Efficient atmospheric rendering for mobile virtual globes

Abstract

Most virtual globe systems feature a rendering of the atmosphere that surrounds the earth. This element is so widespread that seeing a virtual earth without a surrounding halo makes the image seem much more artificial. Atmospheric rendering is a costly process aimed to enhance the realism and beauty of the scene. For that reason many virtual globe systems, specially in low-resourced devices, rely on simplified schemes to represent the atmosphere. However, the accurate representation of the atmosphere implies the volumetric rendering of the semi-transparent air mass that covers the whole geographical scene. Thus, the color of each pixel is composed of the light scattered by all the points in space projected on that pixel. The present work takes advantage of the spherical symmetry of the atmosphere’s mathematical model to implement efficiently this volumetric rendering on mobile devices.