论文标题
使用伴随方法计算光传输梯度
Computing Light Transport Gradients using the Adjoint Method
论文作者
论文摘要
本文提出了一个从连续伴随理论的新方程式，以计算传输理论控制的数量梯度。与在代码级别上工作的离散梯度ALA Autograd不同，我们首先制定连续理论，然后将其离散。本文的关键见解是，运输理论中的计算梯度类似于计算重要性，这是满足伴随方程的辐射量的数量。重要的是告诉我们在哪里寻找重要的光。这是本文的关键见解之一。实际上，这种数学旅程始于一个异想天开的思想，即这些伴随可能是相关的。因此，计算梯度比计算重要性字段更复杂。该洞察力和以下论文有望阐明这个复杂的问题，并简化现有路径示踪剂中梯度计算的实现。
This paper proposes a new equation from continuous adjoint theory to compute the gradient of quantities governed by the Transport Theory of light. Unlike discrete gradients ala autograd, which work at the code level, we first formulate the continuous theory and then discretize it. The key insight of this paper is that computing gradients in Transport Theory is akin to computing the importance, a quantity adjoint to radiance that satisfies an adjoint equation. Importance tells us where to look for light that matters. This is one of the key insights of this paper. In fact, this mathematical journey started from a whimsical thought that these adjoints might be related. Computing gradients is therefore no more complicated than computing the importance field. This insight and the following paper hopefully will shed some light on this complicated problem and ease the implementations of gradient computations in existing path tracers.
