User Manual

Volume Fog [VLF]
The Volume Fog node
Volume Fog Node Introduction
The Volume Fog node is used to create sophisticated volumetric fog on images containing XYZ
Position channels.
As opposed to 3D-rendered volumetric fog, it works on 2D images and delivers much faster
results and interactive feedback when setting up the fog. See the “WPP Concept” section at the
end of this chapter for further explanation of how this technology works and to learn about the
required imagery.
Basic Node Setup
The Volume Fog node takes an image input; in the example below, it is a Renderer 3D with
World Position enabled in the output channels. Another input is the 3D scene, which contains
the camera. A Fast Noise node generates the fog texture.
Volume Fog Node Structure
A 3D scene and a rendered scene connected to Volume Fog
Inputs
The following inputs appear on the Volume Fog node in the Node Editor.
–
Image: The orange input accepts the primary image where the fog will be applied.
This image contains a World Position Pass in the XYZ Position channels.
–
Fog Image: The green Fog image input is for creating volumetric fog with varying
depth and extent; a 2D image can be connected here. A good starting point is to
use a Fast Noise at a small resolution of 256 x 256 pixels.
–
Effect Mask: The blue input is for a mask shape created by polylines, basic primitive
shapes, paint strokes, or bitmaps from other tools. Connecting a mask to this input
limits the fog to certain areas.
–
Scene Input: The magenta scene input accepts a 3D scene containing a 3D Camera.
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