Base map

ExpTech serves three base-map tile sets. Each has a TileJSON, so you can use it directly as a MapLibre GL JS source:

Tiles	Format	Contents
Base map	Vector (`.pbf`)	World land, boundaries of Taiwan counties, cities, townships, towns, and districts, and coastal segments for tsunami warnings
Terrain	Raster (`.png`, Terrain-RGB)	Taiwan elevation, for hillshade or 3D terrain
Streets and buildings	Vector (`.pbf`, OpenMapTiles schema)	Taiwan roads, buildings, water, place names, points of interest, and more, from OpenStreetMap

These three tile sets do not change with time. They do not need a time list.

Data license

Base map, TerrainAttribution · Commercial use OK
AttributionData: ExpTech Studio (exptech.dev)
Streets & buildingsAttribution · Commercial use OK
AttributionData: © OpenStreetMap contributors, © OpenMapTiles, ExpTech Studio (exptech.dev)

Upstream terms

OpenStreetMap: OpenStreetMap data is licensed under the ODbL: show "© OpenStreetMap contributors" on the map and link to https://www.openstreetmap.org/copyright .
OpenMapTiles: Tiles built on the OpenMapTiles schema must show "© OpenMapTiles".

Where to show it, examples and commercial-use requests: Data licensing and attribution.

Authentication

No API Token is required. Responses include Access-Control-Allow-Origin: *, so a browser can load them cross-origin.

Base map

GEThttps://lb.exptech.dev/api/v1/map/tiles/tiles.json

Commercial OK

ServerLB

Request

curl "https://lb.exptech.dev/api/v1/map/tiles/tiles.json"

const res = await fetch("https://lb.exptech.dev/api/v1/map/tiles/tiles.json");
if (!res.ok) throw new Error(`HTTP ${res.status}`);
const data = await res.json();
console.log(data);

import requests

res = requests.get("https://lb.exptech.dev/api/v1/map/tiles/tiles.json", timeout=10)
res.raise_for_status()
print(res.json())

Response

200

TileJSON 2.0.0 (excerpt)

{
  "tilejson": "2.0.0",
  "name": "ExpTech Studio Map",
  "format": "pbf",
  "minzoom": 0,
  "maxzoom": 12,
  "bounds": [
    -180,
    -85.051129,
    180,
    83.634101
  ],
  "attribution": "ExpTech Studio Map",
  "tiles": [
    "https://lb.exptech.dev/api/v1/map/tiles/{z}/{x}/{y}.pbf"
  ]
}

Try it

GEThttps://lb.exptech.dev/api/v1/map/tiles/{z}/{x}/{y}.pbf

Commercial OK

ServerLB

Path parameters

zintegerRequired
Zoom level. The range is minzoom / maxzoom in the TileJSON.
xintegerRequired
XYZ tile column.
yintegerRequired
XYZ tile row (north to south).

Request

curl -o output.pbf --compressed "https://lb.exptech.dev/api/v1/map/tiles/<z>/<x>/<y>.pbf"

const res = await fetch("https://lb.exptech.dev/api/v1/map/tiles/<z>/<x>/<y>.pbf");
if (!res.ok) throw new Error(`HTTP ${res.status}`);
const blob = await res.blob();

import requests

res = requests.get(
    "https://lb.exptech.dev/api/v1/map/tiles/<z>/<x>/<y>.pbf",
    timeout=10,
)
res.raise_for_status()
with open("output.pbf", "wb") as f:
    f.write(res.content)

Response

200204

Mapbox Vector Tile (Content-Type: application/octet-stream). Some tiles are gzip-compressed (Content-Encoding: gzip)binary MVT

No tile at this position (no content)No response body

Try it

Layers (source-layer)

source-layer	Geometry	Contents
`global`	Polygon	World land
`city`	Polygon	Taiwan counties and cities
`town`	Polygon	Taiwan townships, towns, and districts
`tsunami`	Line	Coastal segments for tsunami warnings

Property fields for each layer have no published schema and may change.

