Ray tracing on the GPU has been synergistically operating alongside rasterisation in interactive rendering engines for some time now, in order to accurately capture certain illumination effects. In the same spirit, in this paper, we propose an implementation of progressive photon mapping entirely on the rasterisation pipeline, which is agnostic to the specific GPU architecture, in order to synthesise images at interactive rates. While any GPU ray tracing architecture can be used for photon mapping, performing ray traversal in image space minimises acceleration data structure construction time and supports arbitrarily complex and fully dynamic geometry. Furthermore, this strategy maximises data structure reuse by encompassing rasterisation, ray tracing and photon gathering tasks in a single data structure. Both eye and light paths of arbitrary depth are traced on multi-view deep G-buffers, and photon flux is gathered by a properly adapted multi-view photon splatting. In contrast to previous methods exploiting rasterisation to some extent, due to our novel indirect photon splatting approach, any event combination present in photon mapping is captured. We evaluate our method using typical test scenes and scenarios for photon mapping methods and show how our approach outperforms typical GPU-based progressive photon mapping.

中文翻译：

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基于光栅化的渐进光子映射

一段时间以来，GPU 上的光线追踪一直与交互式渲染引擎中的光栅化协同工作，以准确捕捉某些照明效果。本着同样的精神，在本文中，我们提出了一种完全在光栅化管道上实现渐进式光子映射的方法，它与特定的 GPU 架构无关，以便以交互速率合成图像。虽然任何 GPU 光线追踪架构都可以用于光子映射，但在图像空间中执行光线遍历可以最大限度地减少加速数据结构的构建时间，并支持任意复杂的全动态几何。此外，该策略通过在单个数据结构中包含光栅化、光线追踪和光子收集任务，最大限度地重用数据结构。任意深度的眼睛和光路都在多视图深 G 缓冲区上跟踪，光子通量通过适当调整的多视图光子溅射收集。与以前在某种程度上利用光栅化的方法相比，由于我们新颖的间接光子溅射方法，可以捕获光子映射中存在的任何事件组合。我们使用光子映射方法的典型测试场景和场景来评估我们的方法，并展示我们的方法如何优于典型的基于 GPU 的渐进光子映射。