Existing algorithms for rendering subsurface scattering in real time cannot deal well with scattering over longer distances. Kernels for image space algorithms become very large in these circumstances and separation does not work anymore, while geometry‐based algorithms cannot preserve details very well. We present a novel approach that deals with all these downsides. While for lower scattering distances, the advantages of geometry‐based methods are small, this is not the case anymore for high scattering distances (as we will show). Our proposed method takes advantage of the highly detailed results of image space algorithms and combines it with a geometry‐based method to add the essential scattering from sources not included in image space. Our algorithm does not require pre‐computation based on the scene's geometry, it can be applied to static and animated objects directly. Our method is able to provide results that come close to ray‐traced images which we will show in direct comparisons with images generated by PBRT. We will compare our results to state of the art techniques that are applicable in these scenarios and will show that we provide superior image quality while maintaining interactive rendering times.

中文翻译：

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高散射距离材料的交互式次表面散射

用于实时渲染次表面​​散射的现有算法无法很好地处理更长距离的散射。在这些情况下，图像空间算法的内核变得非常大，分离不再起作用，而基于几何的算法不能很好地保留细节。我们提出了一种处理所有这些缺点的新方法。虽然对于较低的散射距离，基于几何的方法的优势很小，但对于高散射距离（正如我们将展示的），情况不再如此。我们提出的方法利用图像空间算法的高度详细结果，并将其与基于几何的方法相结合，以添加来自未包含在图像空间中的源的基本散射。我们的算法不需要根据场景的几何形状进行预计算，它可以直接应用于静态和动画对象。我们的方法能够提供接近光线追踪图像的结果，我们将与 PBRT 生成的图像进行直接比较。我们将我们的结果与适用于这些场景的最先进技术进行比较，并表明我们提供了卓越的图像质量，同时保持了交互式渲染时间。