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We present a new framework for sketch-based modeling and animation of 3D organic shapes that can work entirely in an intuitive 2D domain, enabling a playful, casual experience. Unlike previous sketch-based tools, our approach does not require a tedious part-based multi-view workflow with the explicit specification of an animation rig. Instead, we combine 3D inflation with a novel rigidity-preserving, layered deformation model, ARAP-L, to produce a smooth 3D mesh that is immediately ready for animation. Moreover, the resulting model can be animated from a single viewpoint --- and without the need to handle unwanted inter-penetrations, as required by previous approaches. We demonstrate the benefit of our approach on a variety of examples produced by inexperienced users as well as professional animators. For less experienced users, our single-view approach offers a simpler modeling and animating experience than working in a 3D environment, while for professionals, it offers a quick and casual workspace for ideation., ACM Transactions on Graphics, 39 (6), ISSN:0730-0301, ISSN:1557-7368

Immersive media such as virtual and augmented reality pose some interesting new challenges for non-photorealistic animation: we must not only balance the screen-space rules of a 2D visual style against 3D motion coherence, but also account for stereo spatialization and interactive camera movement, at a rate of 90 frames per second. We introduce two new real-time rendering techniques: MetaTexture, an example-based texturing method that adheres to the movement of 3D geometry while preserving the texture’s screen-space characteristics, and Edge Breakup, a method for roughening edges by warping with structured noise. We also describe a custom rendering pipeline featuring art-directable coloring, shadow filtering, and texture indication, and our approach to animating and rendering a painterly ocean in real time. We show how we have used these techniques to achieve the “moving illustration” style of the real-time immersive short film “Age of Sail”.

We present a kinematic system for creating art-directed clothing and skin wrinkles on CG characters used in the production of computer-animated feature films. This system employs a curve-based method for generating wrinkles on reference poses, which are incorporated into a weighted matching algorithm that generates wrinkle deformations on an animated character. An artist creates wrinkle patterns in an interactive application that is intuitive to use and accommodates iterative art direction. The algorithm for evaluating wrinkles measures the local stress of a surface and creates weights that are used to interpolate between the reference wrinkle patterns during movement. We discuss various production pipeline issues, such as retargeting wrinkle patterns between different costumes and characters. We extend the approach to achieve believable age wrinkles for character skin. Our system has been used successfully in the production of feature-length animated films.