Wire pointer and mouse interaction into TinyVectors physics

[Jesssullivan]

Problem

BlobPhysics exposes updateMousePosition(x, y), but TinyVectors.svelte does not wire pointer or mouse movement into it. Scroll physics currently attracts blobs toward the default physics-center position rather than the actual pointer.

Scope

• Add pointer/mouse handling at the component boundary while preserving pointer-events: none visual behavior where appropriate.
• Convert viewport/client coordinates into the physics coordinate space.
• Use requestAnimationFrame-friendly throttling and consider coalesced pointer events where supported.
• Include touch/pointer fallback behavior for mobile.

Validation

• Unit tests for coordinate mapping.
• Browser-level smoke test or demo verification that pointer movement changes blob trajectories without breaking scroll/passive listeners.

[Jesssullivan]

Implemented the first pointer integration pass locally. The Svelte layer now listens to window-level pointer/mouse movement without making the SVG overlay capture events, maps viewport coordinates into the physics range through a dedicated pointer mapper, rAF-throttles physics mouse updates, and cleans up listeners/rAF state on destroy. Added focused pointer mapper tests and included the new mapper in motion exports. Validation passed with pnpm check, pnpm test, pnpm build, package checks, nix flake check --no-build, Bazel build/typecheck/test, and npm pack/publish dry-runs.

[Jesssullivan]

Working-tree update, not committed yet:

• Added PointerMapper for deterministic client-coordinate to physics-space mapping with clamping and zero-area bounds behavior.
• Added PointerPhysicsController with pointer/mouse fallback, coalesced-event sampling, requestAnimationFrame throttling, and deterministic cleanup.
• TinyVectors.svelte now uses the shared controller behind enablePointerPhysics.

Covered by new unit tests and included in the full local validation pass.

[Jesssullivan]

Local physical/algo review on PR #39 head 84a7fc8:

• Pointer is wired into BlobPhysics.updateMousePosition, but current physics consumes it only through scroll stickiness in applyScrollEffect().
• Runtime Chrome/CDP trials show right/bottom pointer + wheel clearly pulls toward the pointer target: avg distance delta -3.86, centroid +8.96 x, +8.52 y; pointer-off averaged +7.94 away from that target.
• Left/top corner pull is noisier: x direction is correct, but mean distance only improved in 2/4 trials because wall/territory/repulsion terms fight the corner.

Interpretation: pointer integration is real as a scroll-pull aim point, but it is not yet a standalone mouse/gel reaction. If we want direct mouse feel, add a low-budget pointer influence term/config after accounting for the 10.98 KiB gzip bundle pressure.

[Jesssullivan]

Planning update: pointer work should now route through TIN-853 / #40. Pointer interaction should be a local soft field: nearby blobs react more than distant blobs, the visual layer still does not capture events, and pointer should influence ambient flow directly rather than only aiming scroll stickiness.

[Jesssullivan]

Pushed d4b8778 fix(pointer): reset canceled pointer io to PR #39.\n\nPointer physics now listens for browser pointercancel when Pointer Events are available and resets the sampled pointer position to center, canceling pending rAF work. This covers touch/gesture interruptions where pointer IO can stop without a viewport exit or window blur.\n\nAlso updated:\n- public PointerCancelEventName type export through /motion and root entry points\n- package consumer type check for the new type\n- Chrome/CDP listener lifecycle probe to assert pointercancel attach/cleanup\n- README and feel-contract liveness docs\n\nValidation on this head before push:\n- pnpm vitest run tests/unit/pointer-physics-controller.test.ts (14 tests)\n- pnpm run check\n- pnpm run test (169 tests)\n- pnpm run build\n- pnpm run check:release-metadata\n- pnpm run check:package\n- pnpm run check:bundle-size (10.73 KiB gzip, 0.27 KiB target headroom)\n- pnpm run test:browser:motion\n- nix develop . --command bazel build //:pkg //:package_consumer_check //:bundle_size_check //:typecheck //:test --verbose_failures\n- pnpm run check:package-consumer\n- npm pack --dry-run ./bazel-bin/pkg\n- npm publish --dry-run --ignore-scripts --access public ./bazel-bin/pkg

[Jesssullivan]

PR #39 follow-up pushed: 8197ffd fix(motion): block reduced-motion permission race.

