Due to high computational expense of simulating the physical model of atmospheric effect, rendering realistic natural light phenomena in real time is a challenging work. In this paper, we present a new approach for dynamic light shaft construction and rendering. Unified volumes construction is proposed for both dynamic light shaft and shadow, which is embedded into an efficient method of rendering natural light shafts with atmospheric scattering. We present the analytic formula of scattering computation without numerical integration and its implementation on current GPU. Our approach can simulate not only the lighting effect with single light source but also multiple parallel light sources according to the physical model of skylight and sunlight. © 2008 Elsevier Ltd. All rights reserved.