Curly-Cue: Geometric Methods for Highly Coiled Hair
The first paper on afro-textured hair to be accepted to SIGGRAPH since the conference was first held in 1974. Featuring Type 4 hair simulated at a variety of lengths, this groundbreaking paper demonstrates our latest breakthroughs in the development of unique coily hair algorithms.
| Abstract: We present geometric methods for generating shapes that are characteristic of highly coiled hair. Different features become visually relevant when hairs are well-approximated by high-frequency helices instead of low-frequency curves, so we present algorithms for three such phenomena. First, a Fourier-based method for phase locking, the process by which disparate helices near the scalp coalesce into a single curl. Second, a method for period skipping which models individual helices deviating from the coalesced curl. Third, a non-linear optimization that directly generates the shapes of switchbacks, a.k.a. helical perversions, which heretofore could only be produced through direct physical simulation. By applying all three methods in tandem, we show that we can achieve richly detailed depictions of highly coiled hair. |
| Read more at https://www.cs.yale.edu/homes/wu-haomiao/publication/curlyCue.html |
More Than Killmonger Locs: A Style Guide to Black Hair (in Computer Graphics)
Featuring presentations by OSAHL Director Prof. A.M. Darke, Dr. Ted Kim, and graphic artist Isaac Olander at SIGGRAPH 2024. The course focused on the state of curly hair research in computer graphics, as well as presented different methodologies for closing the gap between straight and coily hairstyles.
| Abstract: We will cover recent advances and ongoing challenges in the depiction of Black hair, otherwise known as kinky, or Afro-textured hair. In computer graphics, the majority of hair research has been in the depiction straight or wavy hair. As a result, many aspects of the aesthetics and mechanics of Black hair remain poorly understood. To help fill this gap, we will present Code My Crown, a free guide to creating Black digital hairstyles that we co-authored in collaboration with a community of game artists and Dove. We also cover styling guidelines for 3D models in the Open Source Afro Hair Library, and present Lifted Curls, our strand simulation technique specifically designed for Afro-textured hair. Finally, we will suggest future directions for hair research. |
Lifted Curls: A Model for Tightly Coiled Hair Simulation
Details our foray into the simulation of afro-textured hair. Most closely resembling the characteristics of Type 3c or curly-kinky hair, Lifted Curls brings us one step closer to the authentic simulation of the the curliest hair types. Read the paper and watch the simulations at tkim.graphics. Winner of the prestigious Best Paper Award at the Symposium on Computer Animation (SCA) 2023.
| Abstract: We present an isotropic, hyperelastic model specifically designed for the efficient simulation of tightly coiled hairs whose curl radii approach 5 mm. Our model is robust to large bends and torsions, even when they appear at the scale of the strand discretization. The terms of our model are consistently quadratic with respect to their primary variables, do not require per-edge frames or any parallel transport operators, and can efficiently take large timesteps on the order of 1/30 of a second. Additionally, we show that it is possible to obtain fast, closed-form eigensystems for all the terms in the energy. Our eigenanalysis is sufficiently generic that it generalizes to other models. Our entirely vertex-based formulation integrates naturally with existing finite element codes, and we demonstrate its efficiency and robustness in a variety of scenarios. | ||||
| Read more at https://www.tkim.graphics/LIFTED/ |