Global Illumination

 Pretty image right well this is just what Global Illumination looks like in the CryEngine 3 which is rendered in real-time.

WHAT IS GLOBAL ILLUMINATION

Global Illumination, in computer graphics, is the general name givens to a group of algorithms that are designed to add realistic lighting to 3d scenes. These algorithms not only take into consideration the light coming directly from the light source but also other cases in which light rays from the source are being reflected off other surfaces. You can see an example of this happening below:

 

 Global Illumination is often used to bring realistic lighting and photorealism into video games since images rendered using the global illumination algorithms are often more realistic than images rendered with direct illumination. There are a few types of algorithms used in global illumination some of with are listed below:

• Ambient Occlusion
• Radiosity
• Ray Tracing
• Photon Mapping
• Among others

Some of these algorithms are not the fastest at yielding the results you want but the are the most accurate.

  While Global Illumination is a great technique to make a game more realistic and shiny looking, there are a few draw backs with using it. Unfortunately with Global Illumination images are significantly more expensive and considerably much slower to render which makes them not a good mix for games (especially ray-tracing) despite how nice it can make them look.

 For anyone interest below you will find a tutorial on Global Illumination in Maya for any of you who would like to try it out: