Computer-assisted rough 2D animation

• Melvin Even

• Univ. Bordeaux, CNRS, Bordeaux INP, Inria, LaBRI

Abstract

Traditional 2D animation is time-intensive process and requires significant expertise, as animators must hand-draw thousands of frames. While computer-based techniques like 3D animation or 2D puppet-style tools streamline this process, they often compromise the typical artistic style and workflows of traditional 2D. Existing computer-assisted methods automate inbetweening for clean line drawings but offer limited artistic control due to challenges with stroke matching and interpolation.

This thesis proposes a novel solution focused on rough sketches, using transient embeddings, i.e. temporary stroke groupings between keyframes, to generate rough inbetweens in real-time. This approach ensures smooth motion continuity and allows non-linear exploration of movement. Additionally, we tackle the complex task of representing 3D motion and occlusion in 2D by introducing a fast method for computing 2D masks and a system to dynamically manage stroke visibility. This enables artists to create 2D animations with realistic depth, including head turns, foreshortening, and overlapping volumes, without sacrificing flexibility or artistic control.

Video