Definition
A background is a 2D visual placed behind the objects in the 3D world. It does not move when you navigate in the 3D world, but remains stationary with regard to the screen.
Backgrounds are associated with camera sensors. For more information on how backgrounds are created and applied, see Backgrounds (Editor) and Sensors.
In Matter, two types of backgrounds are available:
Environment type: displays the lighting environment used to calculate the reflections and the diffuse lighting of the materials.
Gradient type: replaces the uniform background of a view with a color gradient or with an image. The gradient is defined by a Start color and an End color, which are respectively associated with the top and bottom edges of the viewing zone.
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Left: Gradient type background - Right: Environment type background