Spain GP — April 26
Quadtrees are everywhere spatial data exists. Mapping services use quadtree-like tile pyramids to serve map tiles at different zoom levels (Bing's quadkey system, for example, addresses tiles as base-4 paths). Game engines use them for collision detection and visibility culling. Geographic information systems use spatial indexes to store and query spatial datasets. PostGIS uses GiST indexes (R-tree-style) for spatial queries on geometries, while PostgreSQL's core supports quadtree-like SP-GiST indexes for certain data types like points.
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Фото: Abdul Khaliq Achakzai / Reuters
百年党史峥嵘。中央党校内，立于广场上的一块巨石两面，“实事求是”“为人民服务”的箴言格外醒目，校园两侧，焦裕禄、谷文昌塑像静立，映照始终不渝的初心、不随境迁的追求、不为时易的坚持。