OpenGL Insights

Depth of Field with

Bokeh Rendering

Charles de Rousiers and Matt Pettineo

15.1 Introduction

In order to increase realism and immersion, current games make frequent use of

depth of field to simulate lenticular phenomena. Typical implementations use screen-

space filtering techniques to roughly approximate a camera’s circle of confusion for

out-of-focus portions of a scene. While such approaches can provide pleasing results

with minimal performance impact, crucial features present in real-life photography

are still missing. In par ticular, lens-based cameras produce a phenomenon known

as bokeh (blur in Japanese). Bokeh manifests as distinctive geometric