Move with collision reacts along the contact normal: it travels to the surface, stays flush and slides the rest of the move along it with Coulomb friction (the mean of both colliders, a tile counts as 0.5), a circle now rolls over an edge instead of catching on it, pushed dynamic bodies move off along the normal, Move gains the outputs hit, normal x and normal y, an object without its own collider moves freely, and editor run and play share the same path through Solids; contact point and normal come from our own f64 geometry (contactBetween), because Rapier's castShape lands 3e-6 px inside the wall in f32 (#150)

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

tools/e2e/41-physics.mjs

@@ -33,6 +33,34 @@ const walkGraph = {
   ],
 };
 
+/**
+ * Rolls its owner right at 120 per second with "Collide with solids" on, and logs Move's normal
+ * (x, then y) on every frame that hits something.
+ */
+const BALL_R = 20;
+const CORNER_DROP = 12;
+const rollGraph = {
+  nodes: [
+    node('pr-update', 'OnUpdate', 0, 0),
+    node('pr-owner', 'Owner', 0, 160),
+    node('pr-move', 'Move', 300, 0, { dx: 1, scale: WALK, collide: true }),
+    node('pr-hit', 'Branch', 600, 0),
+    node('pr-log-x', 'Log', 850, 0),
+    node('pr-log-y', 'Log', 1100, 0),
+  ],
+  edges: [
+    edge('pr-e1', 'pr-update', 'exec', 'pr-move', 'exec'),
+    edge('pr-e2', 'pr-update', 'dt', 'pr-move', 'dt'),
+    edge('pr-e3', 'pr-owner', 'object', 'pr-move', 'object'),
+    edge('pr-e4', 'pr-move', 'exec', 'pr-hit', 'exec'),
+    edge('pr-e5', 'pr-move', 'hit', 'pr-hit', 'condition'),
+    edge('pr-e6', 'pr-hit', 'then', 'pr-log-x', 'exec'),
+    edge('pr-e7', 'pr-move', 'normalX', 'pr-log-x', 'message'),
+    edge('pr-e8', 'pr-log-x', 'exec', 'pr-log-y', 'exec'),
+    edge('pr-e9', 'pr-move', 'normalY', 'pr-log-y', 'message'),
+  ],
+};
+
 /**
  * A point of a panel (`panel` and `point` are hook expressions), scrolled into view first: a
  * collider's material rows sit below the fold of the inspector, and after the earlier steps the
@@ -305,10 +333,67 @@ export async function physics(t) {
   const hints = consoleLog.filter((line) => line.includes('[physics]')).slice(hintsBefore);
   check('nothing in the step made the physics hint at a no-op', hints.length === 0, hints.join(' | '));
 
-  await mutate(`
+  const clearPhysics = () =>
+    mutate(`
     const p = __gm.state.project;
     const scene = __gm.state.activeScene;
     scene.objects = scene.objects.filter((o) => !o.id.startsWith('phys-'));
     p.assets = p.assets.filter((a) => !a.id.startsWith('phys-'));
     __gm.state.select(null)`);
+  await clearPhysics();
+
+  // 41d. Move along the contact normal (#150): a ball walked straight right into the upper-left
+  //      corner of a block, 12 below its centre, rolls up over it instead of hanging on the corner,
+  //      and its graph logs the normal of the first contact from Move's hit / normal outputs.
+  const edgeLog = consoleLog.length;
+  await mutate(`
+    const scene = __gm.state.activeScene;
+    const assets = __gm.state.project.assets;
+    ${MAKE_OBJECT}
+    const asset = structuredClone(assets.find((a) => a.id === 'mover'));
+    Object.assign(asset, { id: 'phys-roll', name: 'Physics roll', props: { enabled: true, runInEditor: false }, variables: [], graph: ${JSON.stringify(rollGraph)} });
+    assets.push(asset);
+    assets.push({ id: 'phys-col-ball', type: 'collider', name: 'phys-col-ball', props: { shape: 'circle', width: 40, height: 40, radius: ${BALL_R}, isTrigger: false } });
+    assets.push({ id: 'phys-col-block', type: 'collider', name: 'phys-col-block', props: { shape: 'box', width: 100, height: 60, radius: 20, isTrigger: false } });
+    const put = (id, assetId, parentId, x, y, name, overrides = {}) => {
+      const o = make(id, assetId, parentId, y, name);
+      o.position.x = x;
+      o.overrides = overrides;
+      scene.objects.push(o);
+    };
+    put('phys-ball', 'crate', '', 0, ${Y}, 'Rolling ball', { width: 40, height: 40 });
+    put('phys-ball-col', 'phys-col-ball', 'phys-ball', 0, 0);
+    put('phys-ball-roll', 'phys-roll', 'phys-ball', 0, 0, 'Roll');
+    put('phys-block', 'crate', '', 150, ${Y + CORNER_DROP + 30}, 'Edge block', { width: 100, height: 60 });
+    put('phys-block-col', 'phys-col-block', 'phys-block', 0, 0);
+    __gm.state.select(null)`);
+  await play();
+  await sleep(2000);
+  const ball = await json(
+    `(() => { const e = __gm.world()?.entities.find((x) => x.objectId === 'phys-ball'); return e && { x: e.worldX, y: e.worldY }; })()`,
+  );
+  await stop();
+  const top = Y + CORNER_DROP - BALL_R; // the ball's centre when it rolls along the block's top face
+  check(
+    'Move rolls a ball up over the edge it runs into, onto the top face',
+    ball && ball.x > 150 && ball.y <= top + 0.01 && ball.y > top - 3,
+    JSON.stringify({ ball, top }),
+  );
+  const lines = consoleLog.slice(edgeLog).filter((line) => line.startsWith('[behavior '));
+  const logged = lines
+    .filter((line) => line.startsWith('[behavior Roll]'))
+    .map((line) => Number(line.split(']').pop()));
+  const reach = Math.sqrt(BALL_R ** 2 - CORNER_DROP ** 2);
+  check(
+    "Move's hit and normal outputs: the first contact faces from the corner to the ball's centre",
+    logged.length >= 2 &&
+      Math.abs(logged[0] + reach / BALL_R) < 1e-6 &&
+      Math.abs(logged[1] + CORNER_DROP / BALL_R) < 1e-6,
+    JSON.stringify({
+      logged: logged.slice(0, 4),
+      expected: [-reach / BALL_R, -CORNER_DROP / BALL_R],
+      lines: lines.slice(0, 4),
+    }),
+  );
+  await clearPhysics();
 }