{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,23]],"date-time":"2026-01-23T11:56:30Z","timestamp":1769169390452,"version":"3.49.0"},"reference-count":50,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2016,7,23]],"date-time":"2016-07-23T00:00:00Z","timestamp":1469232000000},"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>Simplification of three-dimensional (3D) buildings is critical to improve the efficiency of visualizing urban environments while ensuring realistic urban scenes. Moreover, it underpins the construction of multi-scale 3D city models (3DCMs) which could be applied to study various urban issues. In this paper, we design a generic yet effective approach for simplifying 3D buildings. Instead of relying on both semantic information and geometric information, our approach is based solely on geometric information as many 3D buildings still do not include semantic information. In addition, it provides an integrated means to treat 3D buildings with either sloped or flat roofs. The two case studies, one exploring simplification of individual 3D buildings at varying levels of complexity while the other, investigating the multi-scale simplification of a cityscape, show the effectiveness of our approach.<\/jats:p>","DOI":"10.3390\/ijgi5080128","type":"journal-article","created":{"date-parts":[[2016,7,25]],"date-time":"2016-07-25T10:04:26Z","timestamp":1469441066000},"page":"128","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["An Integrated Simplification Approach for 3D Buildings with Sloped and Flat Roofs"],"prefix":"10.3390","volume":"5","author":[{"given":"Jinghan","family":"Xie","sequence":"first","affiliation":[{"name":"Department of Geography, National University of Singapore, Singapore 117570"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0410-714X","authenticated-orcid":false,"given":"Chen-Chieh","family":"Feng","sequence":"additional","affiliation":[{"name":"Department of Geography, National University of Singapore, Singapore 117570"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2016,7,23]]},"reference":[{"key":"ref_1","unstructured":"Wood, J., Kirschenbauer, S., D\u00f6llner, J., Lopes, A., and Bodum, L. 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