Gamified AR/VR Character Rendering and Animation-Enabling Technologies

  • Margarita Papaefthymiou
  • Steve Kateros
  • Stylianos Georgiou
  • Nikos Lydatakis
  • Paul Zikas
  • Vasileios Bachlitzanakis
  • George Papagiannakis
Chapter

Abstract

In recent years, the popularity of mixed reality (MR) environments has increased as they provide attractive and immersive experiences for educational, entertainment, and training purposes. The increasing advances of Augmented Reality (AR) and Virtual Reality (VR) hardware and software technologies also constitute an interesting area of research. In this work, we present the main pipeline followed for creating virtual character-based AR experiences, specifically in cultural heritage environments. Our main goal in this chapter is to compare different software methodologies for creating VR environments and present a complete novel methodology for authoring life-sized AR virtual characters and life-sized AR crowd simulation using only modern mobile devices. One important aspect of these environments that we focus on is creating realistic and interactive virtual characters via procedurally generated body and facial animations which are illuminated with real environment light. Virtual characters' transformations are handled efficiently using a single mathematical framework, the 3D Euclidean geometric algebra (GA), and the conformal geometric algebra (CGA) which is able to handle translations, rotations, and dilations. Using such a single algebraic framework, we avoid conversions between different mathematical representations; as a result, we achieve more efficient performance. We also compare the efficiency of different GA code generators—(a) the Gaigen library, (b) libvsr, and (c) Gaalop—so that a future user of GA can choose the most appropriate, currently available s/w library that will provide the most optimal and efficient results. Our main research involves the following questions: (a) Are novel, low-cost, modern HMDs suitable as VR platforms? (b) Which are the most appropriate s/w platforms needed to realize such VR digital heritage gamified experiences? (c) Can we achieve more efficient AR scene authoring? (d) Can we achieve more efficient AR animation interpolation and skinning using a single mathematical framework employing GA?

