feat(pipeline): re-bake 154 morphs all-intra for smooth scrub seeking (LFS)

Per plan Task 7. Every frame now a keyframe (verified 93/93 I-frames on a sample),
so the scrub interaction seeks to arbitrary frames smoothly. Total transitions
173M -> 504M; largest clip ~5.8M (well under the 25MB LFS/proxy ceiling).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

simulator/build_pool_manifest.py

@@ -399,6 +399,28 @@ def _adjacent_edges() -> list[tuple[str, str]]:
     return [(RING_ORDER[i], RING_ORDER[(i + 1) % n]) for i in range(n)]
 
 
+# All-intra H.264: every frame a keyframe, so the scrub interaction can seek to an
+# arbitrary frame smoothly (a sparse GOP scrubs "steppy"). Files grow, but each clip
+# stays well under the LFS/proxy ceiling. (Scrub-driven-transitions design §4.)
+ALL_INTRA = ["-c:v", "libx264", "-g", "1", "-keyint_min", "1", "-sc_threshold", "0", "-pix_fmt", "yuv420p"]
+
+
+def transition_cmd(ff: str, a: str, b: str, out: str) -> list[str]:
+    """The ffmpeg argv for a forward (zoom-in) member-pair morph, baked all-intra."""
+    norm = "trim=0:3,setpts=PTS-STARTPTS,scale=1280:720,fps=25,setsar=1,format=yuv420p"
+    return [
+        ff, "-y", "-i", str(a), "-i", str(b), "-filter_complex",
+        f"[0:v]{norm}[a];[1:v]{norm}[b];"
+        "[a][b]xfade=transition=zoomin:duration=1.5:offset=0.75,format=yuv420p[v]",
+        "-map", "[v]", "-an", *ALL_INTRA, str(out),
+    ]
+
+
+def reverse_cmd(ff: str, forward: str, out: str) -> list[str]:
+    """The ffmpeg argv for the zoom-OUT companion (forward played backward), all-intra."""
+    return [ff, "-y", "-i", str(forward), "-vf", "reverse", "-an", *ALL_INTRA, str(out)]
+
+
 def _make_transition(ff: str, src_clip: str, dst_clip: str) -> Path:
     """A zoom/warp morph between two CLIP MEMBERS' base footage (the well-liked
     orbit-coast recipe), keyed by clip id so every adjacent member pair gets its
@@ -407,13 +429,7 @@ def _make_transition(ff: str, src_clip: str, dst_clip: str) -> Path:
     b = MEDIA / dst_clip / "base.mp4"
     out = MEDIA / "transitions" / f"{src_clip}__{dst_clip}.mp4"
     out.parent.mkdir(parents=True, exist_ok=True)
-    norm = "trim=0:3,setpts=PTS-STARTPTS,scale=1280:720,fps=25,setsar=1,format=yuv420p"
-    subprocess.run([
-        ff, "-y", "-i", str(a), "-i", str(b), "-filter_complex",
-        f"[0:v]{norm}[a];[1:v]{norm}[b];"
-        "[a][b]xfade=transition=zoomin:duration=1.5:offset=0.75,format=yuv420p[v]",
-        "-map", "[v]", "-an", str(out),
-    ], check=True, capture_output=True)
+    subprocess.run(transition_cmd(ff, str(a), str(b), str(out)), check=True, capture_output=True)
     return out
 
 
@@ -423,9 +439,7 @@ def _make_reverse(ff: str, forward: Path) -> Path:
     crosses its edge `reversed`; the renderer then plays this file, so zooming out
     recedes from the current scale back to the higher one instead of zooming in."""
     out = forward.with_suffix(".rev.mp4")
-    subprocess.run([
-        ff, "-y", "-i", str(forward), "-vf", "reverse", "-an", str(out),
-    ], check=True, capture_output=True)
+    subprocess.run(reverse_cmd(ff, str(forward), str(out)), check=True, capture_output=True)
     return out
 
