{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T17:21:30Z","timestamp":1777656090845,"version":"3.51.4"},"reference-count":34,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2016,9,9]],"date-time":"2016-09-09T00:00:00Z","timestamp":1473379200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002446","name":"Catholic University of Pusan","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100002446","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>This study proposes a modeling method that can effectively generate multiple diverse digital trees for creating immersive virtual landscape based on virtual reality and an optimization method for real-time rendering. The proposed method simplifies a process of procedures from growth of tree models to the generation of the three-dimensional branch geometric model. Here, the procedural branch graph (PBG) algorithm is proposed, which simultaneously and effectively generates diverse trees that have a similar branch pattern. Moreover, the optimization method is designed in a polygon-based branch model which controls the resolution of tree models according to the distance from the camera to generate a tree model structure that is appropriate for an immersive system based on virtual reality. Finally, a virtual reality system is established based on the Oculus SDK (Software Development Kit) and Unity3D engine. In this process, the image processing-based pixel to tree (PTT) method is proposed as a technique for easily and efficiently generating a virtual landscape by allocating multiple trees on terrain. An immersive virtual landscape that has a stereoscopic perception and spatial impression is created through the proposed method and whether it can deliver experience of nature in virtual reality to the users was checked through an experiment.<\/jats:p>","DOI":"10.3390\/sym8090093","type":"journal-article","created":{"date-parts":[[2016,9,9]],"date-time":"2016-09-09T10:36:06Z","timestamp":1473417366000},"page":"93","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Modeling and Optimization of a Tree Based on Virtual Reality for Immersive Virtual Landscape Generation"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1663-9306","authenticated-orcid":false,"given":"Jinmo","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Software, Catholic University of Pusanm, Busan 46252, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2016,9,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Sutherland, I.E. 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