The Composite material node mixes several materials using masks (figure 1). This is much cleaner than using several chained Mix materials. If a mask is not connected, the material's Opacity is used. The first Material pin becomes the base layer.

Figure 1: Composite material Node

Parameters

    • Add Input - Adds a new Material input to the end of the node.
    • Remove Input - Removes the last Material input.
    • Displacement - Displacement for the Composite Material surface.
    • Custom AOV - Writes a mask to the specified custom AOV.
    • Custom AOV Channel - Determines whether the custom AOV is written to a specific color channel (R, G, or B) or to all the color channels.
    • Mat # enabled - To make active or inactive. 
    • Material - The Material input. When several Materials are used, the first Material pin becomes the base layer.
    • Material Mask - Controls the Material’s opacity using an Input map. If a mask is not connected, the Material's opacity is used.