Terrain

GEThttps://lb.exptech.dev/api/v1/map/terrain/terrain.json

Commercial OK

ServerLB

Request

curl "https://lb.exptech.dev/api/v1/map/terrain/terrain.json"

const res = await fetch("https://lb.exptech.dev/api/v1/map/terrain/terrain.json");
if (!res.ok) throw new Error(`HTTP ${res.status}`);
const data = await res.json();
console.log(data);

import requests

res = requests.get("https://lb.exptech.dev/api/v1/map/terrain/terrain.json", timeout=10)
res.raise_for_status()
print(res.json())

Response

200

TileJSON 2.0.0 (excerpt)

{
  "tilejson": "2.0.0",
  "name": "ExpTech Studio Terrain",
  "format": "png",
  "encoding": "mapbox",
  "minzoom": 0,
  "maxzoom": 12,
  "bounds": [
    120.0166,
    21.8939,
    122.0096,
    25.3015
  ],
  "attribution": "ExpTech Studio Map",
  "tiles": [
    "https://lb.exptech.dev/api/v1/map/terrain/{z}/{x}/{y}.png"
  ]
}

Try it

GEThttps://lb.exptech.dev/api/v1/map/terrain/{z}/{x}/{y}.png

Commercial OK

ServerLB

Path parameters

zintegerRequired
Zoom level. The range is minzoom / maxzoom in the TileJSON.
xintegerRequired
XYZ tile column.
yintegerRequired
XYZ tile row (north to south).

Request

curl -o output.png "https://lb.exptech.dev/api/v1/map/terrain/<z>/<x>/<y>.png"

const res = await fetch("https://lb.exptech.dev/api/v1/map/terrain/<z>/<x>/<y>.png");
if (!res.ok) throw new Error(`HTTP ${res.status}`);
const blob = await res.blob();

import requests

res = requests.get(
    "https://lb.exptech.dev/api/v1/map/terrain/<z>/<x>/<y>.png",
    timeout=10,
)
res.raise_for_status()
with open("output.png", "wb") as f:
    f.write(res.content)

Response

200

image/png, 512 × 512 Terrain-RGB. A position with no data returns a flat image at sea level (0 m)binary image/png

Try it

Tiles are 512 × 512 Terrain-RGB PNGs (mapbox encoding). Elevation in meters:

const elevation = -10000 + (r * 256 * 256 + g * 256 + b) * 0.1;

A position outside coverage or without data does not return 204. It returns a 512 × 512 image for sea level (0 m), which MapLibre raster-dem can use directly.

Streets and buildings

GEThttps://lb.exptech.dev/api/v1/map/gsi/gsi.json

Commercial OK

ServerLB

Request

curl "https://lb.exptech.dev/api/v1/map/gsi/gsi.json"

const res = await fetch("https://lb.exptech.dev/api/v1/map/gsi/gsi.json");
if (!res.ok) throw new Error(`HTTP ${res.status}`);
const data = await res.json();
console.log(data);

import requests

res = requests.get("https://lb.exptech.dev/api/v1/map/gsi/gsi.json", timeout=10)
res.raise_for_status()
print(res.json())

Response

200

TileJSON 2.0.0 (excerpt)

{
  "tilejson": "2.0.0",
  "name": "ExpTech Studio GSI (Taiwan roads & buildings)",
  "format": "pbf",
  "minzoom": 0,
  "maxzoom": 14,
  "bounds": [
    114.28579,
    10.32677,
    122.3283,
    26.43722
  ],
  "attribution": "© OpenStreetMap contributors © OpenMapTiles",
  "tiles": [
    "https://lb.exptech.dev/api/v1/map/gsi/{z}/{x}/{y}.pbf"
  ]
}

Try it

GEThttps://lb.exptech.dev/api/v1/map/gsi/{z}/{x}/{y}.pbf

Commercial OK

ServerLB

Path parameters

zintegerRequired
Zoom level. The range is minzoom / maxzoom in the TileJSON.
xintegerRequired
XYZ tile column.
yintegerRequired
XYZ tile row (north to south).

Request

curl -o output.pbf --compressed "https://lb.exptech.dev/api/v1/map/gsi/<z>/<x>/<y>.pbf"

const res = await fetch("https://lb.exptech.dev/api/v1/map/gsi/<z>/<x>/<y>.pbf");
if (!res.ok) throw new Error(`HTTP ${res.status}`);
const blob = await res.blob();

import requests

res = requests.get("https://lb.exptech.dev/api/v1/map/gsi/<z>/<x>/<y>.pbf", timeout=10)
res.raise_for_status()
with open("output.pbf", "wb") as f:
    f.write(res.content)

Response

200204

Mapbox Vector Tile (Content-Type: application/octet-stream). Some tiles are gzip-compressed (Content-Encoding: gzip)binary MVT

No tile at this position (no content)No response body

Try it

Built from OpenStreetMap data for Taiwan, using the OpenMapTiles layer schema, and covering Taiwan only. Common source-layers: transportation, transportation_name, building, water, waterway, water_name, landcover, landuse, park, aeroway, aerodrome_label, boundary, place, poi, mountain_peak, housenumber. Properties for each layer are in the OpenMapTiles documentation. When you use them, you must show “© OpenStreetMap contributors © OpenMapTiles”.

