ramble 0.9.4: a walkable opening frame, and the map travels with you

[kh0pper]

Two things from walking with 0.9.3: the opening frame was too wide to be a walk, and "following" did not actually follow.

A walkable opening frame

The map opened at zoom 15. Measured at the player's latitude on a phone that is about 1.5 km across, which put most of the visible seed beyond any reasonable walk — and out along a freeway frontage with no footpath, which is worse than merely far.

The operator marked the area he would actually walk: roughly 63% of the frame, about 918 m. Zoom 16 is about 730 m — slightly tighter than marked, which errs on the walkable side. Extracted as WALK_ZOOM rather than left as a second bare 15, since it now appears in two places.

Re-centring via the "Around you" chip keeps Math.max(getZoom(), WALK_ZOOM), so it never zooms you back out past walkable but does keep a tighter zoom you chose yourself.

Following now means centred

paintHere only panned once the marker had drifted outside the middle 40% of the view (getBounds().pad(-0.3)). That reads as the map lurching every few hundred metres rather than travelling with you. It now recentres on any real move.

The threshold stays at 10 m — the same floor the waddle uses, which clears typical high-accuracy GPS jitter (3–15 m), so standing still does not creep the map.

Panning this often is cheap here, and I checked rather than assumed: the moveend work is debounced 500 ms and coalesces, so a continuous walk collapses many pans into one round of fetches. And the area post does not depend on moveend — it has an independent 75 m ratchet inside the geolocation watch, so a walk still reports itself even while pans keep collapsing the debounce.

A manual drag still calls setFollowing(false), so scrolling by hand releases the map and you are never fighting it; the chip turns following back on and recentres.

⚠ Contract change: one test asserted the pad(-0.3) gate. It now asserts the gate is gone and that the 10 m recentre replaced it, with a comment saying why.

Verification

Full suite 4299/4299. check-ports OK, build-registry --check in sync. Backticks 0 and markup sinks 2 in the panel client. Ramble 0.9.3 → 0.9.4.

Not fixed here, and worth a separate decision

Seed appearing along the freeway is not a rendering problem — those cells are genuinely unlocked, and the most likely reason is that they were driven through with the panel open, either live or via the backfill from visit_place credits. The game has no notion of how a cell was entered, so it cannot currently tell a walk from a commute. Options range from a speed gate on unlocking to leaving it alone; that is a design question rather than a bug fix, so it is not in this PR.