Study on Display System of Natural Phenomena by Using Interactive Computer Graphics

本课题的研究课题是利用计算机图形学技术对自然现象进行逼真的渲染。我们专注于天空，云，烟，沙漠场景和大气效果，如光轴。这些现象有一个共同的特点，就是它们都是由小粒子的作用组成的。本研究包括以下内容：(1)自然现象光学特性建模；(2)自然现象动力学；(3)自然现象交互显示系统；(4)利用动画对系统性能进行评价。对于(1)，现实世界中的一些物质是由颗粒组成的，如沙子、空气分子和水蒸气。为了创建逼真的图像，需要基于物理的模拟和渲染。特别是，颜色在很大程度上取决于粒子的光散射特性。对于(2)，建模过程包括创建物体的形状，它们的动力学和它们的物理性质，如表面反射率。因此，已经开发了许多建模方法来解决这个问题。然而，使用这些方法，获得逼真的形状和运动是非常耗时的。用于模拟烟雾的流体动力学，云运动和沙丘的元胞自动机。对于(3)，最近图形硬件的处理速度越来越快。此外，即使在低端pc上也可以使用高性能图形硬件。这些事实鼓励我们开发硬件加速的方法来渲染逼真的图像。对于(4)，我们创作了自然现象的动画视频。因此，我们写了9篇与这个项目相关的论文。

The research topic of this project is to display realistic rendering of natural phenomena by using Computer Graphics technology. We focus on sky, clouds, smoke, desert scenes and atmospheric effects, such as shafts of light. These phenomena have the common feature that they are consist of the effects of small particles. This research includes the following elements (1) modeling of optical property of natural phenomena, (2) dynamics of natural phenomena, (3) interactive display system of natural phenomena, and (4) evaluation of system performance by using animation.For (1), some of material in real world consists of particles such as sands, air molecules, and water vapor. To create realistic images, physical based simulation and rendering are required. In particular, the color greatly depends on the properties of light scattering due to particles. For (2), the modeling process includes the creation of shapes of objects, their dynamics and their physical properties such as surface reflectance Therefore, a lot of modeling methods have been developed to address this problem. Using these methods, however, obtaining realistic-looking shapes and motion is very time consuming. For the simulation of fluid dynamics for smoke, cellular automata for cloud motion and sand dunes. For (3), the processing speed of graphics hardware has become faster and faster recently. In addition, high performance graphics hardware is available even on low-end PCs. These facts have encouraged us to develop hardware-accelerated methods for rendering realistic images. For (4), we have created the animation videos of natural phenomenaAs a result, we have written nine papers related to this project.