一种刻线浮雕生成算法

An Algorithm for Generating Line-engraving Relief

刻线浮雕是一类将特征线条雕刻在基面上的浅浮雕,在产品铭牌、包装品、建筑装饰等领域有广泛应用.以物体的三维几何模型为输入,提出一种刻线浮雕的生成算法.首先提取三维模型在给定视线方向上可见部分和不可见部分交界处的轮廓点;然后计算各点与视线方向相关的曲率值大小,并通过阈值设定对模型上的可用于浮雕效果的凹陷部分的特征点集进行提取;将膨胀和腐蚀这两种形态学操作运用在三角网格上,实现特征点集的优化,并对已有的腐蚀操作结构进行改进,避免孔洞的产生;最后给定特征点集的雕刻深度,就可获得刻线浮雕效果.实例证明,本文算法生成的浮雕具有很好的视觉效果.

Line-engraving relief is a kind of Bas-relief with line contours incised on a background surface.It is widely used in such application areas as sign-making,packaging,and architecture decorating.In this paper,an algorithm for generating line-engraving relief from 3D triangular mesh is proposed.Firstly,the silhouette points are extracted at the border where the surface turns away from the viewer and becomes invisible.Then the radial curvature,which is defined as the normal curvature in the direction of the view vector projected onto the tangent plane,is calculated for every vertex.By setting a threshold for the radial curvature,we collect the concave feature points,which are visually regarded as engraving reliefs.Then the dilation and erosion operators,the two basic morphological operators in image processing,are adopted to do the optimization process.Finally,line-engraving relief is produced by setting the cutting depth for the feature points.The experiments demonstrate the relief has good visualization effect.