The renderer's torus mode laid out the world in a 3×3 grid of wrap
copies (TORUS_OFFSETS) so the user could pan past an edge without
seeing a void. Below `minScale = max(viewport/world)` the world
shrinks below the viewport along at least one axis and the wrap
copies become visible side-by-side — the user reported a 9-tile
mosaic that pans and zooms as one rigid unit. The doc explicitly
deferred the fix ("if profiling ever reveals that users do this");
real usage is the trigger.
Apply `clampZoom({ minScale })` in both modes; torus still keeps
free pan (no `clamp({ direction: "all" })`) so the wrap copies
fill the cross-edge slack as designed. Resize re-evaluates the
clamp so a window resize does not strand the camera below the new
floor. Documentation in `ui/docs/renderer.md` updated to describe
the new shared invariant.
Regression test in `tests/e2e/playground-map.spec.ts` wheels out
aggressively in torus mode and asserts `camera.scale >= minScale`
across all four Playwright projects.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Ilia Denisov
cc004f935d