Visualizing 3D atmospheric data with spherical volume texture on virtual globes
作者:Liang, JM (Liang, Jianming)[ 1,2 ] ; Gong, JH (Gong, Jianhua)[ 1,3 ] ; Li, WH (Li, Wenhang)[ 1,3 ] ; Ibrahim, AN (Ibrahim, Abdoul Nasser)[ 1,3 ]
COMPUTERS & GEOSCIENCES
卷: 68  页: 81-91
DOI: 10.1016/j.cageo.2014.03.015
出版年: JUL 2014

摘要
Volumetric ray-casting is a widely used algorithm in volume visualization, but implementing this algorithm to render atmospheric volume data that cover a large area on virtual globes constitutes a challenging problem. Because atmospheric data are usually georeferenced to a spherical coordinate system described by longitude, latitude and altitude, adaptations to the conventional volumetric raycasting method are needed to accommodate spherical volume texture sampling. In this paper, we present a volumetric ray-casting framework to visualize atmospheric data that cover a broad but thin geographic area (because of the thinness of Earth's atmosphere). Volume texture conforming to the spherical coordinate system of a virtual globe can be created directly from the spherical volume data to avoid oversampling, undersampling or a loss of accuracy due to reprojecting and resampling such data into a Cartesian coordinate system. Considering the insignificant physical thickness of the atmosphere of the Earth, the ray-casting method presented in this paper also allows for real-time vertical scaling (exaggeration of the altitudinal range) without the need to re-process the volume texture, enabling convenient visual observation of the altitudinal variations. The spherical volume ray-casting method is implemented in a deferred rendering framework to integrate the volume effects into a virtual globe composed of a variety of background geospatial data objects, such as terrain, imagery, vector shapes and 3D geometric models. (C) 2014 Elsevier Ltd. All rights reserved.

通讯作者地址: Li, WH (通讯作者)
Chinese Acad Sci, Inst Remote Sensing & Digital Earth, State Key Lab Remote Sensing Sci, POB 9718, Beijing 100101, Peoples R China.
地址:
[ 1 ] Chinese Acad Sci, Inst Remote Sensing & Digital Earth, State Key Lab Remote Sensing Sci, Beijing 100101, Peoples R China
[ 2 ] Univ Chinese Acad Sci, Beijing 100049, Peoples R China
[ 3 ] Zhejiang CAS Applicat Ctr Geoinformat, Beijing 314100, Peoples R China