The Position channel outputs a representation of the position of each point in the image. This is useful for compositing purposes, i.e. when you need to select all the surfaces that are close to the ground floor (to affect them with certain adjustment), or all of them near the camera. Maxwell can measure that positions regarding two different coordinates systems:
- World coordinates
- Camera coordinates
these positions in either World or Camera coordinates.
Position channel in World coordinates
This mode analyzes the position of each point in the scene regarding in regards to the World coordinates axis and origin. This information is useful in compositing when you need to perform adjustments dependent on the World position of a surface (i.e. near the ground plane or above other objects to mimic a fog effect, etc).
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This mode analyzes the position of each point in the scene regarding the Camera origin and its local axis. This information is useful in compositing when you need to perform adjustments dependent on the Camera position of a surface (i.e. distant objects versus near objects, etc).
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