Stylized keyframe animation of fluid simulations

Abstract

simulation 45 keyframe 50 in-between 53 in-between 57 keyframe 60 in-between 65 keyframe 70Figure 1: An upward-flowing jet of ink rendered in oil pastel. An underlying simulation is used as input to guide the artwork (frame 45 is shown). Frames 50, 60 and 70 are hand-drawn keyframes, while the remaining in-betweens were generated automatically by our system. AbstractWe present a method that combines hand-drawn artwork with fluid simulations to produce animated fluids in the visual style of the artwork. Given a fluid simulation and a set of keyframes rendered by the artist in any medium, our system produces a set of in-betweens that visually matches the style of the keyframes and roughly follows the motion from the underlying simulation. Our method leverages recent advances in patch-based regenerative morphing and image melding to produce temporally coherent sequences with visual fidelity to the target medium. Because direct application of these methods results in motion that is generally not fluid-like, we adapt them to produce motion closely matching that of the underlying simulation. The resulting animation is visually and temporally coherent, stylistically consistent with the given keyframes, and approximately matches the motion from the simulation. We demonstrate the method with animations in a variety of visual styles.

LazyFluids

“…[ Kwatra et al 2005] [Bénard et al 2013] [Browning et al 2014] our approach Figure 13: Results and comparison (see text for details): a single frame (No. 135) extracted from a longer sequence synthesized using [Kwatra et al 2005], [Bénard et al 2013], [Browning et al 2014], and our approach on five different exemplars of fluid elements (shown in the bottom right corner in each view).…”

“…They were recently applied to stylization of fluid simulations [Browning et al 2014] with compelling results. Nevertheless, a key drawback is that the user must prepare a set of keyframes that roughly match the appearance of the target flow at selected time steps.…”

“…Although such example-based workflow can considerably simplify the creation of fluid elements, we found that the current state of the art in flow-guided appearance transfer [Neyret 2003;Kwatra et al 2005;Bénard et al 2013;Browning et al 2014] does not solve (4), either producing disturbing temporal artifacts or failing to reproduce visual characteristics of real fluid elements.…”

A survey of the state-of-the-art in patch-based synthesis

“…Some early works explored these ideas for synthesizing 2D textures directly on 3D fluids [89,90]. More recently, patch-based fluid synthesis research has focused on stylizing and synthesizing fluid flows that match a target exemplar [91][92][93]. Ma et al [91] focused on synthesizing high-resolution motion fields that match an exemplar, while the low-resolution flow matches a simulation or other guidance field.…”

“…Ma et al [91] focused on synthesizing high-resolution motion fields that match an exemplar, while the low-resolution flow matches a simulation or other guidance field. Browning et al [92] synthesized stylized 2D fluid animations that match an artist's 16 Synthesis for 3D fabrication. Left: results from Martínez et al [87].…”