基于像素的椭圆窗口裁剪算法  

Ellipse clipping algorithm based on pixel

作　　者：唐棣[1] 阎晓敏[1] 孙岩[1] 

机构地区：[1]辽宁师范大学计算机与信息技术学院,辽宁大连116029

出　　处：《计算机工程与设计》2008年第22期5898-5900,共3页Computer Engineering and Design

基　　金：国家自然科学基金项目(20633050)

摘　　要：现有的椭圆窗口裁剪算法需通过求交运算确定裁剪对象,算法复杂,而且只适用于简单图形的裁剪。由于裁剪是计算机图形学中基础算法之一,因此找到一种高效的椭圆窗口裁剪算法具有重要的实际意义。提出了一种基于像素的椭圆窗口裁剪算法,首先采用高效的椭圆算法生成裁剪窗口,然后以窗口作为边界利用扫描线原理确定窗口内像素并输出,完成裁剪过程。该方法无需复杂的求交运算,只需简单的像素读写便可完成裁剪操作,因此裁剪过程简单,执行速度快,算法复杂度低,尤其适合于复杂图形及图像的裁剪处理。Existing ellipse clipping algorithms determine clipping objects through complicated steps of calculating cross-points which is complex and only suitable for simple graphics clipping. Because dipping is one of basis algorithms in computer graphics, it is necessary to find out a high-efficiency clipping algorithm based on ellipse window. A new clipping algorithm based on ellipse window is proposed, which can efficiently clip arbitrary graphics and images. Firstly, a clipping window is generated through a high-quality ellipse algorithm. Then, pixels in the window is scanned and output through scan-line principle. At last, clipping process is finished. The method has advantages of simple design, fast implementation and low complieacy which is more suitable for clipping complicated graphics and image.

关 键 词：椭圆窗口 裁剪 像素 光栅图形学 四分对称性 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]