Maplat is the cool Historical Map/Illustrated Map Viewer API.
It can transform each map coordinates with nonlinear but homeomorphic projection and makes possible that the maps can collaborate with GPS/accurate maps, without distorting original maps.
This is part of Maplat project.
日本語版はこちらをご覧ください。
- Node.js: Version 20 or 22 (tested in CI)
- pnpm: Version 9 or higher
- Required Library: OpenLayers (Architecture requirement)
- Optional Libraries: MapLibre GL JS or Mapbox GL JS (For vector tile support etc.)
You can use MaplatCore directly in the browser using ES Modules and a CDN. Note that you must include OpenLayers CSS and JS.
<!-- OpenLayers CSS (Required) -->
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/ol@latest/ol.css" />
<!-- OpenLayers JS (Required) -->
<script src="https://cdn.jsdelivr.net/npm/ol@latest/dist/ol.js"></script>
<script type="module">
import { MaplatApp } from 'https://cdn.jsdelivr.net/npm/@maplat/core@latest/dist/maplat_core.js';
// ... usage
</script>Install via pnpm (recommended):
pnpm add @maplat/coreOr via npm:
npm install @maplat/coreMaplatCore strictly requires OpenLayers to function. Mapbox GL JS and MapLibre GL JS are optional extensions for vector tile support.
OpenLayers is architecturally required for MaplatCore. You must install it and import its CSS.
pnpm:
pnpm add olCDN:
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/ol@latest/ol.css" />
<script src="https://cdn.jsdelivr.net/npm/ol@latest/dist/ol.js"></script>Only required if you use Mapbox vector tiles.
pnpm:
pnpm add mapbox-glCDN:
<link href="https://api.tiles.mapbox.com/mapbox-gl-js/v1.6.1/mapbox-gl.css" rel="stylesheet" />
<script src="https://api.tiles.mapbox.com/mapbox-gl-js/v1.6.1/mapbox-gl.js"></script>Note: Mapbox GL JS requires an access token. Provide it via the mapboxToken option.
Only required if you use MapLibre vector tiles.
pnpm:
pnpm add maplibre-glCDN:
<link href="https://unpkg.com/maplibre-gl@latest/dist/maplibre-gl.css" rel="stylesheet" />
<script src="https://unpkg.com/maplibre-gl@latest/dist/maplibre-gl.js"></script><!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<!-- OpenLayers CSS is REQUIRED -->
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/ol@latest/ol.css" />
<!-- Optional: MapLibre GL JS -->
<link href="https://unpkg.com/maplibre-gl@latest/dist/maplibre-gl.css" rel="stylesheet" />
<script src="https://unpkg.com/maplibre-gl@latest/dist/maplibre-gl.js"></script>
</head>
<body>
<div id="map_div" style="width: 100%; height: 100vh;"></div>
<!-- OpenLayers JS is REQUIRED -->
<script src="https://cdn.jsdelivr.net/npm/ol@latest/dist/ol.js"></script>
<script type="module">
import { MaplatApp } from 'https://cdn.jsdelivr.net/npm/@maplat/core@latest/dist/maplat_core.js';
const option = {
maplibregl: maplibregl, // Inject only if you use it
// mapboxgl: mapboxgl,
// mapboxToken: 'YOUR_ACCESS_TOKEN',
startFrom: 'gsi', // Initial map ID
div: 'map_div' // Target div ID (optional, default is 'map_div')
};
MaplatApp.createObject(option).then(function(app){
console.log('Maplat initialized', app);
});
</script>
</body>
</html>import { MaplatApp } from '@maplat/core';
import 'ol/ol.css'; // REQUIRED: OpenLayers CSS
// Optional: Import MapLibre if needed
import maplibregl from 'maplibre-gl';
import 'maplibre-gl/dist/maplibre-gl.css';
const option = {
maplibregl: maplibregl, // Optional
startFrom: 'gsi',
};
MaplatApp.createObject(option).then((app) => {
console.log('Maplat initialized', app);
});currentMapInfo(): object- Get information about the currently active map.
mapInfo(mapID: string): object- Get information about a specific map by its ID.
changeMap(mapID: string, restore?: object): Promise<void>- Switch to a different map.
restoreobject can optionally set initial position (x, y, zoom, rotation).
