, and walkable ground contact selects landing for landingSeconds. Jumping again during landing starts rise immediately. Without a clip mapping the controller still sends semantic states and uses the default locomotion blend.

Verify ​

sh
npm test -w templates/third-person
npm run dev -w templates/third-person

Jump twice, walk off a ledge, and press jump at the apex. The apex must remain airborne, the second grounded jump must replay, and walking/running must resume after landing. Check both direct and compiled WASM builds after changing packages.

See also ​