{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,16]],"date-time":"2026-03-16T10:05:36Z","timestamp":1773655536678,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2018,8,11]],"date-time":"2018-08-11T00:00:00Z","timestamp":1533945600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key R&amp;D Program of China","award":["2017YFC0504003-4"],"award-info":[{"award-number":["2017YFC0504003-4"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41571332"],"award-info":[{"award-number":["41571332"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>To enhance the capability of three-dimensional (3D) radiative transfer models at the kilometer scale (km-scale), the radiosity applicable to porous individual objects (RAPID) model has been upgraded to RAPID3. The major innovation is that the homogeneous porous object concept (HOMOBJ) used for a tree crown scale is extended to a heterogeneous porous object (HETOBJ) for a forest plot scale. Correspondingly, the radiosity-graphics-combined method has been extended from HOMOBJ to HETOBJ, including the random dynamic projection algorithm, the updated modules of view factors, the single scattering estimation, the multiple scattering solutions, and the bidirectional reflectance factor (BRF) calculations. Five cases of the third radiation transfer model intercomparison (RAMI-3) have been used to verify RAPID3 by the RAMI-3 online checker. Seven scenes with different degrees of topography (valleys and hills) at 500 m size have also been simulated. Using a personal computer (CPU 2.5 GHz, memory 4 GB), the computation time of BRF at 500 m is only approximately 13 min per scene. The mean root mean square error is 0.015. RAPID3 simulated the enhanced contrast of BRF between backward and forward directions due to topography. RAPID3 has been integrated into the free RAPID platform, which should be very useful for the remote sensing community. In addition, the HETOBJ concept may also be useful for the speedup of ray tracing models.<\/jats:p>","DOI":"10.3390\/rs10081264","type":"journal-article","created":{"date-parts":[[2018,8,13]],"date-time":"2018-08-13T11:27:13Z","timestamp":1534159633000},"page":"1264","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Accelerated RAPID Model Using Heterogeneous Porous Objects"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9355-2338","authenticated-orcid":false,"given":"Huaguo","family":"Huang","sequence":"first","affiliation":[{"name":"Key Laboratory for Silviculture and Conservation, Ministry of Education, College of Forestry, Beijing Forestry University, Beijing100083, China"}]}],"member":"1968","published-online":{"date-parts":[[2018,8,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"255","DOI":"10.1016\/j.rse.2016.01.023","article-title":"A general method to normalize landsat reflectance data to nadir brdf adjusted reflectance","volume":"176","author":"Roy","year":"2016","journal-title":"Remote Sens. Environ."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1016\/S0034-4257(02)00091-3","article-title":"First operational brdf, albedo nadir reflectance products from modis","volume":"83","author":"Schaaf","year":"2002","journal-title":"Remote Sens. Environ."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"266","DOI":"10.1016\/j.rse.2012.11.021","article-title":"Comparison of methods for estimation of absolute vegetation and soil fractional cover using modis normalized brdf-adjusted reflectance data","volume":"130","author":"Okin","year":"2013","journal-title":"Remote Sens. Environ."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1879","DOI":"10.1890\/0012-9658(2003)084[1879:TLSSCA]2.0.CO;2","article-title":"Tree layer spatial structure can affect savanna production and water budget: Results of a 3-d model","volume":"84","author":"Simioni","year":"2003","journal-title":"Ecology"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Marshak, A., and Davis, A. (2005). 3D radiative transfer in vegetation canopies and cloud-vegetation interaction. 3D Radiative Transfer in Cloudy Atmospheres, Springer.","DOI":"10.1007\/3-540-28519-9"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"320","DOI":"10.1016\/S0034-4257(01)00282-6","article-title":"Recovery of forest canopy characteristics through inversion of a complex 3D model","volume":"79","author":"Kimes","year":"2002","journal-title":"Remote Sens. Environ."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"5469","DOI":"10.1109\/TGRS.2013.2289852","article-title":"Gost: A geometric-optical model for sloping terrains","volume":"52","author":"Fan","year":"2014","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"50","DOI":"10.1016\/j.rse.2018.02.001","article-title":"Capturing rapid land surface dynamics with collection V006 modis BRDF\/NBAR\/Albedo (MCD43) products","volume":"207","author":"Wang","year":"2018","journal-title":"Remote Sens. Environ."