Indirect Illumination: Final Gather vs. Global Illumination
If you're familiar with rendering, you're likely familiar with Global Illumination (GI) and Final Gather (FG). These two algorithms are the key components to simulating realistic indirect illumination like you would see in the real world. Without these two techniques the lighting in the CG environments would look unrealistic and extremely flat. So if both GI and FG simulate indirect illumination what is the difference between the two and which one should you be using for your 3D scenes? Despite the fact that both methods are there to achieve relatively the same goal, there are actually differences between the two and may be times when you would want to use one over the other. Let's take a close look at each method and help you determine if one method of simulating indirect illuminating is better than the other.