@xtramaps/legend-symbols-maplibre

Framework-agnostic library for generating legend symbols from MapLibre GL styles. Takes a style layer and produces a plain virtual DOM tree ({ element, attributes, children }) that can be rendered by any framework.

Supports circle, line, fill, and symbol layer types.

Install

npm install @xtramaps/legend-symbols-maplibre

Usage

import { legendSymbol } from "@xtramaps/legend-symbols-maplibre";

const tree = legendSymbol({ zoom: 14, layer: myLayer, sprite: mySpriteData });

// tree is a plain object like:
// { element: "svg", attributes: { viewBox: "0 0 20 20", ... }, children: [...] }

Utilities

import {
  exprHandler,
  mapImageToDataURL,
  cache,
  loadImage,
  loadJson,
} from "@xtramaps/legend-symbols-maplibre";

• exprHandler({ zoom, properties }) - Evaluates MapLibre style expressions for a given zoom level and feature properties.
• mapImageToDataURL(map, icon) - Extracts an icon from a MapLibre map instance as a data URL.
• cache - Simple reference-counted cache for sprite data.
• loadImage(url, { transformRequest }) / loadJson(url, { transformRequest }) - Load sprite assets with optional request transformation.

License

MIT