Keywords

Augmented reality Rendering Animation Geometric algebra Illumination Mobile precomputed radiance transfer Procedural character animation systems Conformal geometric algebra Virtual reality Animation blending Skinning GPU-based skinning Virtual character simulation AR crowd simulation Virtual characters Crowd simulation 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    G. Papagiannakis, P. Papanikolaou, E. Greasidou, P. Trahanias, glGA: an opengl geometric application framework for a modern, shader-based computer graphics curriculum. Eurographics 2014, 1–8 (2014)Google Scholar
  2. 2.
    M. Papaefthymiou, A. Feng, A. Shapiro, G. Papagiannakis, in A Fast and Robust Pipeline for Populating Mobile AR Scenes with Gamified Virtual Characters. SIGGRAPH Asia 2015 Mobile Graphics and Interactive Applications, SA ’15 (ACM, New York, NY, 2015), pp. 22:1–22:8Google Scholar
  3. 3.
    A. Shapiro, Building a Character Animation System (Springer, Berlin, 2011)CrossRefGoogle Scholar
  4. 4.
    B.H. Thomas, A survey of visual, mixed, and augmented reality gaming. Comput. Entertain. 10(1), 3:1–3:33 (2012)Google Scholar
  5. 5.
    A. Egges, G. Papagiannakis, N. Magnenat-Thalmann, Presence and interaction in mixed reality environments. Vis. Comput. 23(5), 317–333 (2007)CrossRefGoogle Scholar
  6. 6.
    M. Ponder, B. Herbelin, T. Molet, S. Scherteneib, B. Ulicny, G. Papagiannakis, N. Magnenat-Thalmann, D. Thalmann, in Interactive Scenario Immersion: Health Emergency Decision Training in Just Project. Proceedings from the 1st International Workshop on Virtual Reality Rehabilitation (VRMHR2002), pp. 87–101, 2002Google Scholar
  7. 7.
    A. Lewis Brooks, S. Brahnam, L.C. Jain, Technologies of inclusive well-being at the intersection of serious games, alternative realities, and play therapy, in Technologies of Inclusive Well-Being—Serious Games, Alternative Realities, and Play Therapy (2014), pp. 1–10Google Scholar
  8. 8.
    G. Papagiannakis, S. Schertenleib, M. Ponder, M. Arevalo, N. Magnenat-Thalmann, D. Thalmann, Real-Time Virtual Humans in AR Sites. 1st European Conference on Visual Media Production CVMP, pp. 273–276, 2004Google Scholar
  9. 9.
    L. Gun, M. Billinghurst, in A Component Based Framework for Mobile Outdoor AR Applications. SIGGRAPH Asia 2013 Symposium on Mobile Graphics and Interactive Applications (SA ‘13), pp. 173–179, 2013Google Scholar
  10. 10.
    Z.P. Huang, P. Hui, C. Peylo, D. Chatzopoulos, Mobile Augmented Reality Survey: A Bottom-Up Approach. Technical report, HKUST Technical report, 2013Google Scholar
  11. 11.
    G. Papagiannakis, E. Greasidou, P. Trahanias, M. Tsioumas, Mixed-reality geometric algebra animation methods for gamified intangible heritage. Int. J. Herit. Digit. 3, 683–699 (2015)CrossRefGoogle Scholar
  12. 12.
    T. Langlotz, S. Mooslechner, S. Zollmann, C. Degendorfer, G. Reitmayr, D. Schmalstieg, Sketching up the world: in situ authoring for mobile augmented reality. Pers. Ubiquit. Comput. 16(6), 623–630 (2012)CrossRefGoogle Scholar
  13. 13.
    A. Feng, Y. Huang, Y. Xu, A. Shapiro, Fast, automatic character animation pipelines. Comput. Anim. Virt. Worlds 25(1), 3–16 (2014)CrossRefGoogle Scholar
  14. 14.
    L. Dorst, D. Fontijne, S. Mann, Geometric Algebra for Computer Science (Morgan Kaufmann, San Francisco, CA, 2007)Google Scholar
  15. 15.
    G. Papagiannakis, in Geometric Algebra Rotors for Skinned Character Animation Blending. SIGGRAPH Asia 2013 Technical Briefs, SA ’13 (ACM, New York, NY, 2013), pp. 11:1–11:6Google Scholar
  16. 16.
    R. Wareham, J. Cameron, J. Lasenby, in Applications of Conformal Geometric Algebra in Computer Vision and Graphics, ed. by H. Li, P.J. Olver, G. Sommer. IWMM/GIAE, Lecture Notes in Computer Science, vol 3519 (Springer, Berlin, 2004), pp. 329–349Google Scholar
  17. 17.
    R. Wareham, J. Lasenby, in Mesh Vertex Pose and Position Interpolation Using Geometric Algebra. Articulated Motion and Deformable Objects, 5th International Conference, AMDO 2008, Port d’Andratx, Mallorca, Spain, 9–11 July 2008, Proceedings, pp. 122–131, 2008Google Scholar
  18. 18.
    L. Kavan, S. Collins, J. Žára, C. O’Sullivan, Geometric skinning with approximate dual quaternion blending. ACM Trans. Graph. 27(4), 105:1–105:23 (2008)CrossRefGoogle Scholar
