摘要
海量数字高程模型的可视化在地理信息系统、三维导航以及军事仿真等应用领域扮演着重要的角色。提出了一种大规模外存地表模型可视化方法,该方法由预处理和实时处理2个阶段组成。在预处理阶段,对原始地形数据进行分块处理,为减少外存空间开销,提出了一种新的块内数据存储方法,仅存储各层新增顶点,使冗余数据显著减少。实时处理阶段,通过引入与视线相关的屏幕误差计算方法减少绘制数据量,同时采用一种基于扩展视锥的预测策略,实现了外存数据的实时调度。实验表明,与传统方法相比该方法外存开销减少了60%以上,平均绘制速度超过了30帧/秒。
Visualization of mass digital elevation models plays an important role in a number of application domains,such as GIS,3D navigation and military simulation.A method for the visualization of out-of-core terrain model is proposed.The method consists of two stages.In preprocessing stage,the full resolution terrain datasets are partitioned into a set of uniform blocks.In order to save the space of hard disk,a novel data storage method in block is presented,which only stores the newly added vertices in each level and reduces the redundant data.In real-time processing stage,the decrease of data quantity is achieved by using sight-line-dependent screen error computation method.Based on a view frustum extension prefetching scheme,the real-time loading of the datasets is also implemented.Experiments show that compared with traditional methods,our method has reduced the external memory cost by 60%;and the average rendering speed is higher than 30fps.
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
2011年第10期2309-2315,共7页
Chinese Journal of Scientific Instrument
基金
国家863计划(2007AA010407)
航空基金项目(20080580005)资助
关键词
四叉树
多分辨率模型
细节层次
实时绘制
模型误差
quadtree
multi-resolution model
level of detail
real-time rendering
model error
