Visual Comput (2007) 23: 679–687 DOI 10.1007/s00371-007-0162-3 ORIGINAL ARTICLE Kyungha Min Dimitris Metaxas A combustion-based technique for fire animation and visualization Published online: 28 June 2007  Springer-Verlag 2007 K. Min (✉) Dept. of Digital Media, Sangmyung Univ., Korea minkh@smu.ac.kr D. Metaxas CBIM, Rutgers Univ., USA dnm@cs.rutgers.edu Abstract In this paper, we present a new fire animation and visualization scheme. The most difficult problem in creating fire animation is how to simulate the mechanism of emitting the light and heat of fire. We attack the difficulty by presenting a simu- lation scheme for the combustion process in voxelized space where the numerical solution of the classical fluid equations is implemented. Therefore, the combustion process is simulated at each voxel and the amount of heat generated at the voxel is estimated. The generated heat will increase the temperature at the voxel, which results in the increase of the turbulent motion of fire. We also propose a visualization scheme that is based on a photon mapping algorithm in order to render fire and various lighting effects of fire to the environments. Keywords Fluid simulation · Fire · Natural phenomena · Photon mapping 1 Introduction As digital entertainment industries require enhanced real- ism in computer-generated animations, the technologies for creating animations of natural phenomena such as water, flood, smoke, and fire have become one of the most chal- lenging problems in 3D computer graphics. Among the nat- ural phenomena animated in computer graphics, fire and flames are recognized as the most difficult to animate. The inherent difference between fire and other fluids such as water and smoke is that fire is a kind of fluid that emits light and heat. Therefore, simulating the emission of light and heat is the most important factor in develop- ing a framework that creates realistic animation of fire and flames. Many researchers in physics and fire-related fields reveal that the combustion process is the source mechan- ism of the emission. In this paper, we extend the prelim- inary combustion model in [16] and present a framework that simulates the combustion of fuels in the voxelized space where the numerical solution of the classical fluid equations is implemented. At each voxel, the combustion of the fuels inside the voxel is simulated and the amount of heat that is generated as the result of the combustion is estimated. The generated heat increases the temperature of the voxel, and the combusted portion of fuels turns to soot. The increased temperature affects the numerical solution of the fluid equations, which will increase the turbulent motions of fire. By combining the simulation of combus- tion and the numerical solution of the fluid equations, we present a framework that supports the realistic animation of fire and flames. Another difficulty in fire animation is how to visualize fire and its lighting effects on the environment. According to the blackbody radiation, the color of fire is dependent on the temperature. Several researches surveyed the black- body radiation and implemented the spectrum of the tem- perature and the color of hot fluids [12, 17]. In computer graphics, however, fires may have different visualizations according to the animator’s decision. Therefore, controlla- bility over the visualizations of fire is strongly required. In this paper, we exploit the user-editable temperature-color graph in [16] and the photon mapping method in [11] to