Table of Contents

This page gives an overview of the two global illumination render elements that may be created through V-Ray and how they are used in compositing.

 

Overview

Global Illumination is the indirect lighting bouncing around within a scene to contribute to the overall illumination, as opposed to direct lighting from a light source.

The Global Illumination Render Elements store indirect lighting information calculated in the scene. The following passes may be generated:

  • Global Illumination Render Element (GI) - Stores the diffuse surface global illumination in a scene when Global Illumination is enabled. This pass is already attenuated by the diffuse contribution in the scene and can be used directly in composite.

  • Raw Global Illumination Render Element (GI Raw) - Stores the raw information for the indirect lighting information calculated in the scene, untouched by the diffuse contribution. This pass is used to fine-tune the GI in a scene before attenuating it with the diffuse contributions of the scene.

 

The Global Illumination render element itself (GI) can be used in Back to Beauty compositing to add in the GI lighting contribution to the scene. The GI contribution may be adjusted (tinted, brightened, darkened, etc.) in the composite as needed without the need to rerender the scene.

When even more control over the GI contribution to the final image is desired, this main Global Illumination Render Element can be re-created by multiplying the Raw Global Illumination Render Element with the Diffuse Render Element:

GI Raw x Diffuse = GI

 

 

Render Element Examples


 


Global Illumination (GI) Render Element

 


Raw Global Illumination (GI Raw) Render Element

 

 

 

Notes

  • When Raw Global Illumination is needed in the composite, please make sure to also render the Global Illumination pass (GI) as well as the Raw GI pass (GI Raw) itself.