华东师范大学学报（自然科学版） >

2024 , Vol. 2024 >Issue 2: 143 - 156

DOI: https://doi.org/10.3969/j.issn.1000-5641.2024.02.015

计算机科学

角色动画中基于隐式曲面的皮肤变形方法

  • 饶思敬 ,
  • 辛颖 ,
  • 潘俊君
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  • 1. 北京工业大学 信息学部, 北京　100124
    2. 北京航空航天大学 虚拟现实技术与系统全国重点实验室, 北京　100191

收稿日期: 2023-11-09

  网络出版日期: 2024-03-18

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Skinning in character animation based on implicit surface

  • Sijing RAO ,
  • Ying XIN ,
  • Junjun PAN
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  • 1. Faculty of Information Technology, Beijing University of Technology, Beijing　100124, China
    2. State Key Laboratory of Virtual Reality Technology and Systems, Beihang University, Beijing　100191, China

Received date: 2023-11-09

  Online published: 2024-03-18

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摘要

提出了一种角色动画中基于隐式曲面的皮肤变形方法, 主要面向具有骨骼层次以及相关蒙皮权重的动画模型, 利用隐式曲面来驱动皮肤变形. 首先, 采用埃尔米特径向基函数和泊松圆盘采样对给定骨骼绑定的网格部分进行重建, 把角色模型的体积近似当作一组局部的三维标量场, 并保留原有的网格属性; 其次, 构造场函数, 通过场函数纠正几何蒙皮技术的结果; 最后, 结合两种组合算子, 使用隐式方法在人体模型上形成合理可信的皮肤变形效果. 本方法不会产生糖纸扭曲和关节膨胀的问题, 并且可以生成皮肤接触效果和肌肉凸起. 由于该方法是后处理, 因此非常适合标准动画制作流程.

关键词： 隐式方法; 皮肤变形; 埃尔米特径向基函数; 泊松圆盘采样; 场函数

本文引用格式

饶思敬 , 辛颖 , 潘俊君 . 角色动画中基于隐式曲面的皮肤变形方法[J]. 华东师范大学学报（自然科学版）, 2024 , 2024(2) : 143 -156 . DOI: 10.3969/j.issn.1000-5641.2024.02.015

Abstract

This paper presents a method for skinning in character animation, utilizing implicit surfaces, which is designed to deform animated models with skeleton and associated skinning weights．This method reconstructs the mesh around a given skeleton with the Hermite radial basis function and Poisson-disk sampling on surfaces．This process transforms the character’s volume into a set of localized 3D scalar fields and preserves the original mesh properties．Field functions are then constructed and employed to refine the results obtained from the geometric skinning technique．The implicit method, combined with two types of combination operators, generates realistic skin deformations around the human skeleton model finally．The method does not cause candy twist and joint swelling problems, and can handle skin collision and muscle protrusions．Due to its post-processing feature, this method is very suitable for animation generation in standard production pipeline．

Key words： implicit method; skinning; Hermite radial basis function; Poisson-disk sampling; field function

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