{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T17:53:57Z","timestamp":1778781237790,"version":"3.51.4"},"reference-count":32,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,9,25]],"date-time":"2021-09-25T00:00:00Z","timestamp":1632528000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJGI"],"abstract":"<jats:p>Oblique photogrammetry models are indispensable for implementing digital twins of cities. Geographic information system researchers have proposed plenty of methods to load and visualize these city-scaled scenes. However, when the area viewed changes quickly in real-time rendering, current methods still require excessive GPU calculation and memory occupation. In this study, we propose a data organization method in which we merged all quadtrees and used a binary encoding method to encode nodes in a merged tree so that the parent\u2013child relationship between the tree nodes could be calculated using rapid binary operations. After that, we developed a strategy to cancel the loading of redundant nodes based on the parent\u2013child relationship, which helped to reduce the hard disk loading time and the amount of memory occupied in visualization. Moreover, we introduced a parameter to measure the area of the triangle mesh per pixel to achieve unified data scheduling under different production standards. We implemented our method based on Unreal Engine (UE), and three experiments were designed to illustrate the advantages of our methods in index acceleration, frame time, and memory reduction. The results show that our methods can significantly improve visualization fluency and reduce memory usage.<\/jats:p>","DOI":"10.3390\/ijgi10100643","type":"journal-article","created":{"date-parts":[[2021,9,27]],"date-time":"2021-09-27T04:55:33Z","timestamp":1632718533000},"page":"643","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Efficient Visualization of Large-Scale Oblique Photogrammetry Models in Unreal Engine"],"prefix":"10.3390","volume":"10","author":[{"given":"Yuhao","family":"Huo","sequence":"first","affiliation":[{"name":"College of Electronic Science, National University of Defense Technology, Changsha 410073, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anran","family":"Yang","sequence":"additional","affiliation":[{"name":"College of Electronic Science, National University of Defense Technology, Changsha 410073, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qingren","family":"Jia","sequence":"additional","affiliation":[{"name":"College of Electronic Science, National University of Defense Technology, Changsha 410073, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yebin","family":"Chen","sequence":"additional","affiliation":[{"name":"Research Institute of Smart City, School of Architecture and Urban Planning, Shenzhen University, Shenzhen 518060, China"},{"name":"School of Resource and Environmental Sciences, Wuhan University, Wuhan 430072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Biao","family":"He","sequence":"additional","affiliation":[{"name":"Research Institute of Smart City, School of Architecture and Urban Planning, Shenzhen University, Shenzhen 518060, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jun","family":"Li","sequence":"additional","affiliation":[{"name":"College of Electronic Science, National University of Defense Technology, Changsha 410073, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,25]]},"reference":[{"key":"ref_1","first-page":"1","article-title":"Digital Twin: Manufacturing Excellence through Virtual Factory Replication","volume":"1","author":"Grieves","year":"2014","journal-title":"White Pap."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"41","DOI":"10.5194\/isprsannals-II-4-41-2014","article-title":"Study on the Construction and Application of 3D Geographic Information Services for the Smart City","volume":"2","author":"Mao","year":"2014","journal-title":"ISPRS Ann. 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