Display and query terrain data

Start with the map's feature collections.

Map features use the read-only map-scoped OGC Features service. Each rendered feature layer is a dynamiclayer--UUID collection. Use blue:layer_type to distinguish boundaries, named areas, annotations, and other content, then follow advertised links.

curl --silent --show-error --fail-with-body \
  --header "Authorization: Bearer $BLUE_API_KEY" \
  "$BLUE_API_URL/api/maps/$BLUE_MAP_ID/ogc/features/collections"

{
  "id": "layer--7d307d4e-46c4-4f6a-909f-9e7d62cd5b19",
  "title": "Area of Operations",
  "blue:map_layer_id": "7d307d4e-46c4-4f6a-909f-9e7d62cd5b19",
  "blue:layer_type": "boundary",
  "links": [
    {
      "rel": "items",
      "href": "https://service-blue.exialabs.com/api/maps/MAP_ID/ogc/features/collections/layer--7d307d4e-46c4-4f6a-909f-9e7d62cd5b19/items",
      "type": "application/geo+json"
    }
  ]
}

Reusable terrain products are advertised by the global OGC Tiles catalog.

curl --silent --show-error --fail-with-body \
  --header "Authorization: Bearer $BLUE_API_KEY" \
  "$BLUE_API_URL/api/ogc/tiles/collections"

Query boundaries and named areas as GeoJSON.

Find the collection you need by its blue:layer_type, then follow its items link. Items endpoints support bbox, datetime, limit, and offset. The default limit is 100 and the maximum is 1000.

export BLUE_LAYER_ID="LAYER_UUID_FROM_COLLECTION"

curl --silent --show-error --fail-with-body \
  --header "Authorization: Bearer $BLUE_API_KEY" \
  "$BLUE_API_URL/api/maps/$BLUE_MAP_ID/ogc/features/collections/layer--$BLUE_LAYER_ID/items?bbox=-104.90,38.80,-104.70,38.95&limit=100"

Use the global catalog for reusable terrain tiles.

Tile addresses use tileMatrix = zoom, tileRow = y, andtileCol = x. Use the collection's tileset metadata for its format and supported zoom limits.

curl --silent --show-error --fail-with-body \
  --header "Authorization: Bearer $BLUE_API_KEY" \
  --output terrain-tile.png \
  "$BLUE_API_URL/api/ogc/tiles/collections/blue-native--terrain-elevation/tiles/WebMercatorQuad/ZOOM/TILE_ROW/TILE_COLUMN.png"

Interpret each product according to its encoding.

• Elevation PNG: alpha 0 is nodata; otherwise packed = R × 65536 + G × 256 + B and meters are -10000 + packed × 0.1.
• Land-cover PNG: alpha 0 is nodata and the red channel contains the raw ESA land-cover category.
• Roads, population, soil, and buildings are MVT; each source-layer name matches its collection ID.
• Send If-None-Match with a prior ETag and accept 304 as an unchanged authenticated representation.