MPI Informatik
Synthesizing images of animated scenes with indirect illumination and glossy materials at interactive frame rates commonly ignores indirect shadows. In this work we extend a class of indirect lighting algorithms that splat shading to a framebuffer - we demonstrate deep screen space and ambient occlusion volumes - to include indirect visibility. To this end we propose the bounced z-buffer: While a common z-buffered framebuffer, at each pixel, maintains the distance from the closest surface and its radiance along a direction from the camera to that pixel, our representation contains the distance from the closest surface and its radiance after one indirect bounce into a certain other direction. Consequently, with bounced z-buffering, only the splat from the nearest emitter in one direction contributes to each pixel. Importance-sampling the bounced directions according to the product of cosine term and BRDF allows to approximate full shading by a simple sum of neighboring framebuffer pixels.
Oliver Nalbach, Tobias Ritschel, Hans-Peter Seidel
The Bounced z-Buffer for Indirect Visibility
Proc. VMV 2015
@inproceedings{Nalbach2015,
author = {Oliver Nalbach and Tobias Ritschel and Hans-Peter Seidel},
title = {The Bounced Z-Buffer for Indirect Visibility},
booktitle = {VMV '15: International Workshop on Vision, Modeling and Visualization},
publisher = {Eurographics Association},
year = {2015}
}