Overview of Final Gather
- secondary diffuse bounces
- point density
- primary diffuse scale
- secondary diffuse scale
- point interpolation
Final Gathering is considered a view-dependent global illumination process, meaning that the render is calculated based on the rendering camera point-of-view. Whenever the camera moved, the Final Gather process must be recalculated. In Final Gather, the rendering camera shoots final gather rays into the environment and detects how the light is reacting to surfaces to create the indirect lighting effect. The initial set of rays sent from the camera evaluate the scene, searching for areas of high contrast to determine where it will place on the geometry the user specified Final Gather sample points.
This is different from global illumination, in that global illumination uses lights that shoot photons into an environment. In this case, the camera is creating the Final Gathering points.
Sec. Diffuse Bounces: the number of times a secondary ray bounces. Secondary bounces are disabled if Global Illumination is turned on, as GI secondary bounces are then used.
Accuracy: the number of secondary rays being sent out after a ray hits its initial point
Point Density: the initial number of Final Gather point samples created by each ray
Point Interpolation: the number of sample points that are blended together to smooth out “splotchiness”. Excessive use will create a loss of detail.
Primary Diffuse Scale: multiplier to brighten the effect of the initial bounce
Secondary Diffuse Scale: multiplier to brighten the effect of the secondary bounces. Secondary bounces are disabled if Global Illumination is turned on, as GI secondary bounces are then used.