Journal of the Korea Computer Graphics Society (한국컴퓨터그래픽스학회논문지)

Korea Computer Graphics Society (한국컴퓨터그래픽스학회)
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Computing Fast Secondary Skin Deformation of a 3D Character using GPU

GPU를 이용한 3차원 캐릭터의 빠른 2차 피부 변형 계산

  • Received : 2012.03.07
  • Accepted : 2012.05.21
  • Published : 2012.06.01
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Abstract

This paper presents a new method to represent the secondary deformation effect using simple mass-spring simulation on the vertex shader of the GPU. For each skin vertex of a 3D character, a zero-length spring is connected to a virtual vertex that is to be rendered. When a skin vertex changes its position and velocity according to the character motion, the position of the corresponding virtual vertex is computed by mass-spring simulation in parallel on the GPU. The proposed method represents the secondary deformation effect very fast that shows the material property of a character skin during the animation. Applying the proposed technique dynamically can represent squash-and-stretch and follow-through effects which have been frequently shown in the traditional 2D animation, within a very small amount of additional computation. The proposed method is applicable to represent elastic skin deformation of a virtual character in an interactive animation environment such as games.

본 논문에서는 GPU의 정점 셰이더에서 각 정점별 질량-스프링 모의 실험을 수행하여, 매우 빠른 속도로 피부의 2차 변형을 표현하는 새로운 방법을 제안한다. 3차원 캐릭터의 각 피부 정점에 대해, 길이가 0인 스프링으로 가상 정점을 연결하고, 캐릭터 동작에 따라서 피부 정점의 위치 및 속도가 변화하면, 질량-스프링 모의 실험을 통해 렌더링 될 가상 정점의 위치를 GPU의 정점 셰이더를 사용하여 병렬적으로 계산한다. 본 논문에서 제시하는 방법을 통해 피부의 재질 특성을 반영하는 2차 변형을 매우 빠르게 표현할 수 있으며, 각 피부 정점에 제안한 방법을 동적으로 적용하면 전통적인 2차원 애니메이션에서 관찰되는 수축-팽창(squash-and-stretch), 추종(follow-through)과 같은 효과도 매우 빠른 연산시간에 효과적으로 표현할 수 있다. 따라서 본 논문의 결과는 게임과 같은 실시간 응용분야에서 가상 캐릭터의 피부 변형을 표현하는데 효과적으로 사용될 수 있다.

Keywords

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