route-data-flow

"/home/yossef/notes/git/projects/inguide/flows/route-data-flow.md"

path: inguide/flows/route-data-flow.md

- **fileName**: route-data-flow
- **Created on**: 2026-06-16 00:48:42

route-data-flow

cs# route-data-flow

Purpose: Complete data path from user tapping a route on the map to AR waypoint rendering.

Chain

1. User places pins / searches room on map
   →  maplibra_web/src/pathfinding/route-compute.js
   →  Portal engine or legacy A* computes path through graph

2. Route rendered, bridge notified
   →  maplibra_web/src/path-renderer/route.js:33
   →  window.AndroidBridge.onRouteComputed(JSON.stringify(route))

3. Native MapBridge receives route JSON
   →  app/.../ui/map/MapScreen.kt:832 (onRouteComputed)
   →  routeData.value = payload (string)

4. MainScreen parses into ArRouteData
   →  app/.../ui/main/MainScreen.kt:146-151 (derivedStateOf)
   →  parseRouteJson() extracts waypoints + connectors
   →  Computes totalDistance via Haversine, ~1.4m/s walk duration

5. AR screen receives parsed route
   →  app/.../ui/main/MainScreen.kt:337-345
   →  ArNavigationScreen(initialRouteData = parsedArRouteData)

6. ViewModel processes route
   →  app/.../ar/ArNavigationViewModel.kt:20-26 (setRoute)
   →  State → Navigating(route) if waypoints non-empty

7. Camera + waypoints rendered
   →  CameraX Preview bound to PreviewView
   →  CoordinateRegistration.toArPosition() → [east, north, floorHeight]
   →  ArWaypointRenderer → up to 4 rendered waypoints
   →  Canvas draws circles + connecting lines on camera feed

Data Formats

Web → Android (bridge JSON)

{
  "lineFeatures": [{ "type":"Feature", "geometry":{ "type":"LineString", "coordinates":[[lng,lat],...] }, "properties":{"floorId":"...","kind":"route-line"} }],
  "connectorFeatures": [{ "type":"Feature", "geometry":{ "type":"Point", "coordinates":[lng,lat] }, "properties":{"floorId":"...","connectorLabel":"Stairs up","connectionType":"stairs"} }]
}

Android → AR (ArRouteData)

ArRouteData(
    waypoints = [ArWaypoint(lng, lat, floorId, label?, isTransition, connectionType?)],
    totalDistance = <haversine-sum>,
    estimatedDuration = <distance/1.4>,
    startFloorId = waypoints[0].floorId
)

continue:[[]]
before:[[]]