Ease a late zoomed tilt to its new limit instead of jumping there

From 400 km, a tilt to -5° that a zoom out x2.5 caught at -8.0005° reported -8°, and the next frame jumped to -9.407° and ended there. The zoom kept the camera's pitch as the goal when it was already past the new range's horizon limit, but at the same pivot pitch the longer range looks down more steeply, so the next lookAt dropped the camera 1.4° at once.

The zoom now re-solves the pivot pitch so the new range keeps the camera's pitch, and aims the tilt at the asked angle or the new limit, even when that limit is below where the camera stands: the tilt eases down to it. The zoom's reply names that end, and the camera reaches it with no frame moving more than 0.1°.

docs/CURRENT-STATE.md

@@ -5590,7 +5590,7 @@ and unreachable upstream (502/504) separately from road geometry.
 > branch: **2,281 on Node 25.6.1** (allocation suites skipped) = 2,255 on
 > `main` + 26 route pins; the same tree on Node 24 reports 2,295.
 
-- **Camera verbs** (`src/cameraVerbs.js`) — one motion slot, driven per clock tick. `move_camera` orbits/pans/tilts/rotates; `fly_route` is a cinematic dolly along an existing route annotation. `rotate_globe` rotates the world-space camera rigidly around Earth's center using its screen-up axis, preserving geocentric range and framing. Left/right describe visible globe motion, while `rotate` turns the camera in place. `tilt` swings the camera about the ground under the crosshair, so the place stays centred and the heading is kept. It tilts in place instead with no ground under the crosshair, from beyond 1,000 km of range, or while an entity is tracked (voice releases the follow camera before moving, so a voice tilt from a tracked view still pivots); pitch stays within -89° to -5°, clamped only in the direction of travel so a top-down (-90°) view can tilt up out of it. Angles and limits are the camera's own pitch; at regional range the pivot's pitch is up to about 8° shallower (the Earth curves away), so the swing solves for the pivot pitch that gives the camera the angle asked for. A pivot swing toward the horizon lowers the camera (height above the pivot is range × sin|pitch|), so the swing stops lowering it at 150 m above the pivot (not above the terrain behind the camera) and the rest of the tilt happens in place. Beyond about 17 km of range the swing never hands over to an in-place tilt (that would lift the crosshair onto the sky); it keeps the camera at least 0.5° above the place's own horizon, which from roughly 500 km stops it short of -5° with the place still centred: a tilt to an angle beyond that stops at the angle reached and says so (`pitchDeg` is the angle reached, with a `note`), a continuous tilt stops there, and a further tilt up is refused as at the limit. A zoom during a pivoting tilt scales the range it holds, as for orbit, but a zoom in stops at the range that keeps that 150 m clearance; a zoom that can move no further (that floor, the 80 m floor, or the cap: 1,000 km for a tilt, where pivoting stops, and 5,000 km for an orbit) is reported as not zoomed. A zoom during a tilt to an angle re-judges the place's horizon limit at the new range: when that moves where the tilt ends, the tilt eases from where it is to the new end, and the zoom's result names that angle (`pitchDeg`) with a `note`. Once the tilt continues in place, a zoom moves the camera like any zoom. A tilt with `pitchDeg` (or with neither angle nor direction, which means -45°) eases to that angle; a positive angle means the same angle below the horizon. `pitchDeg` is absolute, not a step: sent with a `direction` it contradicts, the tilt is refused. An angle the camera already holds answers `unchanged` but still takes navigation, so it stops a running motion and releases the follow camera. A tilt left or right is refused. A voice tilt, orbit, pan or rotate sent while a voice `fly_to_location` is still looking up or flying ("fly to London and tilt the camera" or "fly to Paris and orbit it" arrives as two sibling calls) waits for that flight to land, up to 15 s (moving to a later fly-to in the same reply as soon as it begins, whatever the earlier one reports), so it neither cancels the flight nor gets replaced by it; if the flight is cancelled, finds nothing or times out, the user grabs, touches or scrolls the map during it, or another navigation (a location-panel search, share link or file import, which leave the flight flying) takes the camera during it, the motion is not run and says so. A motion that runs after a fly-to of the same reply has already found nothing (Gemini runs one turn's calls one by one, and passes its turn as the reply) is refused the same way rather than moving the old