tilt/test/puck.mjs

import * as THREE from 'three';
import { createPhysicsWorld, initPhysics } from '../src/physics/world.js';
import { PUCK, createPuck } from '../src/physics/puck.js';
import { createMatch } from '../src/game/match.js';
import { CARRY } from '../src/game/possession.js';
import { RINK, insideRink } from '../shared/rink.js';
import { done, near, ok, section } from './harness.mjs';

/**
 * Puck, stick and possession.
 *
 * The two things worth testing hard are the ones that are hard to see: that a
 * 45 m/s shot does not tunnel through the boards (it moves ten times its own
 * radius per step, so it will unless it is a bullet), and that possession
 * behaves sanely at both ends of the magnetism dial — because that dial is a
 * feel decision that has not been made yet, and the code has to survive
 * wherever it lands.
 */

const DT = 1 / 60;
await initPhysics();

function arena(perTeam = 1) {
  const physics = createPhysicsWorld();
  const match = createMatch({ scene: new THREE.Group(), physics, perTeam, teams: 2 });
  return { physics, match };
}

/** Park everyone far from the play so they cannot interfere. */
function clearIce(match, keep = []) {
  for (let i = 0; i < match.states.length; i++) {
    if (keep.includes(i)) continue;
    const x = -RINK.halfX * 0.8 + i * 3;
    match.states[i].x = x;
    match.states[i].z = -RINK.halfZ * 0.75;
    match.states[i].vx = 0;
    match.states[i].vz = 0;
    match.skaters[i].proxy.teleport(x, -RINK.halfZ * 0.75);
    match.setControl(i, { x: 0, y: 0, sprint: false, brake: false, cameraYaw: 0 });
  }
}

section('the puck is a regulation puck');
{
  const physics = createPhysicsWorld();
  const puck = createPuck(physics);
  near(PUCK.radius * 2, 0.0762, 1e-4, 'three inches across');
  near(PUCK.thickness, 0.0254, 1e-4, 'one inch thick');
  near(puck.mass, 0.170, 0.005, `and 170 grams (got ${puck.mass.toFixed(3)} kg)`);
  puck.destroy();
  physics.destroy();
}

section('the puck settles flat on the ice and stays there');
{
  const physics = createPhysicsWorld();
  const puck = createPuck(physics, { position: { x: 0, y: 1.5, z: 0 } });
  for (let n = 0; n < 3 / DT; n++) physics.step(DT);
  const p = puck.position();
  ok(p.y > 0 && p.y < 0.05, `it lands on the surface (y=${p.y.toFixed(4)})`);
  // Angular X and Z are locked, so it can never be standing on its edge.
  const q = puck.rotation();
  const up = new THREE.Vector3(0, 1, 0).applyQuaternion(q);
  ok(up.y > 0.999, `and lies flat rather than rolling on its edge (up.y=${up.y.toFixed(4)})`);
  puck.destroy();
  physics.destroy();
}

section('a hard shot does not tunnel through the boards');
{
  // The headline risk. At 45 m/s the puck covers 0.37 m per 1/120 s step,
  // roughly ten times its own radius, so without continuous collision it goes
  // straight through the wall and is never seen again.
  for (const speed of [20, 45, 55]) {
    const physics = createPhysicsWorld();
    const puck = createPuck(physics, { position: { x: 0, y: 0.02, z: 0 } });
    puck.setVelocity(speed, 0, 0);
    for (let n = 0; n < 4 / DT; n++) physics.step(DT);
    const p = puck.position();
    ok(
      insideRink(p.x, p.z, 0),
      `a ${speed} m/s shot stayed in the rink (ended at x=${p.x.toFixed(2)}, z=${p.z.toFixed(2)})`,
    );
    ok(Math.abs(p.y) < 1.5, `and did not go over the glass (y=${p.y.toFixed(2)})`);
    puck.destroy();
    physics.destroy();
  }
}

section('a shot into the corner stays in the corner');
{
  // Corners are a chain of short board segments; the seams between them are
  // where a fast small body escapes if anything is going to.
  for (const angle of [0.6, 1.1, -0.7, 2.4]) {
    const physics = createPhysicsWorld();
    const puck = createPuck(physics, { position: { x: 0, y: 0.02, z: 0 } });
    puck.setVelocity(Math.sin(angle) * 48, 0, Math.cos(angle) * 48);
    for (let n = 0; n < 5 / DT; n++) physics.step(DT);
    const p = puck.position();
    ok(insideRink(p.x, p.z, 0), `a shot at ${angle.toFixed(1)} rad stayed inside`);
    puck.destroy();
    physics.destroy();
  }
}

