Deferred Neighboring Radiance Transfer

A research project by Salvatore Giuffrida
Conducted at Utrecht University at the Master Game and Media Technology program
Under supervision of Marries Hoef
Sep 2016

Deferred Neighboring Radiance Transfer is an approximated Global Illumination technique developed for use in videogame applications. Global Illumination models simulate how light propagates within a scene taking into account both direct and indirect light. The inclusion of indirect light enriches the scene, giving it a photo-realistic look. Global Illumination methods are too slow for use in real-time applications. Approximated techniques like DNRT are, therefore, necessary. DNRT modifies pre-existing light solutions for static environments enhancing them with reflections and occlusions from dynamic objects. This is done combining two core ideas: light redistribution and precomputation. The result is an efficient screen-space technique that can be used on any scene with only a minor impact on performance.

Global Illumination, Post Processing, Radiance Redistribution, Deferred Rendering


The demo allows to compare the proposed technique, DNRT, with rivaling methods, namely SSAO and HBAO. A corridor environment illuminated only by indirect light is populated with three dynamic objects. Each object can be selected (Left Click) and moved around the scene (Arrow Keys). DNRT, SSAO and HBAO can be swapped using the simple UI menu. DNRT simulates both reflection and occlusions, and changes the overall lighting conditions of the scene. SSAO and HBAO, instead, limit their effect to close proximity shadows. N.B. A 64 bit machine with a DX11 enabled GPU is necessary to run the demo.