Interactive image-space refraction of nearby geometry

ABSTRACT

Interactive applications often strive for realism, but framerate constraints usually limit realistic effects to those that run efficiently in graphics hardware. One effect largely ignored in interactive applications is refraction. We build upon a simple, image-space approach to refraction [Wyman 2005] that easily runs on modern graphics cards. This image-space approach requires two passes on a GPU, and allows refraction of distant environments through two interfaces. Our work explores extensions allowing the refraction of nearby opaque objects, at the cost of one additional pass to render nearby geometry to texture and a more complex fragment shader for computing refracted color. Like all image-based algorithms, aliasing can occur in certain circumstances, especially when a few texels are magnified to cover a sizable portion of screen space. However, our plausible refractions should suffice for many applications.

REFERENCES

• 1: Ulf Assarsson , Tomas Akenine-Möller, A geometry-based soft shadow volume algorithm using graphics hardware, ACM Transactions on Graphics (TOG), v.22 n.3, July 2003
• 2: Eric Chan , Frédo Durand, Rendering fake soft shadows with smoothies, Proceedings of the 14th Eurographics workshop on Rendering, June 25-27, 2003, Leuven, Belgium
• 3: Paul J. Diefenbach , Norman I. Badler, Multi-pass pipeline rendering: realism for dynamic environments, Proceedings of the 1997 symposium on Interactive 3D graphics, p.59-ff., April 27-30, 1997, Providence, Rhode Island, United States [doi>10.1145/253284.253308]
• 4: Donnelly, W. 2005. GPU Gems 2. Addison-Wesley, March, ch. Per-Pixel Displacement Mapping with Distance Functions, 123--136.
• 5: Stephane Guy , Cyril Soler, Graphics gems revisited: fast and physically-based rendering of gemstones, ACM Transactions on Graphics (TOG), v.23 n.3, August 2004
• 6: Ziyad S. Hakura , John M. Snyder, Realistic Reflections and Refractions on Graphics Hardware with Hybrid Rendering and Layered Environment Maps, Proceedings of the 12th Eurographics Workshop on Rendering Techniques, p.289-300, June 25-27, 2001
• 7: Heidrich, W., Lensch, H., Cohen, M. F., and Seidel, H.-P. 1999. Light field techniques for reflections and refractions. In Proceedings of the Eurographics Rendering Workshop, 187--196.
• 8: Kautz, J., Lehtinen, J., and Aila, T. 2004. Hemispherical rasterization for self-shadowing of dynamic objects. In Proceedings of the Eurographics Symposium on Rendering, 179--184.
• 9: Douglas Scott Kay , Donald Greenberg, Transparency for computer synthesized images, Proceedings of the 6th annual conference on Computer graphics and interactive techniques, p.158-164, August 08-10, 1979, Chicago, Illinois, United States
• 10: Erik Lindholm , Mark J. Kligard , Henry Moreton, A user-programmable vertex engine, Proceedings of the 28th annual conference on Computer graphics and interactive techniques, p.149-158, August 2001 [doi>10.1145/383259.383274]
• 11: Ren Ng , Ravi Ramamoorthi , Pat Hanrahan, Triple product wavelet integrals for all-frequency relighting, ACM Transactions on Graphics (TOG), v.23 n.3, August 2004
• 12: Eyal Ofek , Ari Rappoport, Interactive reflections on curved objects, Proceedings of the 25th annual conference on Computer graphics and interactive techniques, p.333-342, July 1998 [doi>10.1145/280814.280929]
• 13: Ohbuchi, E. 2003. A real-time refraction renderer for volume objects using a polygon-rendering scheme. In Proceedings of Computer Graphics International, 190--195.
• 14: Oliveira, G., 2000. Refractive texture mapping, part two. Gamasutra, November. http://www.gamasutra/features/20001117/oliveira_01.htm.
• 15: Timothy J. Purcell , Craig Donner , Mike Cammarano , Henrik Wann Jensen , Pat Hanrahan, Photon mapping on programmable graphics hardware, Proceedings of the ACM SIGGRAPH/EUROGRAPHICS conference on Graphics hardware, July 26-27, 2003, San Diego, California
• 16: Schmidt, C. M. 2003. Simulating Refraction Using Geometric Transforms. Master's thesis, Computer Science Department, University of Utah.
• 17: Peter-Pike Sloan , Jan Kautz , John Snyder, Precomputed radiance transfer for real-time rendering in dynamic, low-frequency lighting environments, ACM Transactions on Graphics (TOG), v.21 n.3, July 2002
• 18: Sousa, T. 2005. GPU Gems 2. Addison-Wesley, March, ch. Generic Refraction Simulation, 295--305.
• 19: Pauline Y. Ts'o , Brian A. Barsky, Modeling and rendering waves: wave-tracing using beta-splines and reflective and refractive texture mapping., ACM Transactions on Graphics (TOG), v.6 n.3, p.191-214, July 1987 [doi>10.1145/35068.35070]
• 20: Ingo Wald , Thomas Kollig , Carsten Benthin , Alexander Keller , Philipp Slusallek, Interactive global illumination using fast ray tracing, Proceedings of the 13th Eurographics workshop on Rendering, June 26-28, 2002, Pisa, Italy
• 21: Wand, M., and Strasser, W. 2003. Real-time caustics. Computer Graphics Forum 22, 3, 611--620.
• 22: Chris Wyman , Charles Hansen, Penumbra maps: approximate soft shadows in real-time, Proceedings of the 14th Eurographics workshop on Rendering, June 25-27, 2003, Leuven, Belgium
• 23: Chris Wyman, An approximate image-space approach for interactive refraction, ACM Transactions on Graphics (TOG), v.24 n.3, July 2005

INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS
      I.3.7 Three-Dimensional Graphics and Realism

Keywords:
hardware, interactive rendering, refraction