This page provides information about the Corona User Property Map.
Overview
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The Corona User Property Map lets you get a user-defined value from a specific object (for example an RGB color value), and then use it to control a property of a material or a texture assigned to that object.
Example uses:
Fancy Bullets
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circle
Create one material. Assign this single material to multiple objects. Change the color of specific objects based on the values specified in their object properties
Create one material and control the brightness of specific objects based on their user properties
Blend two materials using a mask. Then control how this mask is affecting various objects by controlling the opacity of that mask based on the user properties of specific objects