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arXiv · 2309.12496

Optical Photon Simulation with Mitsuba3

Adam C. S. Davis·Sacha Barré·Yangyang Cui·Keith L Evans·Marco Gersabeck·Antonin Rat·Zahra Montazeri
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Abstract

Optical photon propagation is an embarrassingly parallel operation, well suited to acceleration on GPU devices. Rendering of images employs similar techniques -- for this reason, a pipeline to offload optical photon propagation from Geant4 to the industry-standard open-source renderer Mitsuba3 has been devised. With the creation of a dedicated plugin for single point multi-source emission, we find a photon propagation rate of $2\times10^{5}$ photons per second per CPU thread using LLVM and $1.2\times10^{6}$ photons per second per GPU using CUDA. This represents a speed-up of 70 on CPU and 400 on GPU over Geant4 and is competitive with other similar applications. The potential for further applications is discussed.

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Adam C. S. Davis, Sacha Barré, Yangyang Cui, Keith L Evans, Marco Gersabeck, Antonin Rat, Zahra Montazeri. 2023-09-21. Optical Photon Simulation with Mitsuba3. https://arxiv.org/abs/2309.12496

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