基于Beta样条曲线的等高线绘制研究

等高线须以相似的光滑曲线逼近实际地貌形态,并综合地形在一定限度内的地势起伏,其智能化控制对地貌表达具有重要的实用价值。绘图员绘制曲线时能凭经验捕捉到数据点所包含的几何形状信息,而张力样条函数和三次B样条曲线在节点插值时,严格要求二阶参数连续,不符合人的经验直觉,是节点对参数曲线连接光滑度的过分限制。根据人工绘制等高线的规则,提出将三次Beta样条曲线作为基于人工绘制约束的等高线插值的数学模型,通过引入形状控制参数放松对曲线的光滑性的要求,增加了控制等高线形状的自由度,把C2连续的三次B样条松弛成为G2连续的Beta样条,实验结果表明插值的等高线符合地形综合度要求。

Research on contours interpolation based on Beta spline

Contour must be similar to the smooth curves of approaching the actual landscape patterns,integrated the topographic relief and downs of the terrain,to the extent possible to show stereo sense.Draftsmen use their experience to capture the geometry information contained in data to map out reasonable contour;sum up hand-drawn contours' rules;make use of cubic Beta spline curve interpolation contours;introduce migration and tension shape Parameters to release the requirement to the smooth curves,reducing cubic...