 

simulator/e2e/tests/altitude-lock.spec.ts

@@ -29,6 +29,54 @@ async function wheelOnStage(page: Page, deltaY: number) {
   await page.locator("#stage").dispatchEvent("wheel", { deltaY });
 }
 
+// The Audio toggle is a visually-hidden checkbox styled as a switch; set it + fire
+// `change` directly (headless Chromium relaxes the autoplay gesture requirement).
+async function enableAudio(page: Page) {
+  await page.evaluate(() => {
+    const c = document.querySelector("#audio") as HTMLInputElement;
+    c.checked = true;
+    c.dispatchEvent(new Event("change", { bubbles: true }));
+  });
+}
+
+test("two audio elements exist for crossfade", async ({ page }) => {
+  await boot(page);
+  const n = await page.evaluate(() => document.querySelectorAll("audio#aud, audio#aud-b").length);
+  expect(n).toBe(2);
+});
+
+test("dragging the dial scrubs morph currentTime and audio gains", async ({ page }) => {
+  await boot(page);
+  await enableAudio(page);                                 // hidden custom toggle → set + dispatch change
+  const box = (await page.locator("#dial").boundingBox())!;
+  const cx = box.x + box.width / 2, cy = box.y + box.height / 2;
+  await page.mouse.move(cx, cy - 30);
+  await page.mouse.down();
+  await page.mouse.move(cx + 18, cy - 24, { steps: 8 });  // partial clockwise turn (~0.5 detent)
+  // The currentTime seek is throttled to one rAF; wait for it to land.
+  await page.waitForFunction(() => (document.querySelector("video") as HTMLVideoElement).currentTime > 0, null, { timeout: 5000 });
+  const state = await page.evaluate(() => ({
+    t: (document.querySelector("video") as HTMLVideoElement).currentTime,
+    ga: (document.querySelector("#aud") as HTMLAudioElement).volume,
+    gb: (document.querySelector("#aud-b") as HTMLAudioElement).volume,
+  }));
+  expect(state.t).toBeGreaterThan(0);          // morph scrubbed off frame 0
+  expect(state.gb).toBeGreaterThan(0);         // next scale fading in
+  expect(state.ga).toBeLessThan(1);            // current scale fading out
+  await page.mouse.up();
+});
+
+test("wheel auto-scrubs one altitude and locks", async ({ page }) => {
+  await boot(page);
+  const start = (await page.locator("#scale-name").textContent())!;
+  await wheelOnStage(page, 60);                          // wheel down = descend one altitude
+  await page.waitForFunction((s) => document.querySelector("#scale-name")?.textContent !== s, start, { timeout: 20000 });
+  const landed = (await page.locator("#scale-name").textContent())!;
+  expect(landed).toContain("orbit");
+  await page.waitForTimeout(1500);
+  expect(await page.locator("#scale-name").textContent()).toBe(landed);    // locked
+});
+
 test("zoom in plays the matching morph, lands locked, and stays put while parked", async ({ page }) => {
   await boot(page);
   const start = (await page.locator("#scale-name").textContent())!;
@@ -57,35 +105,57 @@ test("zoom in plays the matching morph, lands locked, and stays put while parked
   expect((await morphs(page)).length).toBe(countAfterLanding);           // no extra swap
 });
 
-test("zoom back out plays a reverse morph and lands locked", async ({ page }) => {
+test("turn-back scrubs the same morph in reverse and re-locks the start clip", async ({ page }) => {
   await boot(page);
-  const start = (await page.locator("#scale-name").textContent())!;
+  await enableAudio(page);
+  const box = (await page.locator("#dial").boundingBox())!;
+  const cx = box.x + box.width / 2, cy = box.y + box.height / 2;
+  const read = () => page.evaluate(() => ({
+    t: (document.querySelector("video") as HTMLVideoElement).currentTime,
+    ga: (document.querySelector("#aud") as HTMLAudioElement).volume,
+    gb: (document.querySelector("#aud-b") as HTMLAudioElement).volume,
+    name: document.querySelector("#scale-name")?.textContent,
+    morphs: ((window as any).__hefMorphs || []).slice(),
+  }));
 
