Stefan Seipel
Department of Information Technology, Uppsala University, Sweden \ and Department of Mathematics and Computer, Science, University of Gävle, Sweden
Anders Nivfors
Department of Information Technology, Uppsala University, Sweden
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Ingår i: SIGRAD 2006. The Annual SIGRAD Conference; Special Theme: Computer Games
Linköping Electronic Conference Proceedings 19:1, s. 1–6
Publicerad: 2006-11-22
ISBN:
ISSN: 1650-3686 (tryckt), 1650-3740 (online)
In this paper we present a multi-pass rendering approach for approximating the effects of multiple refractions and specular reflections in transparent or semitransparent materials. These optical effects are typically found in natural materials like ice but also in glass artworks. The rendering technique proposed in this paper is intended to perform at real-time frame rates and aim at achieving naturally looking effects rather than simulating physically correct interaction between light and matter. Part of our method is an improved image space technique for clipping a geometry using the Boolean difference of two geometries in order to create internal surfaces of reflection inside transparent objects. It employs a number of generic cracks surface geometries which are clipped against the geometry to be rendered. Reflection and refraction effects on the ice are implemented by using environment mapping. Two-sided refraction is accomplished by combining the normal vectors of the front and back side of the ice object. Our method renders icy objects with convincing visual appearance in real-time on state-of-the-art graphics hardware.
Computer Graphics; Modelling of Natural Phenomena; Illumination Models; Realtime Rendering Algorithms
BLINN; J. F.; and NEWELL; M. E. 1976. Texture and Reflection in Computer Generated Images. Communications of the ACM v. 19 i. 10; ACM Press; New York; 542-547.
CARLSON; M.; MUCHA; P. J.; VAN HORN III; R. B.; and TURK; G. 2002. Melting and Flowing. In Proceedings of the 2002 ACM SIGGRAPH/Eurographics symposium on Computer animation; ACM Press; New York; 167-174.
GÉNEVAUX; O.; LARUE; F.; and DISCHLER; J. 2006. Interactive Refraction on Complex Static Geometry using Spherical Harmonics. In Proceedings of the 2006 symposium on Interactive 3D graphics and games; ACM Press; New York; 145-152.
GOLDFEATHER; J. 1986. Fast Constructive Solid Geometry Display in the Pixel-Powers Graphics System. In Proceedings of the 13th annual conference on Computer graphics and interactive techniques; ACM Press; New York; 107-116.
JENSEN; L. S.; and GOLIAS; R. 2001. Deep-Water Animation and Rendering. Gamasutra article. http://www.gamasutra.com; April 2006.
JONES; M. W. 2003. Melting Objects. In Journal of WSCG 2003; 247–254.
JULIANO; J.; and SANDMEL; J. (contact persons). 2006. Framebuffer object extension specification. http://oss.sgi.com/projects/oglsample/ registry/EXT/framebuffer_object.txt; May 2006.
KHAN; A. 2004. Dual-sided Refraction Simulation. Shadertech Contest; Summer 2004. http://www.shadertech.com/contest; April 2006.
KHARITONSKY; D.; and GONCZAROWSKI; J. 1993. Physically based model for icicle growth. The Visual Computer: International Journal of Computer Graphics; Springer-Verlag New York Inc.; Secaucus; 88-100.
KIM; T.; and LIN; M. C. 2003. Visual Simulation of Ice Crystal Growth. In Proceedings of the 2003 ACM SIGGRAPH/Eurographics symposium on Computer animation; Eurographics Association; Aire-la-Ville; 86-97.
KIM; T.; HENSON; M.; and LIN; M. C. 2004. A hybrid Algorithm for Modeling Ice Formation. In Proceedings of the 2004 ACM SIGGRAPH/Eurographics symposium on Computer animation; ACM Press; New York; 305-314.
MCREYNOLDS; T.; and BLYTHE; D. 1996. Programming with OpenGL: Advanced Rendering. Course notes from ACM SIGGRAPH 1996 Course 23; ACM Press; New York; 31- 42.
NIVFORS; A. 2006. Real-time rendering of ice. Masters Project Thesis in Computer Science. Department of information Technology; Uppsala University.
NORDLING; C.; and ÖSTERMAN; J. 1999. Physics handbook for Science and Engineering. Studentlitteratur.
WITTEN; T. A.; and SANDER; L. M. 1981. Diffusion-limited aggregation; a kinetic critical phenomenon. Physical Review Letters 47; 1400–1403.
WYMAN; C. 2005. An Approximate Image-Space Approach for Interactive Refraction. In Proceedings of ACM SIGGRAPH 2005; ACM Press; New York; 1050-1053.
