遊色効果再現のための三次元ボロノイ分割を用いたオパールのモデリング

Most opals used as gemstones have an optical effect–’play of color’, to produce rainbow-colored patterns. While most of gemstones, such as diamond, ruby, and sapphire, are classified as monocrystal or polycrystal materials, opal is classified as amorphous materials with a complex internal structure. Therefore, visual simulation modeling of opal requires a necessary and sufficient spatial scale under the constraints of computational resources. In this study, we propose a new method for modeling the internal structure of opal using three-dimensional Voronoi tessellation, which enables us to simulate play of color based on crystallography. By focusing on the characteristics of the three-dimensional Voronoi diagram, we reduce space complexity significantly compared to existing studies. Furthermore, we show that it is possible to model a variety of opal using four parameters: the diameter of particles that make up opal, scattering coefficient and absorption coefficient due to impurities contained within the particles, and the tilt of diffraction grating.