Real-Time Global Illumination Using Shadow Radiance

在计算机图形学中，一个尚未解决的核心问题是如何以实时帧速率计算动态场景的全局照明解决方案。全局照明用于为场景添加逼真的照明，不仅考虑直接来自光源的光，还考虑通过其他曲面反射间接产生的光。在这个建议中，我们考虑新的技术，旨在实时计算全局照明。许多应用程序，如培训，虚拟现实或娱乐，需要与虚拟场景交互的能力。例如，用户可能希望在建筑应用环境中移动家具。这需要根据场景中的变化实时更新所得到的照明。然而，当前的实时照明计算技术要么局限于静态场景，要么局限于非常简单的照明模型，例如具有硬阴影且没有间接照明的点光源，这降低了所得到的图像质量和真实感。这是不期望的，并且用于一般全局照明的实时方法仍然是突出的。当前全局照明技术不能处理动态场景的核心原因是需要在场景元素之间进行昂贵的可见性查询。在这个项目中，我们将开发一种新的方法来实时计算全局照明解决方案，而不需要昂贵的可见性查询。事实上，可见性将通过使用阴影辐射由算法隐式地处理。我们将使用游戏和设计应用程序设置来演示我们的技术的效率。在这两种情况下，照明将总是根据用户交互（例如，移动家具），这在以前是不可能的。

A core unsolved problem in computer graphics is how to compute a global illumination solution for dynamic scenes at real-time frame rates. Global illumination is used to add realistic lighting to scenes by taking into account not only light that comes directly from the light source but also indirectly through reflection by other surfaces. In this proposal, we consider new techniques that aim at computing global illumination in real-time. Many applications, such as training, virtual reality, or entertainment, require the ability to interact with a virtual scene. For instance, a user may wish to move furniture around in an architectural application setting. This necessitates updating the resulting illumination in real-time according to the changes in the scene. However, current techniques for real-time illumination computation are either limited to static scenes or to very simple lighting models, such as point lights with hard shadows and no indirect illumination, which decrease the resulting image quality and realism. This is undesirable and a real-time method for general global illumination is still outstanding. The core reason why present global illumination techniques cannot handle dynamic scenes is the need for costly visibility queries between scene elements. In this project, we will develop a new approach to computing global illumination solutions in real-time, without the need for costly visibility queries. In fact, visibility will be handled implicitly by the algorithm through the use of shadow radiance. We will demonstrate the efficiency of our technique using a game and a design application setting. In both scenarios the illumination will always be updated in real-time according to user interactions (e.g., moving furniture around), which has not been previously possible.