Patent attributes
A system, method and computer program product for efficiently generating on- and off-road travel routes using multi-resolution maps including a map generator (108), map database (106), route generator (100), heuristic generator (102), and search envelope factor generator (104). The map generator (108) converts input raster and vector map data into output multi-resolution raster map data suitable for routing and stores it in the map database (106). The route generator (100) uses the map database (106) to produce a route at a coarse zoom level and then regenerate the route at progressively higher zoom levels. The heuristic generator (102) penalizes high resolution routes that deviate too far from one or more low resolution routes. The search envelope factor generator (104) computes this penalty based on the distance from a given search graph node to the low resolution routes.
