大规模外存场景的交互绘制

在场景分割的基础上,提出一种连续分层层次细节模型组织场景,并对视点空间进行划分,为每个视点单元计算恰好满足单元内任意视点屏幕像素误差的场景图节点列表,称为cell-front;然后利用cell-front对外存模型的存储进行重新设计.在绘制时采用多线程技术,绘制线程对当前cell-front进行可见性剔除和视点相关的选择绘制;预取线程采用一种基于视点单元的预取策略,利用视点单元之间cell-front的变化控制预取数据的调度.该算法能够在保证场景绘制质量的前提下,在普通的PC机上实现大规模外存场景的实时交互显示.

Interactive Out-of-Core Rendering for Large-Scale Complex Environments

This paper presents a novel method for representing a scene with continuous hierarchical levels of detail,and organizing the scene into sub-regions according to the view points by what is called cell-front.A cell-front is a scene graph node list that can rightly meet the screen space error bound within a view region.Then the disk layout of the out-of-core geometry model is redesigned.In run-time,the multi-threaded technique is used.The rendering thread constructs the cell-front for the current view cell and renders the geometries through visibility culling and view-dependent refinement.The prefetch thread employs a region-based prefetch strategy,to control the data prefetch based on the difference between neighboring cells' cell-front.The algorithm can perform interactive out-of-core rendering for large-scale complex environments on commodity PC with fine image quality.