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Maxwell Render's materials are made up of different "components" which are organized into folders (Layers). A folder Each Layer can hold one Coating, one Emitter, one Displacement components, and one or more BSDF components (BSDF are is the main material definition), plus one Coating (varnish), one Emitter and/or one Displacement component.
Each folder in the material editor represents a Layer, which are stacked vertically one on top of the other, similar to layers in a 2D image editing application. Please see the Stacking Layers section for more information about this.
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