Abstract
Animating an articulated character requires the explicit specification of interior skeleton structure and its attachment to skin surface. This task of “rigging” typically involves the manual weight painting and deformation fine-tuning with popular conventional animation methods. Weight painting is unavoidably a time-consuming and laborious process that would need sophisticated skills from animators during animation production. In this paper, using the extended position-based dynamics (PBD), we have articulated a strategy to generate the realistic skin deformation and reuse the painted weights on a new character. For each frame, the skin is deformed by the linear blend skinning method (LBS) at first. To solve the problem of candy-wrapper effect and surface overlapping in LBS, we improve the traditional PBD method by adding energy constraints and employ several geometrically and physically-based constraints to refine the deformed skin automatically. To further reduce the animator’s workload from tedious rigging process, we propose the weight retargeting approach using surface matching and interpolation based on the powerful bi-harmonic distance. It could transfer the weights of an existing model to a new character with similar topology. Through numerous experiments, we could demonstrate the visual performance of our new techniques on a variety of articulated characters.
Similar content being viewed by others
References
Hiebert, B., Dave, J., Kim, TY., et al.: The Chronicles of Narnia: the lion, the crowds and rhythm and hues author video presentations are available from the citation page. In: ACM SIGGRAPH 2006 Courses, ACM, New York (2006)
Smith, J., White, J.: BlockParty: modular rigging encoded in a geometric volume. Acm Trans. Gr. 25, 115 (2006)
Pan, J., Yang, X., Xie, X., et al.: Automatic rigging for animation characters with 3D silhouette. Comput. Anim. Virtual Worlds 20(2–3), 121–131 (2009)
Baran, I., Popović, J.: Automatic rigging and animation of 3D characters. Acm Trans. Gr. 26(3), 72 (2007)
Jacobson, A., Baran, I., Popović, J., et al.: Bounded biharmonic weights for real-time deformation. Acm Trans. Gr. 30(4), 76–79 (2011)
Dionne, O., Lasa, MD.: Geodesic voxel binding for production character meshes. In: Proceedings of the 12th ACM SIGGRAPH/Eurographics Symposium on Computer Animation ACM, New York, 173–180 (2013)
Magnenat-Thalmann, N., Laperrière, R., et al.: Joint-dependent local deformations for hand animation and object grasping. Proc. Gr. Interface 26–33, (1988)
Forstmann, S., Ohya, J.: Fast skeletal animation by skinned arc-spline based deformation. In: Fellner, D., Hansen, C. (eds.) Proceedings in EG Short Papers, The Eurographics Association. doi:10.2312/egs.20061014 (2006)
Mukai, T., Kuriyama, S.: Efficient dynamic skinning with low-rank helper bone controllers. Acm Trans. Gr. 35(4), (2016)
Kavan, L., Collins, S., Zra, J., et al.: Geometric skinning with approximate dual quaternion blending. Acm Trans. Gr. 27(4), 995–999 (2008)
Kim, Y.B., Han, J.H.: Bulging-free dual quaternion skinning. Comput. anim. virtual worlds 25(3–4), 321–329 (2014)
Vaillant, R., Barthe, L., Guennebaud, G., et al.: Implicit skinning: real-time skin deformation with contact modeling. Acm Trans. Gr. 32(4), 96–96 (2013)
Vaillant, R., Guennebaud, G., Barthe, L., et al.: Robust iso-surface tracking for interactive character skinning[J]. Acm Trans. Gr. 33(6), 189 (2014)
Müller, M., Chentanez, N.: Adding physics to animated characters with oriented particles, the workshop on virtual reality interactions and physical simulations. Vriphys 2011, Lyon, France, DBLP 83-91, (2011)
James, D.L., Twigg, C.D.: Skinning mesh animations. Acm Trans. Gr. 24(3), 399–407 (2005)
Park, S.I., Hodgins, J.K.: Data-driven modeling of skin and muscle deformation. Acm Trans. Gr. 27(3), 15–19 (2008)
Lewis, J.P., Cordner, M., Fong, N.: Pose space deformation: a unified approach to shape interpolation and skeleton-driven deformation. Conf. Comput. Gr. Interact. Tech. 165–172, (2000)
Xu, H., Barbič, J.: Pose-space subspace dynamics. Acm Trans. Gr. 35(4), 1–14 (2016)
Mohr, A., Gleicher, M.: Building efficient, accurate character skins from examples. Acm Trans. Gr. 21(3), 562–568 (2003)
Merry, B., Marais, P., Gain, J.: Animation space: a truly linear framework for character animation. Acm Trans. Gr. 25(4), 1400–1423 (2006)
Seo, J., Seol, Y., Wi, D., et al.: Rigging transfer. Comput. Anim. Virtual Worlds 21(3–4), 375–386 (2010)
Ju, T., Zhou, Q.Y., Panne, M., et al.: Reusable skinning templates using cage-based deformations. Acm Trans. Gr. 27(5), 32–39 (2008)
Le, B.H., Hodgins, J.K.: Real-time skeletal skinning with optimized centers of rotation. Acm Trans. Gr. 35(4), 1–10 (2016)
Allen, B., Curless, B., Popović, J., et al.: The space of human body shapes: reconstruction and parameterization from range scans[J]. Acm Trans. Gr. 22(3), 587–594 (2003)
Ali-Hamadi, D., Liu, T., Gilles, B., et al.: Anatomy transfer. Acm Trans. Gr. 32(6), 188 (2013)
Avril, Q., Ribet, S., Ghafourzadeh, D. et al.:Animation setup transfer for 3D characters. Comput. Gr. Forum 115–126, (2016)
Müller, M., Heidelberger, B., Hennix, M., et al.: Position based dynamics. J. Vis. Commun. Image Representation 18(2), 109–118 (2007)
Bender, J., Müller, M., Otaduy, M.A., et al.: A survey on position-based simulation methods in computer graphics. Comput. Gr. Forum 33(6), 228–251 (2014)
Pan, J., Bai, J., Zhao, X., et al.: Real-time haptic manipulation and cutting of hybrid soft tissue models by extended position-based dynamics. Comput. Anim. Virtual Worlds 26(3–4), 321–335 (2015)
Macklin, M., Ller, M., Chentanez, N., et al.: Unified particle physics for real-time applications. Acm Trans. Gr. 33(4), 1–12 (2014)
Rumman, N.A., Fratarcangeli, M.: Position-based skinning for soft articulated characters. Comput. Gr. forum 34(6), 240–250 (2015)
PhysX-Nvidia. http://physxinfo.com/wiki/
Lipman, Y., Rustamov, R.M., Funkhouser, T.A.: Biharmonic distance. Acm Trans. Gr. 29(3), 483–496 (2010)
Yen, L., Fouss, F., Decaestecker, C., et al.: Graph nodes clustering based on the commute-time kernel, in proceedings of the 11th Pacific-Asia conference on knowledge discovery and data mining (PAKDD 2007). Lect. notes in Comput. Sci. 4426, 1037–1045 (2007)
Shepard, D.: A two-dimensional interpolation function for irregularly-spaced data. ACM Natl. Conf. 23, 517–524 (1968)
Acknowledgements
This research is supported by National Natural Science Foundation of China (No. 61402025, 61672149, 61532002).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Pan, J., Chen, L., Yang, Y. et al. Automatic skinning and weight retargeting of articulated characters using extended position-based dynamics. Vis Comput 34, 1285–1297 (2018). https://doi.org/10.1007/s00371-017-1413-6
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00371-017-1413-6