view; a motion in a later reply runs. `stop` and `rotate_globe` do not wait, and a motion sent before its fly-to is not reordered: it runs at once, and the fly-to's result names the motion it stopped (`stoppedMotion`). Orbit still arms (`armed: 'waiting-for-arrival'`) when it starts during any other camera flight, and captures its target once the tween queue has been quiet for 0.8 s. Omitted globe direction/mode default to right/continuous; explicit values prevail. Other camera motions keep their once default. Admission requires 3D, no Cockpit/tracking owner and the whole globe inside the existing keyhole circle, using the shared keyhole/projection geometry and vertical camera FOV with a rotation-local bounding-sphere cone for off-axis containment. Canvas-edge clipping alone does not block a rigid rotation or its unchanged Globe View preset. There is no altitude cutoff. An already smaller, fully framed globe rotates directly; repeated nudges, direction and speed changes recheck current framing without demanding a reset merely because ellipsoid altitude varied. A close-up or overlap refuses without moving the camera. When the unchanged Globe View preset fits, voice says “Globe rotation isn’t available from this view. You can say Line truncated
+- **Camera verbs** (`src/cameraVerbs.js`) — one motion slot, driven per clock tick. `move_camera` orbits/pans/tilts/rotates; `fly_route` is a cinematic dolly along an existing route annotation. `rotate_globe` rotates the world-space camera rigidly around Earth's center using its screen-up axis, preserving geocentric range and framing. Left/right describe visible globe motion, while `rotate` turns the camera in place. `tilt` swings the camera about the ground under the crosshair, so the place stays centred and the heading is kept. It tilts in place instead with no ground under the crosshair, from beyond 1,000 km of range, or while an entity is tracked (voice releases the follow camera before moving, so a voice tilt from a tracked view still pivots); pitch stays within -89° to -5°, clamped only in the direction of travel so a top-down (-90°) view can tilt up out of it. Angles and limits are the camera's own pitch; at regional range the pivot's pitch is up to about 8° shallower (the Earth curves away), so the swing solves for the pivot pitch that gives the camera the angle asked for. A pivot swing toward the horizon lowers the camera (height above the pivot is range × sin|pitch|), so the swing stops lowering it at 150 m above the pivot (not above the terrain behind the camera) and the rest of the tilt happens in place. Beyond about 17 km of range the swing never hands over to an in-place tilt (that would lift the crosshair onto the sky); it keeps the camera at least 0.5° above the place's own horizon, which from roughly 500 km stops it short of -5° with the place still centred: a tilt to an angle beyond that stops at the angle reached and says so (`pitchDeg` is the angle reached, with a `note`), a continuous tilt stops there, and a further tilt up is refused as at the limit. A zoom during a pivoting tilt scales the range it holds, as for orbit, but a zoom in stops at the range that keeps that 150 m clearance; a zoom that can move no further (that floor, the 80 m floor, or the cap: 1,000 km for a tilt, where pivoting stops, and 5,000 km for an orbit) is reported as not zoomed. A zoom during a tilt to an angle re-judges the place's horizon limit at the new range: when that moves where the tilt ends, the tilt eases from where it is to the new end (holding the camera's pitch through the range change, and easing back down to a limit it is already past rather than jumping there), and the zoom's result names that angle (`pitchDeg`) with a `note`. Once the tilt continues in place, a zoom moves the camera like any zoom. A tilt with `pitchDeg` (or with neither angle nor direction, which means -45°) eases to that angle; a positive angle means the same angle below the horizon. `pitchDeg` is absolute, not a step: sent with a `direction` it contradicts, the tilt is refused. An angle the camera already holds answers `unchanged` but still takes navigation, so it stops a running motion and releases the follow camera. A tilt left or right is refused. A voice tilt, orbit, pan or rotate sent while a voice `fly_to_location` is still looking up or flying ("fly to London and tilt the camera" or "fly to Paris and orbit it" arrives as two sibling calls) waits for that flight to land, up to 15 s (moving to a later fly-to in the same reply as soon as it begins, whatever the earlier one reports), so it neither cancels the flight nor gets replaced by it; if the flight is cancelled, finds nothing or times out, the user grabs, touches or scrolls