Displacement map技术在角色面部细节渲染中的研究与使用

Research and Application of Displacement Map Technology in Character Face Detail Rendering

Displacement map技术是将模型的顶点进行偏移,实现真实的面凹凸效果,能更好地在低精度模型上表现出高精度模型细节,最终达到所需的渲染效果。但由于Displacement map制作方法很多,在Maya arnold渲染器中使用Displacement map进行角色渲染时,经常不能控制渲染效果,导致角色过于肿胀或者面发生反转,尤其要在渲染中将同一角色的面部结构以及粗、较粗、细腻3种皮肤纹理细节有机结合表现出来,就更加困难。本文针对以上问题,提出了使用Maya中的ramp节点、plusMinusAverage节点、multiplyDivide节点,对Displacement map中包含3种皮肤纹理信息的RGB通道分别进行转换和控制的方法。并对该方法进行测试,证明方法的可行性。

Displacement map technique is to offset the vertices of the model to achieve a realistic face bump effect,which can better represent high precision model details on low precision models and finally achieve the desired rendering effect.However,due to the many methods of making Displacement map,the Maya arnold renderer often fails to control the rendering effect when using Displacement map for character rendering,resulting in the character being too swollen or the face being reversed.It is especially difficult to combine the same character’s facial structure and the three types of skin texture details:coarse,coarse and fine.In this paper,we propose a method to convert and control the RGB channels containing the three types of skin texture information in the displacement map by using the ramp node,plusMinusAverage node,and multiplyDivide node in Maya.And the method is tested to prove the feasibility of the method.