一种面向iOS系统的双缓冲改进算法及其应用

A modified double-buffering algorithm oriented to i OS and its application

为提高面向i OS(i Phone operating system)系统的矢量地图数据渲染效率,研究针对小尺寸屏幕的移动设备的矢量数据简化算法,以传统的Douglas-Peucker矢量简化算法和切分重组压缩法为基础,讨论结合屏幕像素、容忍时间等因素确定简化限值的方法.另外,基于对Quartz 2D引擎的渲染流程及双缓冲技术使用的效率问题的研究,提出改进的双缓冲渲染算法.实验结果显示,改进后的算法与传统算法相比,渲染效率有所提高.

In order to improve the rendering efficiency of i OS-oriented（ i Phone operating system）vector map,a method for determining the simplification limit for small-screen mobile devices is proposed through the thorough analysis of the simplification algorithm of vector data. On the basis of Douglas-Peucker algorithm we use this method to quantitatively calculate simplification limit,considering the factors of screen pixels and time tolerance. In addition,a modified algorithm is proposed for improving the efficiency of double buffering skill,on the basis of the study on rendering procedure and double buffering skill with Quartz 2D. The experimental results show that the modified alg orithm is more efficient than the traditional one.