section('a dumped puck slides a long way but does stop');
{
  const physics = createPhysicsWorld();
  const puck = createPuck(physics, { position: { x: -RINK.halfX * 0.9, y: 0.02, z: 0 } });
  puck.setVelocity(14, 0, 0);
  let travelled = 0;
  const start = puck.position().x;
  for (let n = 0; n < 6 / DT; n++) physics.step(DT);
  travelled = Math.abs(puck.position().x - start);
  ok(travelled > 15, `it carries down the ice (${travelled.toFixed(1)}m in 6s)`);
  ok(puck.speed() < 14, `and does lose speed (${puck.speed().toFixed(1)} m/s left)`);
  puck.destroy();
  physics.destroy();
}

section('a skater picks up a loose puck');
{
  const { physics, match } = arena(1);
  clearIce(match, [0]);
  match.states[0].x = 0;
  match.states[0].z = 0;
  match.states[0].yaw = Math.PI / 2;
  match.skaters[0].proxy.teleport(0, 0);
  // Drop the puck right where skater 0's blade is.
  match.puck.place(0.8, 0.02, 0.2);
  for (let n = 0; n < 1 / DT; n++) match.update(DT);
  ok(match.possession.carrier === 0, `skater 0 picked it up (carrier=${match.possession.carrier})`);
  physics.destroy();
}

section('a carried puck stays with the skater');
{
  const { physics, match } = arena(1);
  clearIce(match, [0]);
  match.states[0].x = -20;
  match.states[0].z = 0;
  match.states[0].yaw = Math.PI / 2;
  match.skaters[0].proxy.teleport(-20, 0);
  match.puck.place(-20 + 0.8, 0.02, 0);
  match.setControl(0, { x: 1, y: 0, sprint: true, brake: false, cameraYaw: 0 });
  for (let n = 0; n < 0.5 / DT; n++) match.update(DT);
  ok(match.possession.carrier === 0, 'possession established');

  let maxGap = 0;
  for (let n = 0; n < 2.5 / DT; n++) {
    match.update(DT);
    if (match.possession.carrier !== 0) break;
    const p = match.puck.position();
    maxGap = Math.max(maxGap, Math.hypot(p.x - match.states[0].x, p.z - match.states[0].z));
  }
  ok(match.possession.carrier === 0, 'and survived a full-speed rush');
  ok(maxGap < CARRY.breakRadius + 1, `the puck stayed with the stick (worst ${maxGap.toFixed(2)}m)`);
  ok(match.states[0].x > -12, `while actually covering ground (x=${match.states[0].x.toFixed(1)})`);
  physics.destroy();
}

section('the dial does what it says at both ends');
{
  function carryWander(magnetism) {
    const { physics, match } = arena(1);
    clearIce(match, [0]);
    match.states[0].x = -20;
    match.states[0].z = 0;
    match.states[0].yaw = Math.PI / 2;
    match.skaters[0].proxy.teleport(-20, 0);
    match.puck.place(-20 + 0.8, 0.02, 0);
    match.possession.tuning.magnetism = magnetism;
    match.setControl(0, { x: 1, y: 0, sprint: true, brake: false, cameraYaw: 0 });
    for (let n = 0; n < 0.5 / DT; n++) match.update(DT);
    const had = match.possession.carrier === 0;

    let worst = 0;
    let held = 0;
    for (let n = 0; n < 2 / DT; n++) {
      match.update(DT);
      if (match.possession.carrier === 0) {
        held++;
        const p = match.puck.position();
        const c = match.possession.carryPoint(new THREE.Vector3());
        if (c) worst = Math.max(worst, p.distanceTo(c));
      }
    }
    physics.destroy();
    return { had, worst, held: held / (2 / DT) };
  }

  const glued = carryWander(1);
  const loose = carryWander(0.15);
  ok(glued.had && loose.had, 'both settings pick the puck up');
  ok(
    glued.worst < loose.worst,
    `high magnetism keeps the puck tighter to the blade (${glued.worst.toFixed(3)}m vs ${loose.worst.toFixed(3)}m)`,
  );
  ok(glued.held > 0.9, `and holds possession through the rush (${(glued.held * 100).toFixed(0)}% of frames)`);
}

section('shooting sends the puck away and gives up possession');
{
  const { physics, match } = arena(1);
  clearIce(match, [0]);
  match.states[0].x = -10;
  match.states[0].z = 0;
  match.states[0].yaw = Math.PI / 2;
  match.skaters[0].proxy.teleport(-10, 0);
  match.puck.place(-10 + 0.8, 0.02, 0);
  for (let n = 0; n < 0.5 / DT; n++) match.update(DT);
  ok(match.possession.carrier === 0, 'carrying first');

  const fired = match.possession.shoot(1, Math.PI / 2);
  ok(fired, 'the shot fired');
  ok(match.possession.carrier === null, 'and possession was given up');
  ok(match.puck.speed() > 25, `the puck is moving like a shot (${match.puck.speed().toFixed(1)} m/s)`);

