Restrict The Viewable Part Of A Tile To A Polygon Area In Leaflet?

In Leaflet, how does one restrict the viewable part of a tile to the area contained within a polygon (or geojson), i.e., the intersection between a polygon and the tile beneath. Ex

Solution 1:

Late reply, but for others looking, the Leaflet Boundary Canvas layer may do what you need. You can pass it a polygon or multipolygon, and it will obscure all other areas of the map.