- Switch to a different map.
requestUpdateState(data: object): Promise<void>- Request an update to the map state (position, transparency, etc.).
clientPointToLngLat(clientX: number, clientY: number): [number, number]- Convert screen coordinates (pixels relative to viewport) to Longitude/Latitude.
lngLatToClientPoint(lng: number, lat: number): [number, number]- Convert Longitude/Latitude to screen coordinates.
addMarker(data: object, clusterId?: string): void- Add a marker.
datashould containlng,lat,name,desc(description),icon, etc. clusterIdspecifies which layer to add the marker to (e.g., 'main', or specific map layer).
- Add a marker.
removeMarker(id: string): void- Remove a specific marker by its ID (e.g. 'main_1').
updateMarker(id: string, data: object, overwrite?: boolean): void- Update an existing marker's data (e.g. move position).
clearMarker(clusterId?: string): void- Remove all markers from a specific cluster/layer.
selectMarker(id: string): void- Programmatically select (highlight) a marker.
unselectMarker(): void- Deselect the currently selected marker.
getMarker(id: string): object- Get data for a specific marker.
setMarker(data: object): void- Batch add/set markers. Useful for initialization or mass updates.
showAllMarkers(): void- Make all markers visible.
hideAllMarkers(): void- Hide all markers.
addLine(data: object): void- Add a line feature. data:
{ lnglats: [[lng, lat], ...], stroke: { color: '#...', width: 2 } }
- Add a line feature. data:
addVector(data: object): void- Add a polygon/vector feature (GeoJSON compatible).
setLine(data: object): void/setVector(data: object): void- Batch set lines/vectors.
resetLine()/resetVector()/resetMarker()- Clear and reset basic lines/vectors/markers (often used for default layers).
clearLine()/clearVector()- Clear all lines/vectors.
Maplat manages markers in "layers".
addPoiLayer(id: string, data: object): void- Create a new POI layer.
datacan define default icons.
- Create a new POI layer.
showPoiLayer(id: string): void- Show a specific layer.
hidePoiLayer(id: string): void- Hide a specific layer.
listPoiLayers(hideOnly?: boolean, nonzero?: boolean): string[]- Get a list of available layer IDs.
handleGPS(enable: boolean): void- Turn GPS tracking on or off.
getGPSEnabled(): boolean- Check if GPS tracking is currently active.
setGPSMarker(position: object): void- Manually update the GPS marker position (usually handled automatically if GPS is on).
Use app.addEventListener(type, callback) to handle events.
clickMarker: Fired when a marker is clicked.evt.detailcontains marker data.clickMap: Fired when the map background is clicked.gps_result: Fired when a GPS position update happens.gps_error: Fired when GPS fails.
MaplatApp.createObject(option).then(function(app){
// Show current map info
console.log(app.currentMapInfo());
// Event Listener
app.addEventListener('clickMarker', function(evt) {
console.log('Marker clicked:', evt.detail);
app.selectMarker(evt.detail.namespaceID);
});
// Add a custom marker
app.addMarker({
lng: 141.1501111,
lat: 39.69994722,
name: "Morioka Castle",
desc: "Historical site in Morioka",
icon: "parts/blue_marker.png"
}, 'main'); // 'main' is the default layer
});# Run linting
pnpm run lint
# Run type checking
pnpm run typecheck
# Run unit tests
pnpm test
# Run E2E tests
pnpm run test:e2e# Build the library
pnpm run build
# Build development demo
pnpm run build:demo
# Run development server
pnpm run devCopyright (c) 2019-2026 Kohei Otsuka, Code for History
MaplatCore is under Maplat Limited License (based on Apache 2.0 with some restrictions). Please see LICENSE file for details.
