Adding dynamics to sketch-based character animations
Adding dynamics to sketch-based character animations
复制标题
为基于草图的角色动画添加动态
DOI：
10.2312/exp.20151176
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
Marie
中科院分区：
文献类型：
--
作者：
Martine Guay;Rémi Ronfard;Michael Gleicher;Marie
漫画家和动画师经常使用动作线来强调人物姿势的动态。在本文中，我们提出了一个基于物理的模型来模拟动作线的运动，从而从简单的绘图中获得丰富的运动。我们提出的方法分为三个步骤。基于用户提供的笔画，向前模拟二维弹性运动。为了确保关键帧之间的连续性，我们将前向模拟重新定位于绘制的笔画。最后，我们合成了一个与动态线匹配的三维人物运动。随着时间的推移，这条线可以像橡皮筋一样自由移动，这一事实引发了关于它与身体关系的新问题。绳子可能会移动得更快，把身体的某些部位甩在后面，或者绳子可能会慢慢地滑向身体的其他部位以获得支撑。我们推测，美工寻求最大限度地填充线条（用角色的身体），同时尊重基本的现实主义约束，如平衡。基于这些见解，我们提供了一种合成3D角色运动的方法，给定由用户在关键时刻指定的非连续约束身体部位。
Cartoonists and animators often use lines of action to emphasize dynamics in character poses. In this paper, we propose a physically-based model to simulate the line of action's motion, leading to rich motion from simple drawings. Our proposed method is decomposed into three steps. Based on user-provided strokes, we forward simulate 2D elastic motion. To ensure continuity across keyframes, we re-target the forward simulations to the drawn strokes. Finally, we synthesize a 3D character motion matching the dynamic line. The fact that the line can move freely like an elastic band raises new questions about its relationship to the body over time. The line may move faster and leave body parts behind, or the line may slide slowly towards other body parts for support. We conjecture that the artist seeks to maximize the filling of the line (with the character's body)---while respecting basic realism constraints such as balance. Based on these insights, we provide a method that synthesizes 3D character motion, given discontinuously constrained body parts that are specified by the user at key moments.