Map View and Selection Tools

Primary page: /parcels/map/

Viewer Mode Controls

  • Zoom to all parcels
  • Label toggle
  • State As Of datetime filter (ref_ts)
  • Settings side panel (style/range + raster background controls)
  • Parcel side panel (details)
  • Selection dropdown + Deselect button

Background Raster Controls (Map Settings)

Open Map Settings and use:

  • Basemap: OpenStreetMap / Satellite / None
  • DEM: choose a DEM dataset or None
  • DEM Render: Default Style, Elevation, Hillshade, or Elevation + Hillshade
  • DEM opacity slider
  • Landcover: choose a landcover dataset or None
  • Landcover opacity slider
  • DEM and landcover legends are loaded from selected dataset metadata and shown in the floating Legends panel
  • Each legend section in the Legends panel can be collapsed/expanded
  • Basemap/DEM/Landcover selections and opacity settings are remembered in this browser

Overlay order is fixed:

  • basemap at bottom
  • DEM/Landcover overlays above basemap
  • parcels above all raster overlays

Live Cursor Readout

Bottom-right readout updates live while moving the mouse on the map:

  • line 1: projected x y coordinates (UTM/projection from UTM_EPSG)
  • next lines: sampled raster values for selected overlays, shown as slug value
  • DEM example: srtm30 25 m
  • landcover example: esawcv22021 10 - Tree cover

Sampling uses persisted query source rasters under RASTER_QUERY_ROOT.
If a dataset was ingested before this feature, re-ingest it to enable value sampling.

Historical Map View (State As Of)

Use the State As Of datetime input in the map HUD to load parcel state for a historical timestamp.

  • Leave blank for current state
  • Set a timestamp to view historical geometry/attributes
  • When historical mode is active, the HUD shows a Historical view: YYYY-MM-DD HH:MM badge

Shape-Based Selection

Selection UI includes:

  • Selection Rule
  • Any touching polygon
  • Centroid within shape
  • Polygon totally within shape
  • Selection shape tools
  • Rectangle drag
  • Circle drag
  • Polygon draw

Selection request flow:

  1. User draws shape
  2. Client POSTs payload to /parcels/api/select/
  3. Server applies PostGIS predicate against visible parcels
  4. Selected IDs are written into tab-scoped selection store
  5. Map updates highlight and selection count

Deselect

Use Deselect button to clear all selected parcels in the current tab.

Visual Emphasis of Selected Parcels

Selected polygons remain in their existing thematic colors but receive stronger visual emphasis (shadow/glow) so they stand out clearly.