Overlay management system and method

摘要: An overlay management system and method in which an manager is invoked response to execution of original call a subroutine, the being at calling address. If subroutine not present executable portion memory, loads subroutine. The unloaded by event or according predetermined criteria for memory management. When initiated, determines address identity called. loaded into rewrites command directly memory. Once from restore call. In processing scenery data, data categorized content number different resolutions wherein each resolution represents geographic size. At resolution, visible types. stored reduced format so that item as type having location.