nordisk/facett

MapFacet — idle auto-rotate

The map/3D pane spins itself when the user walks away — a screensaver-style "show off the scene" that any interaction instantly cancels. Lives on MapFacet (the shared, source-agnostic map facet), so every map surface inherits it; the funnel/graph panes reuse the same idea.

What it is

• Off by default. Turn on with MapFacet::with_auto_rotate(true) / set_auto_rotate(true).
• Idle-gated. A frame clock (idle_elapsed_s) counts up while the pane is untouched; once it crosses idle_threshold_s (6 s) the camera bearing_deg advances at rotate_speed_deg_s (8 °/s). Any pointer/scroll/key event resets the clock and stops the spin.
• Pure + drivable in code. tick(dt_s, interacted) -> bool takes the frame delta + an "interacted this frame" flag (no wall-clock read), so it is deterministic and testable headlessly. ui() feeds it egui's stable_dt + input-event presence and requests a repaint while spinning.
• Observable. state_json() exposes auto_rotate, idle_rotating, idle_elapsed_s — "see what the user sees" as data.

Coverage (LAW: robot + test-matrix, driven in code)

• Headless robot drive: layer::tests::idle_auto_rotate_spins_only_when_idle drives tick() in code — asserts no spin while interacting → spins after the idle threshold (bearing advances) → a touch resets/stops → off-by-default never spins — reading back through state_json().
• test-matrix cell: emits facett-map / idle_auto_rotate via facett_core::testmatrix::emit (edda nornir-testmatrix) under --features testmatrix.
• Follow-up: the visible watch-on-DISPLAY:0 leg (egui_kittest frame loop, as in tests/robot_callchain.rs) asserting the painted bearing changes across frames.