WebCAD中的剖面區(qū)域搜索算法

基于Web的CAD系統(tǒng)是協(xié)同設(shè)計研究的一個分支。論文討論了矢量化標記語言用于在Web上表示矢量圖形的優(yōu)點，比較了常見的幾種剖面區(qū)域搜索算法，提出了一種不依賴操作系統(tǒng)的剖面區(qū)域搜索的新算法。該算法提供四種可行的搜索方向，能搜索出包含一個給定種子點的唯一外部最小剖面區(qū)域和不包含該種子點的所有內(nèi)部非剖面區(qū)域，其計算復(fù)雜度與圖形尺寸無關(guān)。文中最后給出了此算法的應(yīng)用實例及計算性能。
關(guān)鍵詞 網(wǎng)頁CAD；矢量圖形；剖面區(qū)域；搜索
Abstract Web based CAD is a branch of the researches on collaborative design. This paper discusses the advantages of the vector markup language (VML) used to present vector graphics on Web, compares several types of finding algorithms for hatch region and proposes a new algorithm which is independent of operating systems for searching hatch region. The algorithm provides four feasible searching directions for searching an outer minimum hatch region which includes a given seed point and finding out all the internal non-hatch regions which exclude the seed point. The computing complexity of this algorithm is irrespective with the size of graphics. An application example of this algorithm and its computational performance are given at last.
Key words web CAD; vector graphics; hatch region; search