TileJSON fields

Field	Type	Description
`tilejson`	`string`	TileJSON specification version. Currently 2.0.0.
`name`	`string`	Tile set name.
`format`	`string`	pbf (vector) or png (terrain).
`encoding`	`string`	Terrain only. The value is mapbox (Terrain-RGB encoding).
`minzoom`	`integer`	Minimum zoom level.
`maxzoom`	`integer`	Maximum zoom level. Above this, scale up this level's tiles.
`bounds`	`number[4]`	Coverage [west, south, east, north], in degrees.
`center`	`number[3]`	Suggested initial center [longitude, latitude, zoom].
`attribution`	`string`	Attribution text that must be shown.
`tiles`	`string[]`	Tile URL templates (absolute URLs).

Advanced examples

Use all three tile sets in one MapLibre GL JS style. Create each source from the TileJSON url, and the zoom range and coverage are read automatically. The attribution inside the TileJSON is not the full suggested credit. Set attribution on the source yourself, as below (it replaces the TileJSON value):

const MAP = "https://lb.exptech.dev";

const map = new maplibregl.Map({
  container: "map",
  center: [121, 23.7],
  zoom: 7,
  style: {
    version: 8,
    sources: {
      // Base map: global / city / town / tsunami
      exptech: { type: "vector", url: `${MAP}/api/v1/map/tiles/tiles.json`, attribution: "Data: ExpTech Studio (exptech.dev)" },
      // Terrain: Terrain-RGB (mapbox encoding)
      terrain: { type: "raster-dem", url: `${MAP}/api/v1/map/terrain/terrain.json`, tileSize: 512, encoding: "mapbox", attribution: "Data: ExpTech Studio (exptech.dev)" },
      // Taiwan streets and buildings: OpenMapTiles schema
      gsi: { type: "vector", url: `${MAP}/api/v1/map/gsi/gsi.json`, attribution: "Data: © OpenStreetMap contributors, © OpenMapTiles, ExpTech Studio (exptech.dev)" },
    },
    layers: [
      { id: "background", type: "background", paint: { "background-color": "#1f2329" } },
      { id: "land", type: "fill", source: "exptech", "source-layer": "global", paint: { "fill-color": "#3e4147" } },
      { id: "county", type: "fill", source: "exptech", "source-layer": "city", paint: { "fill-color": "#4b4e55" } },
      { id: "hillshade", type: "hillshade", source: "terrain", paint: { "hillshade-exaggeration": 0.3 } },
      { id: "roads", type: "line", source: "gsi", "source-layer": "transportation", paint: { "line-color": "#8a8f98", "line-width": 1 } },
      { id: "buildings", type: "fill", source: "gsi", "source-layer": "building", minzoom: 13, paint: { "fill-color": "#5a5e66" } },
      { id: "town-line", type: "line", source: "exptech", "source-layer": "town", paint: { "line-color": "#a9b4bc", "line-width": 0.4 } },
      { id: "county-line", type: "line", source: "exptech", "source-layer": "city", paint: { "line-color": "#a9b4bc", "line-width": 1 } },
    ],
  },
});

Notes

Use the tiles URLs from the TileJSON. They are absolute URLs. The host name can differ from the TileJSON host. Do not replace it yourself.
When a vector tile (.pbf) has no data, the response is 204 (no content), which is a different status from 404. MapLibre skips it.
Some vector tiles are returned with Content-Encoding: gzip. Browsers and MapLibre decompress them. Other clients must handle it themselves (add --compressed to curl).
Terrain tiles are 512 × 512. Set tileSize: 512 on a MapLibre raster-dem source.
Zoom range and coverage follow the TileJSON response. The excerpts on this page can differ from the live values.
Responses have no Cache-Control. These tiles rarely change, so you can cache them on the client.