The Phase 29 visibility fog ("visible hyperspace") froze the whole UI on
large reports in Safari while staying smooth in Firefox. Root cause: the
fog is a layered overpaint (torus mode = 9 world-sized rects + 9xN
near-world-sized opaque circles, ~270 fills for KNNTS041) and Pixi's
continuous auto-render loop re-rasterised all of it every frame, even
while idle. Safari's WebGPU backend cannot sustain that fillrate, so the
main thread/compositor starved and the entire UI froze.
Stage 1 (vector-preserving, no rasterisation):
- Stop Pixi's auto-render loop (app.stop()) and paint on demand via a
single Ticker.shared flush gated on viewport.dirty (camera) plus an
internal requestRender() from every content mutation (fog / hide-set /
extras / wrap mode / resize / pick overlay). An idle map now does zero
GPU work per frame; plain hover paints nothing.
- Remove the decelerate (drag-inertia) plugin: a released drag stops
instantly (owner request) and the viewport goes idle immediately.
- Expose RendererHandle.getRenderCount() / getMapRenderCount for
deterministic e2e assertions.
Tests: new map-toggles e2e specs (idle map does not repaint; released
drag does not coast) green on all four Playwright projects incl. WebKit.
Docs: renderer.md (render-on-demand section; fog section corrected to the
current single-fogLayer model; FPS note) and PLAN.md Phase 29 decision 8.
If Safari pan is still heavy after this, stage 2 will cut the overpaint
itself with an inverse stencil mask of the circle union (kept vector).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Ilia Denisov