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1506","DOI":"10.1109\/JSTARS.2015.2416254","article-title":"Modeling land surface reflectance coupled BRDF for HJ-1\/CCD data of rugged terrain in Heihe river basin, China","volume":"8","author":"Wen","year":"2015","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Hao, D., Wen, J., Xiao, Q., Wu, S., Lin, X., Dou, B., You, D., and Tang, Y. (2018). Simulation and analysis of the topographic effects on snow-free albedo over rugged terrain. Remote Sens., 10.","DOI":"10.3390\/rs10020278"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1061","DOI":"10.1109\/36.921424","article-title":"Multiple-scattering scheme useful for geometric optical modeling","volume":"39","author":"Chen","year":"2001","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"323","DOI":"10.1016\/0168-1923(91)90069-3","article-title":"Modeling radiative transfer and photosynthesis in three-dimensional vegetation canopies","volume":"55","author":"Myneni","year":"1991","journal-title":"Agric. For. Meteorol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"4119","DOI":"10.1364\/AO.21.004119","article-title":"Radiative transfer model for heterogeneous 3-D scenes","volume":"21","author":"Kimes","year":"1982","journal-title":"Appl. Opt."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2640","DOI":"10.1109\/JSTARS.2017.2685528","article-title":"Dart: Recent advances in remote sensing data modeling with atmosphere, polarization, and chlorophyll fluorescence","volume":"10","author":"Lauret","year":"2017","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"493","DOI":"10.1109\/36.662732","article-title":"Raytran: A monte carlo ray-tracing model to compute light scattering in three-dimensional heterogeneous media","volume":"36","author":"Govaerts","year":"1998","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"221","DOI":"10.1016\/j.rse.2013.01.013","article-title":"Rapid: A radiosity applicable to porous individual objects for directional reflectance over complex vegetated scenes","volume":"132","author":"Huang","year":"2013","journal-title":"Remote Sens. Environ."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"705","DOI":"10.1109\/TGRS.1985.289389","article-title":"Geometric-optical modeling of a conifer forest canopy","volume":"GE-23","author":"Li","year":"2007","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1667","DOI":"10.3390\/rs70201667","article-title":"Discrete anisotropic radiative transfer (DART 5) for modeling airborne and satellite spectroradiometer and LIDAR acquisitions of natural and urban landscapes","volume":"7","author":"Yin","year":"2015","journal-title":"Remote Sens."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"418","DOI":"10.1016\/j.rse.2015.08.016","article-title":"The fourth phase of the radiative transfer model intercomparison (RAMI) exercise: Actual canopy scenarios and conformity testing","volume":"169","author":"Widlowski","year":"2015","journal-title":"Remote Sens. Environ."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.rse.2006.02.028","article-title":"Influence of woody elements of a norway spruce canopy on nadir reflectance simulated by the dart model at very high spatial resolution","volume":"112","author":"Malenovsky","year":"2008","journal-title":"Remote Sens. Environ."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1067","DOI":"10.1016\/j.rse.2009.01.017","article-title":"The structural and radiative consistency of three-dimensional tree reconstructions from terrestrial lidar","volume":"113","author":"Cote","year":"2009","journal-title":"Remote Sens. Environ."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"213","DOI":"10.1016\/j.rse.2013.03.030","article-title":"A new approach of direction discretization and oversampling for 3D anisotropic radiative transfer modeling","volume":"135","author":"Yin","year":"2013","journal-title":"Remote Sens. Environ."},{"key":"ref_23","unstructured":"Graziani, F. (2006). Rayspread: A virtual laboratory for rapid BRF simulations over 3-D plant canopies. Computational Methods in Transport: Granlibakken 2004, Springer."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"4834","DOI":"10.1109\/JSTARS.2017.2714423","article-title":"A large-scale emulation system for realistic three-dimensional (3-D) forest simulation","volume":"10","author":"Qi","year":"2017","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1016\/S0034-4257(00)00129-2","article-title":"3-D scene modeling of semidesert vegetation cover and its radiation regime","volume":"74","author":"Qin","year":"2000","journal-title":"Remote Sens. Environ."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"5421","DOI":"10.1080\/01431160903130911","article-title":"A realistic structure model for large-scale surface leaving radiance simulation of forest canopy and accuracy assessment","volume":"30","author":"Huang","year":"2009","journal-title":"Int. J. Remote Sens."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"20","DOI":"10.1186\/s40663-015-0044-5","article-title":"A 3D approach to reconstruct continuous optical images using Lidar and MODIS","volume":"2","author":"Huang","year":"2015","journal-title":"For. Ecosyst."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1007","DOI":"10.1080\/01431160701311291","article-title":"Improved topographic correction of forest image data using a 3-D canopy reflectance model in multiple forward mode","volume":"29","author":"Soenen","year":"2008","journal-title":"Int. J. Remote Sens."