基于草图交互的个性化服装生成方法

Individuality Based Garment Surface Modeling Through a 3D Interactive Sketch

以建立和交互修改三维服装草图为设计手段,提出在三维人体模型上生成三维个性化服装的参数化造型方法.服装草图由2种基本几何元素组成:体现人体围度信息的封闭样条曲线和体现人体在高度方向上曲面形状过渡的不封闭样条曲线.将服装草图约束分为2类4种:一类是体现服装宽松程度的人体与服装曲面之间的间隙约束;另一类是服装几何元素本身之间的共点、共面与对称约束.从人体的特征点出发,通过间隙约束生成服装草图的几何元素;在共点、对称和共面约束下,由服装草图几何元素建立拓扑结构为四边网格的服装草图.服装草图的交互修改是草图约束维护的过程,构建侧视图、正视图、断面图3个视图组成草图修改平台,在平台上交互编辑特征曲线.服装曲面则以三维草图为框架,通过对四边网格双线性Coons曲面插值生成.提供的设计方法使服装的造型变得简洁、灵活.

This paper presents a new method for 3D garment parameterized modeling. Based on a 3D human body, a garment surface can be generated directly using sketch. Two types of splines are used to serve as geometric elements of a 3D garment sketch： closed feature splines reflecting the transverse contour information of a garment surface and open feature splines reflecting the lengthwise contour information of a garment surface. Constraints for a 3D garment sketch are divided into two catalogs and four types. The first catalog is of space constraints reflecting the gap between a garment surface and a 3D human model; the second catalog is of constraints among geometric elements, which include common control point constraint, coplanarity constraint and symmetry constraint. Based on predefined feature points of a 3D human model, geometric elements of a 3D garment sketch are created using the first catalog of constraints. Under the second catalog of constraints, a 3D garment surface represented by a quadrangular mesh is built automatically. The interactive modification for a 3D garment sketch can be considered as the process of constraints maintenance. By using an interactive platform composed of side view, front view and perspective view, and editing feature lines on this platform, a 3D garment sketch is intuitively modified. A garment surface is created by interpolating the quadrangular mesh of a garment sketch with Coons surfaces. The proposed method makes garment surface modeling easy and flexible.