webxtile (JS)

Browser client for the webxtile octree format. Read-only; designed for partial bbox loads and level-of-detail rendering in web applications.

The Python library writes a directory of msgpack tile files. This library reads those files over HTTP, caches them in IndexedDB, and returns flat typed arrays suitable for WebGL / point-cloud rendering.

Installation

npm install webxtile

Or install directly from the local source tree:

npm install ./deps/webxtile/js

Documentation

Full API reference with algorithms →

Quick start

import { WebxtileLoader } from "webxtile";

const loader = new WebxtileLoader("https://example.com/tiles");
await loader.open();   // fetches metadata.msgpack

// Load tiles at level 3 for a 2-D bounding box
const result = await loader.loadBBox([500000, 6200000, 520000, 6220000], 3);

// Iterate GPU-sized sub-tiles for rendering
for (const st of result.subTiles()) {
  // st.spatial_coords — { x: Float64Array, y: Float64Array, … }
  // st.variables      — { resistivity: Float32Array, … }
}

// Background: stream all leaf tiles (full resolution, whole dataset)
const ac = new AbortController();
for await (const tile of loader.streamLeaves({ signal: ac.signal })) {
  myTileCache.add(tile);
}

API summary

| Method / property | Description | |---|---| | new WebxtileLoader(baseUrl, [options]) | Create a loader for a tile directory. | | loader.open() | Fetch metadata.msgpack and open IndexedDB cache. Must be awaited first. | | loader.meta | Decoded metadata (spatial_dims, crs, var_meta, …). | | loader.loadBBox(bbox, level) | Load tiles intersecting bbox at octree depth level. | | loader.streamLeaves([options]) | Async generator — yields all leaf tiles in BFS order. Pauses while loadBBox is in flight. | | loader.clearCache() | Evict all tiles from in-memory cache and IndexedDB. | | result.subTiles() | Iterate GPU-sized sub-tiles; each has spatial_coords (1-D arrays) and variables (flat arrays). | | result.getCoord(dim) | Merged sorted coordinate values for one dimension across all tiles. |

See docs/api.md for full parameter descriptions, algorithms, and the concurrency/priority model.

Dependencies

| Package | Purpose | |---------|---------| | @msgpack/msgpack | msgpack decoding | | idb | Promise-based IndexedDB wrapper |