the map during it, or another navigation (a location-panel search, share link or file import, which leave the flight flying) takes the camera during it, the motion is not run and says so. A motion that runs after a fly-to of the same reply has already found nothing (Gemini runs one turn's calls one by one, and passes its turn as the reply) is refused the same way rather than moving the old view; a motion in a later reply runs. `stop` and `rotate_globe` do not wait, and a motion sent before its fly-to is not reordered: it runs at once, and the fly-to's result names the motion it stopped (`stoppedMotion`). Orbit still arms (`armed: 'waiting-for-arrival'`) when it starts during any other camera flight, and captures its target once the tween queue has been quiet for 0.8 s. Omitted globe direction/mode default to right/continuous; explicit values prevail. Other camera motions keep their once default. Admission requires 3D, no Cockpit/tracking owner and the whole globe inside the existing keyhole circle, using the shared keyhole/projection geometry and vertical camera FOV with a rotation-local bounding-sphere cone for off-axis containment. Canvas-edge clipping alone does not block a rigid rotation or its unchanged Globe View preset. There is no altitude cutoff. An already smaller, fully framed globe rotates directly; repeated nudges, direction and speed changes recheck current framing without demanding a reset merely because ellipsoid altitude varied. A close-up or overlap refuses without movinLine truncated
   - **The route dolly is shaped, not linear** (2026-08-20). A trapezoid speed profile (smoothstep up, cruise, smoothstep down, distance taken as the closed-form integral) eases both ends without changing the pace — duration is still `totalM / ROUTE_M_S[speed]`, with one exception: a 0.5 s minimum keeps a degenerate route from being an instant teleport, so routes under 10 m (slow) / 20 m (normal) / 45 m (fast) fly SLOWER than the speed word, never faster. Turns bank up to **10°** (a 90° street corner settles near 7.5°), measured as a triangular pulse over a 4 s window centred on the camera so the roll leads in and unwinds after. Altitude breathes ±20 m around the 260 m mean and lifts up to 26 m into turns. Pitch is LOCKED at −32°; heading comes from a gaze that leads the path by 6.5 s of travel. `prefers-reduced-motion` zeroes the roll and the altitude shaping and keeps the easing.
   - **Invariants — do not "fix" these.** (1) **Every** release levels the roll: completion unwinds it through the ease-out envelope, and `interruptCameraMotion` zeroes it synchronously (heading/pitch/position preserved). Cesium keeps the last up vector it was handed, so skipping this leaves the user holding a tilted horizon. (2) Heading is interpolated as an ANGLE about the local up, never as a Cartesian lerp — a lerp cannot cross an antipodal pair, so an out-and-back route looked backwards for the entire return leg; `signedTurnRad` branches the exact-180° case deterministically because the cross product's sign there is a floating-point coin toss. (3) A COLD floor cell is missing data, not flat ground: route vertices carry height 0, so trusting them flew a mountain corridor at 260 m above the ELLIPSOID. The corridor warm is fire-and-forget, so the dolly ARMS — camera untouched, no teleport onto the route — for up to 1.2 s waiting for real floor data, falls back to a rendered-mesh probe (`scene.sampleHeight`) when the DEM stays cold — latched to ONE firing per flight, for exactly the cells the cache could not answer, so a route costs at most 8 `sampleHeight` calls however long it arms — and otherwise holds the launch altitude for the whole route. A corridor is only RESOLVED when every cell is accounted for: one warm cell says nothing about the ground under the other seven, and treating it as an answer let the dolly descend to 460 m over a 1,600 m rendered surface. The probe reads the rendered surface at the current LOD (rooftops and primitives included) — a better estimate than nothing, not a guaranteed upper bound. Never descend blind. The floor is SMOOTHED in both directions for the ride while the hard clearance clamp reads the RAW sample, so a cell boundary cannot pop the eye but a cliff is still cleared on the frame it is seen. A pre-departure floor is adopted whole; one arriving mid-flight is eased onto, and the eye's descent rate is capped.
   - Pins: `src/routeCinematics.test.mjs` (26 tests), with `scripts/qa-flyroute-mutations.mjs` reverting each fix individually to prove they are load-bearing (19 named defects); rendered proof `scripts/qa-flyroute-cinema.mjs` (drives the real voice runner, measures the real Cesium camera every frame, writes a labelled contact sheet).