Development of a Method for Computer Animation of Water Droplet Flow

这个项目已经开发出一种方法来生成水滴的逼真动画，例如车辆的挡风玻璃。该方法的应用之一可以被认为是在挡风玻璃上的水滴的动画。这一过程对驱动模拟器至关重要。该方法采用离散环境中的粒子系统来计算水滴在表面上的运动，并通过环境映射来表示透明属性，从而通过透明物体快速渲染场景。完全由计算机生成的挡风玻璃上水滴的动画和视频组成证明了所提出方法的有效性。一种模拟水滴流动的方法：为了模拟水滴的流动，该方法考虑了作用于水滴的主导因素。如重力和界面张力等。将该方法扩展到三维空间，我们还开发了一种在三维空间中模拟水滴下落的方法。一种合成水滴和视频序列的方法：在为驾驶模拟器和电影生成场景时，有时需要改变从摄像机拍摄的图像序列的天气条件。该项目开发了一种从晴天拍摄的图像序列中生成雨天场景的方法。图像被分割成三种区域：天空、道路和所有其他周围区域，包括建筑物和树木。每个区域都以不同的方式进行处理，以产生下雨的场景。本文还提出了一种水滴与修改后的视频序列之间的图像合成方法。以车辆驾驶员座位上的一个场景为例，验证了所开发方法的有效性。

This project has developed a method for generating a realistic animation of water droplets, such as the windshield of a vehicle, for example. One of the method's applications can be considered the animation of water droplets on a windshield. a process vital for drive simulators. The proposed method employs a particle system in a discrete environment to calculate the movement of water droplets on a surface, and environment mapping for indicating the property of transparency to quickly render scenes through transparent objects. Fully computer generated animations and video compositions of water droplets on a windshield demonstrate the usefulness of the proposed method1. A method for simulating water droplet flow :To simulate the flow of water droplets, the developed method takes into account the dominant factors acting on the water droplets. such as gravity and interfacial tensions, etc. Extending the method to a three dimensional method, we also developed a method for simulating a water droplet fall in a 3D space.2. A method for compositing water droplets and a video sequence :In generating scenes for driving simulators and movies, it is at times desirable to alter the weather conditions of image sequences taken from a video camera. The project has developed a method for generating a rainy scene from an image sequence taken on a clear day. An image is segmented into three kinds of area : sky, road, and all the other surrounding area, including buildings and trees. Each area is processed in different ways to generate the rainy scene. An image composition method between water droplets and a modified video sequence is also developed. A scene taken from a vehicle driver's seat is applied to demonstrate the usefulness of the developed method.