Techniques for rendering a scene are disclosed. In some embodiments, a scene definition is modified to generate a modified scene definition based at least in part on a current state of a local database at a device. The modified scene definition is constrained to include references to objects locally available in the local database, and at least one object referenced in the scene definition is substituted with a different object in the modified scene definition that is locally available in the local database. The scene is rendered at the device according to the modified scene definition.