What problem does it solve? MapLibre fleet maps silently misrepresent ledger truth: exceptions on symbol-layer trucks never pulse, parked trucks snap to due-north headings, and high-latitude bearings skew east. This Skill encodes the laws and fixes that keep every rendered alarm and heading equal to the ledger record. ## Core Features & Use Cases - Exception-halo parity: Adds a kind-independent circle halo layer under every mark so exceptions throb on the 1.6s urgent sine whether the mark is a circle or a symbol. - Heading correctness: Prevents bearing overwrites from zero glide deltas and applies cos(latitude) correction to atan2 bearing math, with test vectors for regression. - Paint-only updates: Enforces setFeatureState/setPaintProperty for status changes instead of full setData re-renders, and routes cluster alarms through maxStatus properties. - Use Case: When adding a new EntityKind to entities.ts that can hold an exception, use this Skill to wire the halo filter, world-dim exemption, and reduced-motion frame so the new kind never renders dimmed-but-silent. ## Quick Start Ask the AI to review the truck exception pulse and heading logic in MapCanvas.tsx and entities.ts using this skill before editing the map layers.
