Advertisement

Real-Time Ray Tracing with Spherically Projected Object Data

  • Bridget Makena Winn
  • Reed Garmsen
  • Irene Humer
  • Christian EckhardtEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11844)

Abstract

As raytracing becomes feasible in regards to computational costs for real-time applications, new challenges emerge to achieve sufficient quality. To aim for an acceptable framerate, the amount of consecutive rays is strongly reduced to keep the workload on the GPU low, but sophisticated approaches for denoising are required. One of the major bottlenecks is finding the ray intersection with the geometry. In this work, we present a fast alternative by pre-computing a spherical projection of an object and reduce the cost of intersection-testing independent of the vertex count by projecting the object onto a circumscribed sphere. Further on, we test our Spherical Projection Approximation (SPA) by implementing it into a DirectX Raytracing (DXR) framework and comparing framerates and outcome quality for indirect light with DXR’s native triangle intersection for various dense objects. We found, that our approach not only hails comparable quality in representing the indirect light, but is also significantly faster and consequently provides a raytracing alternative to achieve real-time capabilities for complex scenes.

Keywords

Real-time raytracing DiretX Raytracing Intersection shaders 

References

  1. 1.
    Crassin, C., Neyret, F., Sainz, M., Green, S., Eisemann, E.: Interactive indirect illumination using voxel cone tracing. In: Computer Graphics Forum (Proceedings of Pacific Graphics 2011), vol. 30, 7 September 2011Google Scholar
  2. 2.
    Kaplanyan, A., Dachsbacher, C.: Cascaded light propagation volumes for real-time indirect illumination. In: Proceedings of the 2010 ACM SIGGRAPH symposium on Interactive 3D Graphics and Games (I3D 2010), pp. 99–107. ACM, New York, NY, USA.  https://doi.org/10.1145/1730804.1730821
  3. 3.
    Dachsbacher, C., Stamminger, M.: Reflective shadow maps. In: Proceedings of the 2005 Symposium on Interactive 3D Graphics and Games (I3D 2005), pp. 203–231. ACM, New York, NY, USA.  https://doi.org/10.1145/1053427.1053460
  4. 4.
    Appel, A.: Some techniques for shading machine renderings of solids. In: Proceedings of the April 30-May 2, 1968, Spring Joint Computer Conference (AFIPS 1968 (Spring)), pp. 37–45. ACM, New York, NY, USA.  https://doi.org/10.1145/1468075.1468082
  5. 5.
    Kajiya, F.T.: The rendering equation. In: Evans, D.C., Athay, R.J. (eds.) Proceedings of the 13th Annual Conference on Computer Graphics and Interactive Techniques (SIGGRAPH 1986), pp. 143–150. ACM, New York, NY, USA.  https://doi.org/10.1145/15922.15902
  6. 6.
    Nicodemus, F.E.: Directional reflectance and emissivity of an opaque surface. Appl. Opt. 4, 767–775 (1965)CrossRefGoogle Scholar
  7. 7.
  8. 8.
    SIGGRAPH 2018 NVIDIA talk. http://intro-to-dxr.cwyman.org/presentations/IntroDXR_RaytracingShaders.pdf. Accessed 15 July 2019
  9. 9.
  10. 10.
    Boksansky, J., Wimmer, M., Bittner, J.: Ray traced shadows: maintaining real-time frame rates. In: Haines, E., Akenine-Möller, T. (eds.) Ray Tracing Gems, pp. 159–182. Apress, Berkeley (2019).  https://doi.org/10.1007/978-1-4842-4427-2_13CrossRefGoogle Scholar
  11. 11.
    Wyman, C., Marrs, A.: Introduction to DirectX raytracing. In: Haines, E., Akenine-Möller, T. (eds.) Ray Tracing Gems. Apress, Berkeley (2019).  https://doi.org/10.1007/978-1-4842-4427-2_3CrossRefGoogle Scholar
  12. 12.
    Gribble, C.: Multi-hit ray tracing in DXR. In: Haines, E., Akenine-Möller, T. (eds.) Ray Tracing Gems. Apress, Berkeley, CA (2019).  https://doi.org/10.1007/978-1-4842-4427-2_9CrossRefGoogle Scholar
  13. 13.
    Akenine-Möller, T., Nilsson, J., Andersson, M., Barré-Brisebois, C., Toth, R., Karras, T.: Texture level of detail strategies for real-time ray tracing. In: Haines, E., Akenine-Möller, T. (eds.) Ray Tracing Gems. Apress, Berkeley, CA (2019).  https://doi.org/10.1007/978-1-4842-4427-2_20CrossRefGoogle Scholar
  14. 14.
    Szirmay-Kalos, L., Aszódi, B., Lazányi, I., Premecz, M.: Approximate ray-tracing on the GPU with distance impostors. Comput. Graph. Forum 24, 695–704 (2005).  https://doi.org/10.1111/j.1467-8659.2005.0m894.x. https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1467-8659.2005.0m894.xCrossRefGoogle Scholar
  15. 15.
    Barré-Brisebois, C., et al.: Hybrid rendering for real-time ray tracing. In: Haines, E., Akenine-Möller, T. (eds.) Ray Tracing Gems. Apress, Berkeley (2019).  https://doi.org/10.1007/978-1-4842-4427-2_25CrossRefGoogle Scholar
  16. 16.
    Liu, E., Llamas, I., Cañada, J., Kelly, P.: Cinematic rendering in UE4 with real-time ray tracing and denoising. In: Haines, E., Akenine-Möller, T. (eds.) Ray Tracing Gems. Apress, Berkeley (2019).  https://doi.org/10.1007/978-1-4842-4427-2_19CrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.California Polytechnic State UniversitySan Luis ObispoUSA

Personalised recommendations