1. A method of making computer games, the method comprising: selecting, by a game developer, from an inventory of map database products, a map database that contains data that represents a road network located in a real-world geographic area to be depicted as part of a playing scenario of a computer game, wherein the data that represents the road network includes geographic coordinates of positions of roads and turn restrictions at intersections of the roads, and wherein the map database products are provided by a map developer separate from the game developer; selecting, by the game developer, from a game shells inventory a game shell data structure that includes basic logic, rules, strategy, and characters for the computer game; combining, by the game developer, the map database and the game shell data structure in a computer game product; and providing the computer game product to an end user separate from the game developer and the map developer.