1. A method of generating map tiles for a mapping application, the method comprising: receiving a request from a user device for a map tile at a particular zoom level; receiving a set of vectors, each vector representing a particular road segment in the map tile; rasterizing the set of vectors to identify a set of active pixels through which the vectors pass based on the particular zoom level; generating a connectivity byte mask that identifies a direction from which vectors enter a pixel for each active pixel in the connectivity byte mask; generating an undirected graph of vertices and edges connecting the vertices from the connectivity byte mask; reducing a number of the vertices within the undirected graph; creating a simplified map tile with less data than the map tile based on the reduced number of vertices; and transmitting the simplified map tile to the user device for rendering in the mapping application.