This covers the iOS-style edge case where requestDeviceMotionPermission() is in flight and prefers-reduced-motion changes to reduce before the browser permission promise resolves. The request now resolves false, emits neutral motion, avoids starting the deviceorientation listener, and still restarts cleanly if reduced motion later changes back after permission was granted.

Validation refreshed: pnpm run test is now 170 tests, plus pnpm run check, pnpm run build, pnpm run check:release-metadata, pnpm run check:package, pnpm run check:bundle-size at 10.73 KiB gzip, and pnpm run test:browser:motion.

[Jesssullivan]

Browser harness follow-up pushed: c03793f test(browser): cover reduced-motion listener lifecycle.

pnpm run test:browser:motion now uses Chrome/CDP media emulation to verify prefers-reduced-motion: reduce neutralizes active motion, removes the deviceorientation listener, and restoring no-preference reattaches exactly one orientation listener before CDP orientation continues to move blob geometry.

[Jesssullivan]

Motion compatibility follow-up pushed: 63c3e52 fix(motion): support legacy reduced-motion listeners.

DeviceMotion now handles both modern MediaQueryList.addEventListener/removeEventListener and legacy Safari-style addListener/removeListener for prefers-reduced-motion changes. This keeps reduced-motion gating and cleanup active on older iOS/Safari surfaces that are also likely to require explicit orientation permission.

Validation refreshed locally: pnpm run check, pnpm run test (171 tests), pnpm run build, pnpm run check:bundle-size (10.74 KiB gzip, 0.26 KiB target headroom), and pnpm run test:browser:motion.

[Jesssullivan]

PR #39 pointer follow-up at c8d0bbe:

• Fixed consecutive pointer velocity samples to diff against the current pointer anchor instead of the previous lastMouseX/Y snapshot.
• Added regression coverage for consecutive pointer movement.
• Validation is green locally: pnpm run check, pnpm run test (180 tests), pnpm run check:bundle-size (10.90 KiB gzip, 0.10 KiB target headroom), and pnpm run test:browser:motion.
• GitHub Actions and Greptile are green on the current head.

[Jesssullivan]

Follow-up branch/PR for direct pointer feel: PR #41 (jess/pointer-field-followup) stacked on PR #39.

• Adds a low-strength local pointer field after real pointer input.
• Reset-to-center remains neutral, so canceled/blurred pointer IO does not preserve stale attraction.
• Removes dead private last-pointer anchor state while keeping pointer velocity regression coverage.
• Validation is green locally: pnpm run check, pnpm run test (181 tests), pnpm run build, pnpm run check:bundle-size (11.00 KiB gzip, effectively at target and below the 12.00 KiB gate), and pnpm run test:browser:motion.

Next pointer slice should add tolerant browser locality probes before any stronger tuning.

[Jesssullivan]

PR #41 CI update:

• Draft PR Add local pointer field #41 (jess/pointer-field-followup) is stacked on PR Integrate motion, pointer, gel, and package validation #39 and has GitHub Actions green.
• The slice adds the first low-strength local pointer field while keeping reset-to-center neutral.
• Local validation remains: pnpm run check, pnpm run test (181 tests), pnpm run build, pnpm run check:bundle-size (11.00 KiB gzip, below 12.00 KiB gate), and pnpm run test:browser:motion.
• Greptile has not created a review record for the stacked draft PR yet.

[Jesssullivan]

PR #41 follow-up pushed: 5641f28 test(browser): cover CDP pointer delivery.

The Chrome/CDP browser probe now dispatches a real pointer move while pointer physics is active and records pointerDelivery in the JSON output. Local validation: node --check scripts/probe-motion-cdp.mjs, pnpm run test:browser:motion (Chrome 147, pointerDelivery.events: 1), pnpm run check, and pnpm run test (181 tests).