Volumetric Lights
Volumetric light sources allow you to see beams of light by simulating light scattering through the air. All lights can be marked as volumetrics. But in order to use this feature, you’ll need to enable it in the Renderer Settings.
In the rendering settings of volumetric light, you’ll see Samples
parameter that lets you control its visual fidelity. Making it too high will affect the performance.
There’s also a Max Scattering Distance
parameter that allows you to set a distance from camera beyond which volumetric light effects won’t be calculated.
Note
Volumetric lights can also account for translucent shadows. If translucent shadows are enabled, a volumetric light will increase GPU memory usage.
Volumetric Fog
In the renderer settings, there’s also an option to enable fog for volumetric lights.
If it is enabled, the fog created by lights will be animated. You can control the animation speed by using Speed
parameter.