US Patent 8681176 Rendering a map using style identifiers

A map server generates vector descriptors and corresponding style identifiers for rendering a map image. Each vector descriptor indicates a geometry of a respective map element in accordance with a vector graphics format, and each style identifier identifies a style according to which the corresponding map element is rendered. The map server then causes map data including the vector descriptors and the style identifiers to be transmitted to the client device via a communication network. When the map server receives a request for style data for modifying a map image at the client device, the map server generates a description of visual characteristics for one or more styles identified by the style identifiers included in the map data previously provided to the client device and causes the description of visual characteristics to be transmitted to the client device for applying to the vector descriptors at the client device.