TY - JOUR KW - caustics KW - daylight simulation KW - light redirection KW - Monte Carlo KW - physically based rendering KW - raytracing AU - Roland Schregle AU - Lars Grobe AU - Stephen Wittkopf AB - Abstract Daylight redirecting components (DRCs) are characterised by complex transmissive and reflective behaviour that is difficult to predict accurately largely due to their highly directional scattering, and the caustics this produces. This paper examines the application of progressive photon mapping as a state of the art forward raytracing technique to efficiently simulate the behaviour of such DRCs, and how this approach can support architects in assessing their performance. Progressive photon mapping is an iterative variant of static photon mapping that effects noise reduction through accumulation of results, as well as a reduction in bias inherent to all density estimation methods by reducing the associated bandwidth at a predetermined rate. This not only results in simplified parametrisation for the user, but also provides a preview of the progressively refined simulation, thus making the tool accessible to non-experts as well. We demonstrate the effectiveness of this technique with an implementation based on the Radiance photon mapping extension and a case study involving retroreflecting prismatic blinds as a representative DRC. BT - Solar Energy DO - 10.1016/j.solener.2015.01.041 LA - eng N2 - Abstract Daylight redirecting components (DRCs) are characterised by complex transmissive and reflective behaviour that is difficult to predict accurately largely due to their highly directional scattering, and the caustics this produces. This paper examines the application of progressive photon mapping as a state of the art forward raytracing technique to efficiently simulate the behaviour of such DRCs, and how this approach can support architects in assessing their performance. Progressive photon mapping is an iterative variant of static photon mapping that effects noise reduction through accumulation of results, as well as a reduction in bias inherent to all density estimation methods by reducing the associated bandwidth at a predetermined rate. This not only results in simplified parametrisation for the user, but also provides a preview of the progressively refined simulation, thus making the tool accessible to non-experts as well. We demonstrate the effectiveness of this technique with an implementation based on the Radiance photon mapping extension and a case study involving retroreflecting prismatic blinds as a representative DRC. PY - 2015 SP - 327 EP - 336 T2 - Solar Energy TI - Progressive photon mapping for daylight redirecting components UR - http://www.sciencedirect.com/science/article/pii/S0038092X15000559 VL - 114 SN - 0038-092X ER -