加速的QTA地形可视化算法  

Accelerated QTA algorithm for terrain visualization

作　　者：罗健欣[1] 王柏[1] 冯钦[1] 倪桂强[1] 胡谷雨[1] 姜劲松[1] 端义峰[1] 

机构地区：[1]解放军理工大学指挥自动化学院,南京210007

出　　处：《计算机工程与应用》2012年第16期162-167,共6页Computer Engineering and Applications

基　　金：国家自然科学基金资助项目(No.60303023)

摘　　要：四叉树图集光线跟踪算法(QTA)是一种高效的平面地形可视化算法,在地形渲染相关的许多应用中(如矢量数据、谷地检测、等高线绘制等)都可以增加系统渲染速率。在QTA基础上,通过简化其中CRC算法的分支判断,引入新的屏幕误差控制策略,提出了一种新的光线投射地形可视化算法,同时对QTA中光栅化部分也进行了优化。该算法易于实现,且突破了原QTA算法只适用于平面地形的限制,算法实现了球形地形的可视化。实验结果验证了这一点,同时实验还显示,算法在不损失精度的情况下,具有更高的渲染速率。Quad-tree Atlas Ray Casting（QTA）algorithm is an efficient method for terrain visualization, which can be used in many application areas（e. g. vector data rendering, valley detection and contour line drawing）. This paper proposes, based on QTA, a novel algorithm by simplifying the branch determination of the CRC algorithm in QTA and introducing a new screen error tolerance strategy for terrain visualization. The algorithm proposed here also optimizes the rasterization part of QTA. The algorithm is easy to implement. It breaks through the limitation of only fitting for planar terrain of the original QTA algorithm, and extends it to spherical terrain. The experiments prove it and the experiments also show that this improved QTA algorithm has a high rendering rate without losing any precision.

关 键 词：光线投射 地形可视化 球形地形可视化 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]