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This does not replace the use of a prelit attribute on objects that need one. However, when used on an object that doesn't have this attribute, the shader will fall into "preview mode". In that case, its color will be shown directly in the beauty RGBA layer without any interaction with the other objects in the scene. In particular, since its color is presumed to already include some light and shadows, it will prevent the surface from being shaded a second time, thus showing a more accurate depiction of the data that will be send sent to the relighting system.
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