Indigo Sun & Sky
Planet-scale atmospheric simulation
Landscape by yonosoy

Unrivaled realism

Unlike other rendering systems which rely on so-called practical models based on approximations, Indigo's sun and sky system is based on a planet-scale simulation, derived directly from physical principles.

Normally this would be prohibitively expensive to compute, however the simulation results have been accurately stored and compressed with full spectral information, allowing for fast rendering.

Physical accuracy

Based entirely on physical phenomena such as Rayleigh/Mie scattering and data sourced from NASA, Indigo's atmospheric simulation is highly accurate.

Multiple scattering of light authentically recreates the red and orange sky tones seen during sunrise and sunset.

Rayleigh scattering of light creates the blue sky tones familiar to everyone.

Mie scattering of light off water droplets creates the bright region around the sun and the band of white near the horizon.

Indigo's full spectral simulation preserves the subtle shifts in hues at different times of the day that are difficult to recreate in any other way.

Fast and easy to use

The simulation is captured in a form similar to an environment map, but with more spectral data, to accurately capture the full simulation at all wavelengths.

Capturing the simulation in this way allows it to render just as fast as the old sky model within Indigo, while greatly improving the realism over the old model.

You can change the sun direction in realtime, and see the resulting change in lighting immediately.