Building hyperlocal GrabMaps

This post details the process of integrating hyperlocal data into GrabMaps, focusing on road network attributes. It describes downloading and converting OpenStreetMap .pbf files to Parquet format using a Parquetizer. The identification of hyperlocal data involves applying customized rules defined by local map teams, combined with data from GPS pings and KartaView. A specific example of intersection link identification is provided, explaining the use of Spark, geohash, and graph computations to determine when road segments meet specific criteria (parallel, same name, one-way, angle/shape). The impact is demonstrated through improved routing efficiency in GrabNav.