lightweight-photon-mapping | Lightweight Photon Mapping sample implementation

lightweight-photon-mapping is a C++ library. lightweight-photon-mapping has no bugs, it has no vulnerabilities and it has low support. You can download it from GitHub.

Our extensions to the original Mitsuba source code consist of the following major components distributed across multiple files:. All code, except for the required extensions to the emitters, can be found in src/integrators/lpm/. The core contribution of the lightweight photon mapping paper, determining the usefulness of a photon, is implemented in the file usefulness.h. Histograms of the image contribution of (useful) photons are built and used for the importance sampling of emission in the files emission_sampler.h and emission_sampler.cpp. The integrator itself is defined in the files lpm.h and lpm.cpp. The files path_sampler.h and path_sampler.cpp provide functionality to trace paths from either the camera or the lights into the scene. They are used in cam_trace.h, cam_trace.cpp, light_trace.h, and light_trace.cpp to compute image contributions from all path sampling techniques. The files mis.h and mis.cpp provide code to combine the estimates via multiple importance sampling (MIS). The derivation of the MIS weights can be found in the VCM paper, the method used to compute the weights is inspired by the approach described in the tech report on implementing VCM. The remaining files define datastructures and utility functions required for the implementation, like the hash grid used for photon mapping and the 4D histograms used for emission guiding.