Extending the photon mapping method for realistic rendering of hot gaseous fluids: Natural Phenomena and Special Effects

With the increased sophistication and use of heated gas, fire, and explosion simulations in computer graphics applications, there is a corresponding impetus to improve the visual realism in the rendering of such simulated phenomena. In visualizing these turbulent fluids, an appropriate incorporation of their incandescent properties into the rendering significantly enhances the realism of visual effects. In this paper, we effectively synthesize the light emission phenomena of hot gaseous fluids by extending the photon mapping global illumination method. In particular, we add two new photon maps to capture the thermal radiation effects. First, we define an emission photon map to store the photons emitted within hot gaseous fluids. Second, we utilize additional flash and flash reflection photon maps, which are effective in creating a visual effect of light that intensively and instantly propagates outside hot gaseous fluids, visually capturing shock waves. Our current technique, while based on the theory of blackbody radiation, is parameterized to enable an animator to generate a wide range of visual effects with fairly intuitive user control. We demonstrate the effectiveness of our new rendering technique and user-controlled generation of visual effects with several example pictures and animations. Copyright © 2005 John Wiley & Sons, Ltd.