mitsuba-renderer / mitsuba3

Mitsuba 3: A Retargetable Forward and Inverse Renderer
https://www.mitsuba-renderer.org/
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AOV Integrator: Fix AD computation #1383

Closed rtabbara closed 1 week ago

rtabbara commented 1 week ago

By default, Dr.Jit’s AD system destructs the enqueued input graph during AD traversal. But the AOV integrator render_forward/render_backward functions consists of separate dr::forward_to/dr::backward_from calls for the AOV channels and inner integrator output. Hence we need to perform repeated propagation of gradients of a shared AD subgraph.