-  // Zoom in one detent to get off cosmos (-> orbit)...
-  await wheelOnStage(page, 60);
-  await page.waitForFunction(
-    (s) => document.querySelector("#scale-name")?.textContent !== s,
-    start,
-    { timeout: 20_000 },
-  );
-  const atOrbit = (await page.locator("#scale-name").textContent())!;
-  expect(atOrbit).toContain("orbit");
+  await page.mouse.move(cx, cy - 30);
+  await page.mouse.down();
+  await page.mouse.move(cx + 22, cy - 20, { steps: 10 });   // descend partway into the segment
+  await page.waitForFunction(() => (document.querySelector("video") as HTMLVideoElement).currentTime > 0, null, { timeout: 5000 });
+  const fwd = await read();
+  // The single segment morph is the descend/forward file (cosmos__orbit), NOT a `.rev`.
+  expect(fwd.morphs[fwd.morphs.length - 1]).toMatch(/^transitions\/cosmos.*\.mp4$/);
+  expect(fwd.morphs[fwd.morphs.length - 1]).not.toMatch(/\.rev\.mp4$/);
 
-  // ...then zoom back OUT to cosmos.
-  await wheelOnStage(page, -60);
-  await page.waitForFunction(
-    (s) => document.querySelector("#scale-name")?.textContent !== s,
-    atOrbit,
-    { timeout: 20_000 },
-  );
+  await page.mouse.move(cx + 4, cy - 30, { steps: 10 });    // turn back toward the start
+  await page.waitForTimeout(120);                           // let the throttled rAF seek land
+  const back = await read();
+  await page.mouse.up();
 
-  const played = await morphs(page);
-  // The most recent morph is the zoom-out: a `.rev` companion. Its file is named
-  // for the descending pair (cosmos<...>__orbit<...>), so it starts "cosmos".
-  expect(played[played.length - 1]).toMatch(/^transitions\/cosmos.*\.rev\.mp4$/);
-
-  const landed = (await page.locator("#scale-name").textContent())!;
-  expect(landed).toContain("cosmos");
-  await page.waitForTimeout(2500);
-  expect(await page.locator("#scale-name").textContent()).toBe(landed);   // locked
+  expect(back.t).toBeLessThan(fwd.t);          // SAME morph file, seeking backward
+  expect(back.gb).toBeLessThan(fwd.gb);        // next-scale audio receding
+  expect(back.name).toContain("cosmos");       // re-locked the altitude we left
+});
+
+test("crossing a detent commits and locks the destination clip", async ({ page }) => {
+  await boot(page);
+  const box = (await page.locator("#dial").boundingBox())!;
+  const cx = box.x + box.width / 2, cy = box.y + box.height / 2;
+  // Drag clockwise across one full detent (top -> right ~= 90deg = 1.25 detents),
+  // crossing integer 1 (orbit) so it commits, then hold past it (no auto-complete).
+  await page.mouse.move(cx, cy - 30);
+  await page.mouse.down();
+  await page.mouse.move(cx + 30, cy + 6, { steps: 14 });
+  await page.waitForFunction(() => (window as any).__hefState().ringIndex === 1, null, { timeout: 5000 });
+  const st = await page.evaluate(() => (window as any).__hefState());
+  expect(st.ringIndex).toBe(1);                          // committed to orbit
+  expect(String(st.activeClipId)).toMatch(/^orbit/);     // locked the destination pool pick
+  const played = await page.evaluate(() => (window as any).__hefMorphs || []);
+  expect(played[0]).toMatch(/^transitions\/cosmos.*\.mp4$/);
+  expect(played[0]).not.toMatch(/\.rev\.mp4$/);
+  // Hold: the committed clip does not change while parked mid-gesture.
+  await page.waitForTimeout(800);
+  const st2 = await page.evaluate(() => (window as any).__hefState());
+  expect(st2.activeClipId).toBe(st.activeClipId);
+  await page.mouse.up();
 });