MING OUHYOUNGLiang, R.-H.R.-H.LiangYUNG-YU CHUANG2018-09-102018-09-10199601677055http://www.scopus.com/inward/record.url?eid=2-s2.0-0030244674&partnerID=MN8TOARShttp://scholars.lib.ntu.edu.tw/handle/123456789/323020Because of the view independence and photo realistic image generation in a diffuse environment, radiosity is suitable for an interactive walkthrough system. The drawback of radiosity is that it is time-consuming in form factor estimation, and furthermore, inserting, deleting or moving an object makes the whole costly rendering process repeat itself. To solve this problem, we encapsulate necessary information for form factor calculation and visibility estimation in each object, which is called a reusable radiosity object. An object is defined as a cluster or clusters of triangles. Whenever a scene updates, the radiosity algorithm looks up the prestored information in each object, thus speeding itself up by two orders of magnitude. Besides, solution time based on cluster representatives is linear to the number of objects since each object is reusable, encapsulated with preprocessed data in every level of hierarchy. We also analyze the unregarded error on visibility estimation and propose a statistically optimal adaptive algorithm to maintain the same error for each link.Anisotropic visibility; Clustering; Hierarchical radiosity; Visibility errorAdaptive algorithms; Calculations; Computational geometry; Data processing; Error analysis; Estimation; Optimization; Statistical methods; Visibility; Clustering; Form factor calculation; Hierarchical radiosity; Photo realistic image generation; Rendering; Reusable radiosity objects; Interactive computer graphicsjournal article10.1111/1467-8659.15303472-s2.0-0030244674