feat(core): support pointer-anchored zoom in GlobeView

[charlieforward9]

Goal

Add stable pointer-anchored zoom to GlobeView through the same controller and transition contracts used by the other views, without Globe-specific branches in shared controller code.

This PR is the Globe-specific half of the maintainer-requested stack:

• feat(core): configure zoom anchors across controllers #10595 adds the shared zoomAround controller option across Map, Orbit, Orthographic, and FirstPerson, including padded viewport-center handling
• feat(core): support pointer-anchored zoom in GlobeView #10385 adds the GlobeViewport capability and Globe integration on top

Supersedes the fork-based #10307.

Changes

• teaches GlobeViewport.panByPosition to preserve a geographic anchor during zoom using spherical ray math
• damps correction near the globe limb and falls back to center behavior for far off-globe pointers
• resolves off-globe anchors before they enter the shared wheel, pinch, double-click, or double-click-drag paths, so zoom still changes scale without pulling the camera toward a phantom point
• follows the shortest wrapped longitude delta across the antimeridian
• routes GlobeState constraints and LinearInterpolator anchoring through the generic viewport contract
• keeps the existing globe drag form of panByPosition intact
• splits demo UI into settings-control.js, with the same pointer/center control operating in both Globe and Map views
• removes the old localStorage path and updates the point radius accessor

Validation

• focused stacked Vitest: 92/92 across controllers, LinearInterpolator, and GlobeViewport
• regression proof: the new off-globe controller test fails on the previous head with a 1.25738° longitude shift and passes on this head
• yarn
• yarn build
• yarn lint
• pre-commit checks: 15/15
• yarn test-headless: 216/217 files and 985 tests passed; the only failure is the unrelated loading-widget.spec.ts spinner assertion, reproduced identically on the untouched feat(core): configure zoom anchors across controllers #10595 base
• Greptile green on 8d771b0cdb; GitHub Actions had not created a run for the synchronized SHA at the latest check
• no unresolved review threads before the push
• exact-head dev server: http://127.0.0.1:41085/
• live Globe stress QA with no console errors:
  • pointer anchoring at the interior, damped near-limb behavior, and center fallback outside the visible sphere
  • center anchoring with asymmetric padding, preserving longitude/latitude to floating-point precision
  • shortest-path anchoring across the antimeridian
  • finite behavior at latitude 84° and zoom 7
  • wheel, pinch, double-click, and enabled double-click-drag off-globe fallback
  • 100 alternating wheel events at one anchor return to the initial view state within floating-point precision
  • Globe → Map → Globe switching preserves the shared pointer policy; Map anchor error was 2.6e-12px and Globe anchor error was 0.41px

[coveralls]

Coverage is 82.265% — codex/globe-anchored-zoom into codex/shared-controller-zoom-anchor. No base build found for codex/shared-controller-zoom-anchor.

[ibgreen-openai]

I wonder if this could be split into stacked PR, one that adds general things like zoomStart, zoomEnd and other plumbing, and then the globe specific feature could be a much smaller, easier review on top of that?

[chrisgervang]

Agree with @ibgreen, since this changes a lot of core functionality I'd prefer to split the PRs up and test each of them in the stack

[greptile-apps]

Greptile Summary

This PR adds pointer-anchored zoom support to GlobeView through the generic controller, viewport, constraint, and transition contracts.

• Adds spherical anchor correction with limb damping, off-globe fallback, and wrapped-longitude handling.
• Enables anchored Globe transitions through LinearInterpolator.
• Expands controller, transition, and viewport coverage and updates the Globe demonstration controls.

Confidence Score: 5/5

The PR appears safe to merge.

No blocking failure remains.

Important Files Changed

Filename	Overview
modules/core/src/controllers/globe-controller.ts	Integrates Globe zoom anchoring with generic constraint handling and falls back to center anchoring for off-globe pointers.
modules/core/src/viewports/globe-viewport.ts	Adds shared ray geometry, anchor-strength damping, wrapped longitude correction, and descriptive parameter names while preserving drag behavior.
modules/core/src/transitions/linear-interpolator.ts	Removes the Globe-specific exclusion so transition anchoring uses the common viewport contract.
test/modules/core/viewports/globe-viewport.spec.ts	Covers on-globe stability, limb behavior, off-globe fallback, and antimeridian wrapping.
test/apps/globe/app.js	Updates the Globe demo with shared Map/Globe and pointer/center controls and corrects the point-radius accessor.

Sequence Diagram

sequenceDiagram
  participant Input as Pointer input
  participant Controller as GlobeController
  participant State as GlobeState
  participant Viewport as GlobeViewport
  Input->>Controller: wheel/pinch/double-click at screen position
  Controller->>Viewport: getZoomAnchorStrength(position)
  alt Pointer can anchor globe
    Controller->>State: zoom around pointer
    State->>Viewport: panByPosition(anchor, screenPosition)
    Viewport-->>State: corrected longitude and latitude
  else Pointer is far off globe
    Controller->>State: zoom around projected center
    State->>Viewport: panByPosition(center, centerPixel)
    Viewport-->>State: unchanged longitude and latitude
  end

Loading

_{Reviews (6): Last reviewed commit: "fix(core): center globe zoom outside vis..." | Re-trigger Greptile}

[charlieforward9]

@ibgreen-openai @chrisgervang I made the physical split you asked for.

• feat(core): configure zoom anchors across controllers #10595 is the view-agnostic base: one controller option, applied through the existing wheel, pinch, pinch-inertia, double-click, and double-click-drag paths, with cross-view tests.
• feat(core): support pointer-anchored zoom in GlobeView #10385 now targets that branch and contains the GlobeViewport math, GlobeState/transition integration, and the demo/tests only.
• The demo UI is split into settings-control.js, the old localStorage try/catch is gone, and the same pointer/center toggle operates in both Globe and Map views.

The stacked #10385 diff is now 8 files. Fresh post-stack focused tests are 90/90; the unchanged source tree also passed build, lint, test-website, and live Globe pointer/center plus Map pointer verification.

[charlieforward9]

I stress-tested this against the exact stacked head today and found one real Globe edge case before asking for review: an off-globe pixel could still be unprojected into a phantom anchor once the target zoom made the sphere larger.

Fixed in 8d771b0cdb. The boundary stays the one we agreed on:

• feat(core): configure zoom anchors across controllers #10595 still owns the view-agnostic zoomAround policy and shared input paths
• feat(core): support pointer-anchored zoom in GlobeView #10385 now resolves Globe anchor validity once in GlobeController.getZoomPosition
• GlobeViewport still owns the spherical geometry and limb damping
• no shared wheel, pinch, double-click, or double-click-drag handler has a Globe branch

The regression test fails on the previous head with a 1.25738° longitude shift and passes here. I also exercised interior/limb/off-globe pointers, asymmetric padding, antimeridian wrapping, latitude 84° at zoom 7, pinch, double-click, enabled double-click-drag, 100 alternating wheel events, and Globe → Map → Globe switching.

Local gates are green: 92/92 focused tests, yarn, yarn build, yarn lint, and 15/15 pre-commit checks. Greptile is green on the new SHA. @ibgreen-openai @chrisgervang @felixpalmer this should now be the small Globe-specific layer on top of the shared controller PR that you asked for.