Update README.md

README.md

@@ -7,6 +7,28 @@ PMTiles is a single-file archive format for tiled data. A PMTiles archive can be
 See also:
 * [Cloud Optimized GeoTIFFs](https://www.cogeo.org)
 
+## How To Use
+
+Python library: `pip install pmtiles`
+
+    pmtiles-convert TILES.mbtiles TILES.pmtiles
+    pmtiles-convert TILES.pmtiles DIRECTORY
+    pmtiles-show TILES.pmtiles // see info about a PMTiles directory
+    pmtiles-serve TILES.pmtiles // start an HTTP server that decodes PMTiles into traditional Z/X/Y paths
+
+See https://github.com/protomaps/PMTiles/tree/master/python/bin for library usage
+
+JavaScript usage:
+
+Include the script:
+
+    <script src="https://unpkg.com/pmtiles@0.0.4/pmtiles.js"></script>
+
+Example of a raster PMTiles archive decoded and displayed in Leaflet:
+
+    const p = new pmtiles.PMTiles('osm_carto.pmtiles',{allow_200:true})
+    p.leafletLayer({attribution:'© <a href="https://openstreetmap.org">OpenStreetMap</a> contributors'}).addTo(map)
+    
 ## Specification
 
 A detailed specification is forthcoming. PMTiles is a binary serialization format designed for two main access patterns: over the network, via HTTP 1.1 Byte Serving (`Range:` requests), or via memory-mapped files on disk.
@@ -15,6 +37,7 @@ A detailed specification is forthcoming. PMTiles is a binary serialization forma
 * Directories are recursive, with a maximum of 21,845 entries per directory.
   * *21845 is the total tiles of a pyramid with 7 levels, or 1+4+16+64+256+1024+4096+16384*
 * Deduplication of tile data is handled by multiple entries pointing to the same offset in the archive.
+* The order of tile data in the archive is unspecified; an optimized implementation should arrange tiles on a 2D space-filling curve. 
 
 ### Details
 * The first 512 kilobytes of a PMTiles archive are reserved, and contain the headers as well as a root directory.