User Manual

Object ID for ground plane and object set to the same numeric value.
World Position Pass
The World Position Pass, or WPP, is a render pass generated from 3D applications. Each pixel is
assigned the XYZ position where the pixel was generated in the world coordinates. So if the
face from which the pixel was derived in the scene sits at (0,0,0), the resulting pixel will have a
Position value of (0,0,0). If we visualize this as RGB, the pixel will be black. If a face sits at (1,0,0)
in the original scene, the resulting RGB pixel will be red. Due to the huge range of possible
positions in a typical 3D scene, and 7⁄8 of those possible positions containing negative
coordinates, the Position channel is always rendered in 32-bit float.
A World Position Pass rendering of a scene with its center at (0,0,0). The actual image is on the left.
3D Scene Input
Nodes that utilize the World Position channel are located under the Position category.
VolumeFog and Z to WorldPos require a camera input matching the camera that rendered the
Position channels, which can either be a Camera3D or a 3D scene containing a camera. Just as
in the Renderer3D, you can choose which camera to use if more than one are in the scene. The
VolumeFog can render without a camera input from the Node Editor if the world space Camera
Position inputs are set to the correct value. VolumeMask does not use a camera input. Nodes
that support the World Position Pass, located under the Position category, offer a Scene input,
which can be either a 3D Camera or a 3D scene containing a camera.
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