Feed wheel: a turn back is a plain notch again, with no wind-up for a moment. The "hunt" on a reversal (3ff588d: a quarter-size notch settling fast, then four growing ones) read as a stutter on every change of direction and a slow patch after it (Adam, 2026-10-16: "it stutters and sometimes when I'm scrolling it slows down for a while"). Now a reversal still catches the coast at once, and the notch travels its full distance at the usual pace; for 700 ms after it notches don't wind the speed up, so a couple of correcting notches travel a couple of notches rather than launching a flight the other way — which was the complaint the hunt had answered. tools/feed-wheel-reverse-test.js (full travel on a reversal, a reversal plus a quick notch vs two wound-up ones from rest, a reversal against a coast that only just died); feed-momentum-test passes.HEADmaster

Co-Authored-By: Claude Fable 5.1 <[email protected]>
Claude-Session: https://claude.ai/code/session_01J1Kon8bxJoHRpJdSzshCkp

1 files changed, 21 insertions, 30 deletions

diff --git a/src/app.js b/src/app.js
index 7f6baa3..5575cc5 100644
--- a/src/app.js
+++ b/src/app.js
@@ -6653,63 +6653,54 @@ if (INTENT_URI) {
     if (!raf && v) { last = performance.now(); raf = requestAnimationFrame(tick); }
   };
   // ---- the wheel
-  // A turn back against the coast is a reader who flew past the post they
-  // wanted and is hunting for it: the page is caught at once, and that notch
-  // and the next few are short, quick steps (a quarter of a notch's travel,
-  // settling fast) rather than a fresh flight the other way. Each notch on
-  // in the same direction grows the step back towards a full one, so a few
-  // flicks have the wheel flying again; a turn back while hunting starts the
-  // small steps over, and a pause ends the hunt — the next notch is the
-  // plain push from rest it has always been.
-  const HUNT = [0.25, 0.35, 0.5, 0.7, 0.85]; // of a notch's travel, notch by notch
-  const HUNT_TAU = 110; // ms: a hunting step settles quickly
-  const HUNT_IDLE = 2000; // ms without a notch, and the hunt is over
-  let hunt = -1, huntDir = 0, huntAt = 0; // the next HUNT entry while hunting
-  const halt = () => { stop(); hunt = -1; };
+  // A turn back against the coast catches the page at once and is a plain
+  // notch from rest — no flight the other way, since for a moment after a
+  // reversal (CALM) notches don't wind the speed up, so a couple of
+  // correcting notches travel a couple of notches. (A spell of quarter-size
+  // "hunting" notches ramping back up was tried here and felt like a
+  // stutter and a slow patch — Adam, 2026-10-16.)
+  const CALM = 700; // ms after a reversal without wind-up
+  let calmUntil = 0; // (lastDir/lastMoveAt: the tick's, above)
   let smoothUntil = 0; // a trackpad's events were just seen: hands off
   window.addEventListener('wheel', (e) => {
     if (e.ctrlKey || e.shiftKey || e.defaultPrevented) return;
     const notch = e.deltaMode === 1 || (e.wheelDeltaY && e.wheelDeltaY % 120 === 0 && !e.deltaX);
-    if (!notch) { smoothUntil = e.timeStamp + 400; halt(); return; }
+    if (!notch) { smoothUntil = e.timeStamp + 400; stop(); return; }
     if (e.timeStamp < smoothUntil || matchMedia('(pointer: coarse)').matches || !inScope(e.target)) return;
     e.preventDefault();
     const px = e.deltaMode === 1 ? e.deltaY * 40 : e.deltaY;
     const dir = Math.sign(px);
     if (!dir) return;
     const now = e.timeStamp;
-    if (hunt >= 0 && now - huntAt > HUNT_IDLE) hunt = -1;
-    // the way the page is going: its coast, the coast that just died, or the hunt
-    const going = v ? Math.sign(v) : now - lastMoveAt < 400 ? lastDir : hunt >= 0 ? huntDir : 0;
-    if (going && dir !== going) { stop(); hunt = 0; huntDir = dir; }
-    else if (hunt >= 0 && ++hunt >= HUNT.length) hunt = -1;
-    if (hunt >= 0) {
+    // the way the page is going: its coast, or the coast that only just died
+    const going = v ? Math.sign(v) : now - lastMoveAt < 400 ? lastDir : 0;
+    if (going && dir !== going) {
       // A reversal catches the old coast immediately. Discard its fractional
       // step and frame clock too: after a busy frame, applying the NEW velocity
       // to the OLD elapsed time made the first reverse step jump. Give the
-      // notch a small response now, then a quick coast over the rest of its
-      // (short) travel; quick flicks still add up.
-      huntAt = now;
-      const travel = px * 3 * HUNT[hunt];
-      const first = dir * Math.min(16, Math.abs(travel / HUNT_TAU) * 16);
+      // notch a small response now, then coast the rest of its travel.
+      stop();
+      calmUntil = now + CALM;
+      const first = dir * Math.min(16, Math.abs(px * 3 / TAU) * 16);
       window.scrollBy({ top: first, behavior: 'instant' });
       lastDir = dir; lastMoveAt = now;
-      coast(v + (travel - first) / HUNT_TAU, HUNT_TAU);
+      coast((px * 3 - first) / TAU, TAU);
     } else {
       // A notch into a page already moving pushes harder: the faster it
       // goes, the more each turn adds (up to 2.5x), so keeping the wheel
       // turning winds the speed up instead of settling at a stroll. From
       // rest a notch is the same push as ever.
-      const gain = 1 + Math.min(1.5, Math.abs(v) / 4);
+      const gain = now < calmUntil ? 1 : 1 + Math.min(1.5, Math.abs(v) / 4);
       coast(v + (px * 3 * gain) / TAU, TAU);
     }
   }, { passive: false });
   // anything else that moves the page takes over from a coast
-  window.addEventListener('keydown', (e) => { if (/^(Arrow|Page|Home|End| )/.test(e.key)) halt(); });
-  window.addEventListener('touchstart', halt, { passive: true });
+  window.addEventListener('keydown', (e) => { if (/^(Arrow|Page|Home|End| )/.test(e.key)) stop(); });
+  window.addEventListener('touchstart', stop, { passive: true });
   // ---- grab and flick
   let drag = null;
   document.addEventListener('pointerdown', (e) => {
-    if (raf) halt(); // a click catches a coasting page, like a finger does
+    if (raf) stop(); // a click catches a coasting page, like a finger does
     if (e.pointerType !== 'mouse' || e.button !== 0 || !inScope(e.target)) return;
     drag = { x: e.clientX, y: e.clientY, ly: e.clientY, on: false, pts: [] };
   });