利用公切圆弧生成光滑等距曲线算法研究

依据离散采样点生成等距平行曲线，在地理信息系统空间分析、计算机辅助设计以及遥感影像信息提取的后续处理研究中应用极为广泛。但当中心线拐角较小时，以往算法生成的平行曲线与实际情况差异较大，影响了处理结果的应用。在综合考虑双线目标的形状与特征后提出平行线与同心圆弧的公切算法，在保证生成的平行曲线严格等距的前提下，保持了曲线的光滑性。该算法很好地解决了双线目标的平行、等距、光滑三种特性的统一表达问题，实现了基于中心采样点的等距平行光滑曲线的自动生成。

Double-tangent arc algorithm for generation of offset parallel curve

Using discrete character points to generate offset parallel curve has been applied in many ways such as spatial analysis in geographic information system (GIS), computer-aided design (CAD) and processing of remote sensing image's information extraction. But when the turn angles are relatively smaller, the results will have diversity with the reality, which impacts the use of the algorithm. Considering the double-lines' figure and characteristics, double-tangent arc algorithm assuring the curve's equidistant offset and smoothness was put forward. The algorithm solves the unified expression of double-lines' parallel, equidistant offset and smoothness satisfactorily, and realizes offset parallel curve's auto-generation by using central sampling points.