| 摘要 |
<p>Disclosed herein is a method and apparatus for use in searching a geographic database to retrieve geographic objects one cell from a neighborhood of cells at a time. A cell neighborhood can be defined using a grid of cells and an initial, or center, point. A first neighborhood is identified based on its proximity to the initial search point, and corresponds to a first geographic area defined using the initial point and a distance from the initial search point in a number of directions. In a case that more than one cell neighborhood is used, each subsequent cell neighborhood is defined so that it excludes cells belonging to a previously-searched cell neighborhood. A subsequent neighborhood corresponds to a geographic area that is a distance from the initial point greater than the distance associated with a previously-searched neighborhood.</p> |
