1. A non-transitory computer-readable medium storing computer-executable instructions that when executed by a computer cause: analyzing, by at least a processor, a boundary of a requested image to determine source images that collectively form an area that includes at least a portion of the requested image; generating, by at least the processor, a virtual grid from coordinates of each of the source images within the boundary by identifying edges of each of the source images from the coordinates to define rows and columns of the virtual grid within the boundary, and wherein the rows and columns of the virtual grid define virtual tiles in the virtual grid; creating, by at least the processor, a map that indicates which of the source images cover each of the virtual tiles; and generating, by at least the processor, the requested image as a mosaic of portions of the source images constructed based, at least in part, on the map.