  // And it must not be instantly re-captured by the shooter.
  for (let n = 0; n < 0.1 / DT; n++) match.update(DT);
  ok(match.possession.carrier !== 0, 'the shooter cannot immediately vacuum it back up');
  physics.destroy();
}

section('a harder shot travels faster than a soft one');
{
  function fire(power) {
    const { physics, match } = arena(1);
    clearIce(match, [0]);
    match.states[0].x = -10;
    match.states[0].z = 0;
    match.states[0].yaw = Math.PI / 2;
    match.skaters[0].proxy.teleport(-10, 0);
    match.puck.place(-10 + 0.8, 0.02, 0);
    for (let n = 0; n < 0.5 / DT; n++) match.update(DT);
    match.possession.shoot(power, Math.PI / 2);
    const speed = match.puck.speed();
    physics.destroy();
    return speed;
  }
  const soft = fire(0.2);
  const hard = fire(1);
  ok(hard > soft * 2, `full power is far harder than a soft one (${hard.toFixed(1)} vs ${soft.toFixed(1)} m/s)`);
  ok(hard < PUCK.maxSpeed, 'and stays under the ceiling');
}

section('a knockdown loses the puck');
{
  const { physics, match } = arena(1);
  clearIce(match, [0]);
  match.states[0].x = 0;
  match.states[0].z = 0;
  match.skaters[0].proxy.teleport(0, 0);
  match.puck.place(0.8, 0.02, 0.2);
  for (let n = 0; n < 1 / DT; n++) match.update(DT);
  ok(match.possession.carrier === 0, 'carrying first');
  match.skaters[0].goDown(null);
  match.update(DT);
  ok(match.possession.carrier === null, 'going down gives the puck up');
  physics.destroy();
}

section('the Skill Stick moves the puck around the carrier');
{
  const { physics, match } = arena(1);
  clearIce(match, [0]);
  match.states[0].x = 0;
  match.states[0].z = 0;
  match.states[0].yaw = Math.PI / 2;
  match.skaters[0].proxy.teleport(0, 0);
  match.puck.place(0.8, 0.02, 0);
  const control = { x: 0, y: 0, sprint: false, brake: false, cameraYaw: 0, skill: { x: 0, y: 0 }, pressed: {} };
  match.setControl(0, control);
  for (let n = 0; n < 1 / DT; n++) match.update(DT);
  ok(match.possession.carrier === 0, 'carrying first');

  control.skill.x = 1;
  for (let n = 0; n < 0.6 / DT; n++) match.update(DT);
  const right = match.puck.position().clone();
  control.skill.x = -1;
  for (let n = 0; n < 0.6 / DT; n++) match.update(DT);
  const left = match.puck.position().clone();

  // Skater faces +X (yaw = π/2). Mesh-right is local −X (handR side), which
  // is world +Z at that yaw — not the sim's up×forward "right", which is
  // mirrored from the skeleton. Stick-right must follow the mesh.
  ok(
    right.z > left.z + 0.25,
    `stick-right moves the puck to the skater's right (${right.z.toFixed(2)} vs ${left.z.toFixed(2)})`,
  );
  physics.destroy();
}

section('a 3-on-3 with a puck stays sane and produces contact');
{
  // This is the payoff: give six skaters one thing to want and they converge,
  // which is what finally exercises the hit system under normal play instead
  // of only in staged collisions.
  const { physics, match } = arena(3);
  let hits = 0;
  const seen = new Set();
  for (let n = 0; n < 60 / DT; n++) {
    match.update(DT);
    for (const h of match.recentHits) {
      const id = `${h.at}|${h.attacker}|${h.victim}`;
      if (!seen.has(id)) {
        seen.add(id);
        hits++;
      }
    }
  }
  for (let i = 0; i < match.states.length; i++) {
    const s = match.states[i];
    ok(Number.isFinite(s.x) && Number.isFinite(s.z), `skater ${i} finite after 60s`);
    ok(insideRink(s.x, s.z, 0.3), `skater ${i} still on the ice`);
  }
  const p = match.puck.position();
  ok(Number.isFinite(p.x) && Number.isFinite(p.z), 'the puck is finite');
  ok(insideRink(p.x, p.z, 0), `the puck is still on the ice (${p.x.toFixed(1)}, ${p.z.toFixed(1)})`);
  ok(hits > 0, `chasing a puck produced contact without staging it (${hits} hits in 60s)`);
  physics.destroy();
}

done('puck');