An immersive audio-visual experience in games and virtual reality requires fast calculation of diffraction-based acoustic effects. To maintain plausibility, the effects must retain spatial smoothness on source and listener motion within geometrically complex scenes. Precomputed wave-based techniques can render such results at low runtime CPU cost, but remain limited to static scenes. Modeling the occlusion effect of dynamic portals such as doors present an unresolved challenge to maintain audio-visual consistency. We present a fast solution implementable as a drop-in extension to existing precomputed systems. Key is a novel portal-search method that leverages precomputed propagation delay and direction data to find portals intervening the diffracted shortest path connecting dynamic source and listener at runtime. The method scales linearly with number of portals in worst case, far cheaper than explicit global path search that scales with scene area. We discuss culling techniques to accelerate further. The search algorithm is combined with geometric-acoustic approximations to model the additional direct and indirect energy loss from intervening portals depending on their dynamic closure state. We demonstrate plausible audio-visual animations within our system integrated with Unreal Engine 4 (TM) and Wwise (TM).

中文翻译：

---

用于预计算交互式声音传播的动态门户遮挡

游戏和虚拟现实中的沉浸式视听体验需要快速计算基于衍射的声学效果。为了保持合理性，效果必须在几何复杂的场景中保持源和听者运动的空间平滑度。预先计算的基于波形的技术可以以较低的运行时 CPU 成本呈现这样的结果，但仍然仅限于静态场景。模拟动态门户（例如门）的遮挡效果是保持视听一致性的一个未解决的挑战。我们提出了一种快速解决方案，可作为现有预计算系统的直接扩展实现。Key 是一种新颖的门户搜索方法，它利用预先计算的传播延迟和方向数据来查找干预运行时连接动态源和侦听器的衍射最短路径的门户。在最坏的情况下，该方法与门户的数量成线性关系，比随场景区域扩展的显式全局路径搜索便宜得多。我们讨论了进一步加速的剔除技术。搜索算法与几何声学近似相结合，根据其动态关闭状态对来自干预门户的额外直接和间接能量损失进行建模。我们在与 Unreal Engine 4 (TM) 和 Wwise (TM) 集成的系统中展示了合理的视听动画。