  19. 19.
    N. Magnenat-Thalmann, F. Cordier, H. Seo, G. Papagianakis, in Modeling of Bodies and Clothes for Virtual Environments. Cyberworlds, 2004 International Conference on, pp. 201–208, November 2004Google Scholar
  20. 20.
    N. Magnenat-Thalmann, R. Laperrière, D. Thalmann, in Joint-Dependent Local Deformations for Hand Animation and Object Grasping. Proceedings on Graphics Interface ‘88 (Canadian Information Processing Society, Toronto, ON, 1988), pp. 26–33Google Scholar
  21. 21.
    S. Kateros, S. Georgiou, M. Papaefthymiou, G. Papagiannakis, M. Tsioumas, A comparison of gamified, immersive VR curation methods for enhanced presence and human–computer interaction in digital humanities. Int. J. Herit. Digit. Era 4(2), 2015 (2016) (also presented in “The 1st International Workshop on ICT for the Preservation and Transmission of Intangible Cultural Heritage”, EUROMED2014)Google Scholar
  22. 22.
    S. Kuntz, Sébastien Cb Kuntz, Creating VR Games—The Fundamentals (2014), pp. 1–10. http://cb.nowan.net/blog/2014/01/27/creating-vr-games-the-fundamentals/#more-1642
  23. 23.
    I. Oikonomidis, N. Kyriazis, A. Argyros, in Tracking the Articulated Motion of Two Strongly Interacting Hands (2012)Google Scholar
  24. 24.
    M. Pateraki, H. Baltzakis, P. Trahanias, Visual estimation of pointed targets for robot guidance via fusion of face pose and hand orientation. Comput. Vis. Image Underst. 120, 1–13 (2014)CrossRefGoogle Scholar
  25. 25.
    S. Kuntz, Gamasutra: Sebastien Kuntz’s Blog—Lessons from the VR Field (2014), pp. 1–9. http://www.gamasutra.com/blogs/SebastienKuntz/20140112/208452/Lessons_from_the_VR_field.php
  26. 26.
    Oculus VR Best Practices Guide, Oculus VR Best Practices Guide (2014), pp. 1–53. http://static.oculusvr.com/sdk-downloads/documents/OculusBestPractices.pdf
  27. 27.
    Giving Oculus Rift demos: Best practice|RenderingPipeline, Giving Oculus Rift Demos: Best Practice|RenderingPipeline (2014), pp. 1–6. http://renderingpipeline.com/2014/09/giving-oculus-rift-demos-best-practice/
  28. 28.
    D. Hestens, G. Sobczyk, Clifford Algebra to Geometric Calculus: A Unified Language for Mathematics and Physics (Fundamental Theories of Physics) (Springer, Dordrecht, 1984)CrossRefGoogle Scholar
  29. 29.
    K. Kanatani, Understanding Geometric Algebra: Hamilton, Grassmann, and Clifford for Computer Vision and Graphics (A K Peters/CRC Press, Boca Raton, FL, 2015)CrossRefMATHGoogle Scholar
  30. 30.
    P. Zikas, M. Papaefthymiou, V. Mpaxlitzanakis, G. Papagiannakis, in Life-Sized Group and Crowd Simulation in Mobile AR. Proceedings of the 29th International Conference on Computer Animation and Social Agents (CASA ‘16) (ACM, New York, NY, 2016), pp. 79–82Google Scholar
  31. 31.
    J. van den Berg, S. Patil, J. Sewall, D. Manocha, M. Lin, in Interactive Navigation of Multiple Agents in Crowded Environments. Proceedings of the 2008 Symposium on Interactive 3D Graphics and Games, I3D ’08 (ACM, New York, NY, 2008), pp. 139–147Google Scholar
  32. 32.
    J. van den Berg, M.C. Lin, D. Manocha, in Reciprocal Velocity Obstacles for Real-Time Multi-Agent Navigation. IEEE International Conference on Robotics and Automation (IEEE, 2008), pp. 1928–1935Google Scholar
  33. 33.
    M. Papaefthymiou, D. Hildenbrand, G. Papagiannakis, A conformal geometric algebra code generator comparison for virtual character simulation in mixed reality. Adv. Appl. Clifford Algebr., 1–16 (2016) (also presented in GACSE workshop, CGI 2016, Heraklion, Greece, June 2016)Google Scholar
  34. 34.
    M. Papaefthymiou, D. Hildenbrand, G. Papagiannakis, An inclusive conformal geometric algebra GPU animation interpolation and deformation algorithm. Vis. Comput., 1–9 (2016) (also presented in CGI 2016, Heraklion, Greece)Google Scholar

Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Margarita Papaefthymiou
    • 1
    • 2
  • Steve Kateros
    • 1
    • 2
  • Stylianos Georgiou
    • 1
    • 2
  • Nikos Lydatakis
    • 1
    • 2
  • Paul Zikas
    • 1
    • 2
  • Vasileios Bachlitzanakis
    • 1
    • 2
  • George Papagiannakis
    • 1
    • 2
  1. 1.Institute of Computer Science, Foundation for Research and Technology—HellasHeraklionGreece
  2. 2.Department of Computer ScienceUniversity of CreteHeraklionGreece

Personalised recommendations