Applying Visual Analytics to Phyiscally-Based Rendering

G. Simons, S. Herholz, V. Petitjean, T. Rapp, M. Ament, H. Lensch, C. Dachsbacher M. Eisemann, E. Eisemann

Computer Graphics Forum

Overview of our visualization tool that combines information visualization and visual analytics techniques with phyiscally-based rendering. In detail, the parallel coordinates plot is shown in yellow, render views in red and blue, and the scene view in green.


Physically-based rendering is a well understood technique to produce realistic-looking images. However, different algorithms exist for efficiency reasons, which work well in certain cases but fail or produce rendering artifacts in others. Few tools allow a user to gain insight into the algorithmic processes. In this work, we present such a tool, which combines techniques from information visualization and visual analytics with physically-based rendering. It consists of an interactive parallel coordinates plot, with a built-in sampling-based data reduction technique to visualize the attributes associated with each light sample. 2D and 3D heat maps depict any desired property of the rendering process. An interactively rendered 3D view of the scene displays animated light paths based on the user’s selection to gain further insight into the rendering process. The provided interactivity enables the user to guide the rendering process for more efficiency. To show its usefulness we present several applications based on our tool. This includes differential light transport visualization to optimize light setup in a scene, finding the causes of and resolving rendering artifacts, such as fireflies, as well as a path length contribution histogram to evaluate the efficiency of different Monte Carlo estimators.