Sketch Abstractions for Character Posing

Abstract
We propose a sketch-based posing system for rigged 3D characters that allows artists to create custom sketch abstractions on top of a character's actual shape. A sketch abstraction is composed of rigged curves that form an iconographic 2D representation of the character from a particular viewpoint. When provided with a new input sketch, our optimization system minimizes a nonlinear iterative closest point energy to find the rigging parameters that best align the character's sketch abstraction to the input sketch. A custom regularization term addresses the underconstrained nature of the problem to select favorable poses. Although our system supports arbitrary black-box rigs, we show how to optimize computations when rigging formulas and derivatives are available. We demonstrate our system's flexibility with examples showing different artist-designed sketch abstractions for both full body posing and the customization of individual components of a modular character. Finally, we show that simple sketch abstractions can be built on the fly by projecting a drawn curve onto the character's mesh. Redrawing the curve allows the user to dynamically pose the character. Taken together, our system enables a new form of intuitive sketch-based posing in which the character designer has the freedom to prescribe the sketch abstraction that is most meaningful for the character.
Description

        
@inproceedings{
10.1145:2786784.2786785
, booktitle = {
ACM/ Eurographics Symposium on Computer Animation
}, editor = {
Florence Bertails-Descoubes and Stelian Coros and Shinjiro Sueda
}, title = {{
Sketch Abstractions for Character Posing
}}, author = {
Hahn, Fabian
and
Mutzel, Frederik
and
Coros, Stelian
and
Thomaszewski, Bernhard
and
Nitti, Maurizio
and
Gross, Markus
and
Sumner, Robert W.
}, year = {
2015
}, publisher = {
ACM Siggraph
}, ISBN = {
978-1-4503-3496-9
}, DOI = {
10.1145/2786784.2786785
} }
Citation