三维虚拟人皮肤变形与塌陷部位的调整

SKIN DEFORMATION OF 3D VIRTUAL HUMAN AND ADJUSTMENT OF SUBSIDENCE AREA

针对线性混合蒙皮算法在虚拟人皮肤变形过程中容易产生皮肤塌陷的问题,在用该算法实现人体皮肤变形的基础上提出一种构造二次贝塞尔曲线的方法对塌陷部位进行调整。该方法首先根据模型自身的特点将模型分成不同的截面;其次,在塌陷部位的截面边缘上选取包括两端点在内的三个皮肤顶点来构造二次贝塞尔曲线,以两端点作为该曲线的两个控点,再反求出第三个控点,通过移动第三个控点到达预设点坐标位置以形成新的曲线;最后,在新的贝塞尔曲线上选取与初始塌陷部位截面相同数量的皮肤顶点作为构造皮肤模型的新数据点。实验结果表明,该方法在解决关节部位皮肤塌陷问题方面有显著的效果。

In order to solve the problem of skin collapsing easily happened in the process of virtual skin deformation performed by linear blend skinning algorithm, based on using that algorithm to achieve human body skin deformation, we propose a new method of constructing quadratic Bezier curves to adjust the subsidence area. This method first divides the model into different sections according to the characteristics of the model its own ; then it constructs a quadratic Bezier curve by selecting three skin vertices including two end points on the section edge of the subsidence area, that is, taking the two end points as two control points on the curve and computes inversely the third control point, by moving the third control point to the preset coordinate point the new Bezier curve can be formed. At last, on new Bezier curve it selects the skin vertices having the same numbers as the sections of initial subsidence area to be the new data points for building the skin model. Experimental results indicate that this method has distinct effect in solving the problem of skin subsidence at the joints.