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"2148","DOI":"10.1109\/TGRS.2005.852480","article-title":"SCS+C: A modified sun-canopy-sensor topographic correction in forested terrain","volume":"43","author":"Soenen","year":"2005","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"5397","DOI":"10.1080\/01431160903130903","article-title":"Scale effect and scale correction of land-surface albedo in rugged terrain","volume":"30","author":"Wen","year":"2009","journal-title":"Int. J. Remote Sens."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Gao, B., Jia, L., and Menenti, M. (2013, January 21\u201326). An improved bidirectional reflectance distribution function (BRDF) over rugged terrain based on moderate spatial resolution remote sensing data. Proceedings of the Geoscience and Remote Sensing Symposium, Melbourne, Australia.","DOI":"10.1109\/IGARSS.2013.6723397"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"2900","DOI":"10.1109\/TGRS.2007.902272","article-title":"An extended 3-D radiosity\u2013graphics combined model for studying thermal-emission directionality of crop canopy","volume":"45","author":"Liu","year":"2007","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Huang, H. (2016, January 10\u201315). Rapid2: A 3D simulator supporting virtual remote sensing experiments. Proceedings of the IEEE Geoscience and Remote Sensing Symposium, Beijing, China.","DOI":"10.1109\/IGARSS.2016.7729942"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"916","DOI":"10.1109\/LGRS.2017.2687702","article-title":"Evaluation of atmospheric effects on land-surface directional reflectance with the coupled rapid and vlidort models","volume":"14","author":"Huang","year":"2017","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Huang, H., Xie, W., and Sun, H. (2015, January 26\u201331). Simulating 3D urban surface temperature distribution using ENVI-MET model: Case study on a forest park. Proceedings of the IEEE Geoscience and Remote Sensing Symposium, Milan, Italy.","DOI":"10.1109\/IGARSS.2015.7326100"},{"key":"ref_36","unstructured":"Huang, H. (2017, January 24\u201325). A unified radiosity model for optical and microwave regions. Proceedings of the Juhan Ross Legacy Symposium, Tartu, Estonia."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"S126","DOI":"10.5589\/m13-035","article-title":"Simulation of lidar waveforms with a time-dependent radiosity algorithm","volume":"39","author":"Huang","year":"2013","journal-title":"Can. J. Remote Sens."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"1958","DOI":"10.1109\/LGRS.2015.2440438","article-title":"Comparison of five slope correction methods for leaf area index estimation from hemispherical photography","volume":"12","author":"Cao","year":"2015","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"325","DOI":"10.1016\/j.rse.2018.03.030","article-title":"A modified version of the kernel-driven model for correcting the diffuse light of ground multi-angular measurements","volume":"210","author":"Dong","year":"2018","journal-title":"Remote Sens. Environ."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"234","DOI":"10.1109\/LGRS.2014.2333874","article-title":"Modeling directional brightness temperature over mixed scenes of continuous crop and road: A case study of the heihe river basin","volume":"12","author":"Cao","year":"2014","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"919","DOI":"10.1007\/s00468-011-0566-6","article-title":"Estimating leaf inclination and G-function from leveled digital camera photography in broadleaf canopies","volume":"25","author":"Pisek","year":"2011","journal-title":"Trees-Struct. Funct."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"260","DOI":"10.1016\/j.cag.2008.01.007","article-title":"Fast ray tracing and the potential effects on graphics and gaming courses","volume":"32","author":"Shirley","year":"2008","journal-title":"Comput. Graph."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"1144","DOI":"10.1016\/j.rse.2007.07.016","article-title":"The rami on-line model checker (ROMC): A web-based benchmarking facility for canopy reflectance models","volume":"112","author":"Widlowski","year":"2008","journal-title":"Remote Sens. Environ."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"3639","DOI":"10.1016\/j.rse.2008.05.014","article-title":"Canopy bidirectional reflectance calculation based on adding method and sail formalism: Addings\/addingsd","volume":"112","author":"Kallel","year":"2008","journal-title":"Remote Sens. Environ."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"218","DOI":"10.1007\/s003710050100","article-title":"A new antialiasing approach for image compositing","volume":"13","author":"Braquelaire","year":"1997","journal-title":"Vis. Comput."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/10\/8\/1264\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T15:18:08Z","timestamp":1760195888000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/10\/8\/1264"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,8,11]]},"references-count":45,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2018,8]]}},"alternative-id":["rs10081264"],"URL":"https:\/\/doi.org\/10.3390\/rs10081264","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,8,11]]}}}