Publisher's Synopsis
The present invention discloses a device and method for controlling zooming-in of an electronic map, a device and method for controlling zooming-out of an electronic map, a device and method for controlling panning of an electronic map, a device and method for computing tiles within a visual region of an electronic map, and a device and method for processing an electronic map tile request queue, wherein the method for controlling zooming-in of an electronic map comprises: determining a target display level to be reached via zooming in when receiving an instruction of zooming in the map, and searching out a plurality of target tiles that need to be displayed in the target display level; selecting a pre-loaded display level based on a relationship between a current display level and the target display level, and searching out pre-loaded tiles corresponding to the target tiles in the pre-loaded display level; acquiring the pre-loaded tiles and the target tiles according to an order of priority, loading and displaying the pre-loaded tiles by zooming in according to a level difference between the pre-loaded display level and the target display level; and after acquiring the target tiles, loading and displaying the target tiles so as to replace the zoomed-in pre-loaded tiles at corresponding positions.
