A New Method for Modeling Clouds Combining Procedural and Implicit Models
Anselmo Antunes Montenegro, Icaro Baptista, Bruno José Dembogurski, Esteban Clua · 2017
Cloud models are important components in 3D open environment games and virtual reality applications. In the literature, different approaches have been proposed to solve the problem of modeling the complex geometry and texture of clouds including physical simulation, photo-based modeling and a combination of implicit modeling with procedural techniques. The latter is simple and produces satisfactory results and can be also done in realtime. Nevertheless, it is still difficult to produce the desired results by combining implicit modeling with procedural techniques. The reasons for this limitation are twofold. First, the parameters are not intuitive and intricately coupled with each other. The second reason is that it is hard to combine the overall shape defined by the implicit model with the details generated by the procedural models in a smooth and localized way. In this work, we propose a new way of modeling clouds by combining volumetric implicit modeling with procedural noise techniques. Differently from previous works, the details produced by noise are attached to each implicit primitive independently, in different scales, before they are smoothly blended. This provides a greater level of control in the process of designing and modeling the clouds. By implementing our technique in GPUs it is possible to change the parameters and the blending of primitives in realtime and observe immediately the produced results. This interactive behavior enables the modeler to more easily build and experiment different versions of his ideas. Although we applied this technique to cloud modeling we show that the same approach can be useful for modeling many natural objects as rocks, terrain and planet shapes, among others.