Adding a Matte Drawing to an Effect

Some effects can use, or even require the use of a matte layer. The matte layer is a drawing that determines the area that the effect affects.

For example, a Cutter effect needs to be connected to a matte layer, because it uses the drawing in the matte layer to determine which part of the drawing to cut out. However, a Colour-Scale effect can be used without a matte layer, in which case it will affect the colour of all of the drawing it is connected to, but if it is connected to a matte layer, it will only affect the colours of the part of the drawing that is covered by the matte drawing.

In the Node view, effects and nodes that require a matte layer will always have a matte port at their left. Effects and nodes that can use a matte layer, but which don't require it, will have their matte port hidden by default, and it will appear if you bring a connection cable near their left edge.

TIP: The same mechanic works with Drawing nodes. Although they do not have a matte port by default, but if you connect a drawing or a composite near their left edge, a matte port will appear. When a Drawing node is connected to a matte, the part of the drawing covered by the matte is cut out from that drawing, which is the same as if the drawing was connected to a Cutter node—see About Masking and Cutting Parts of Elements in your Scenes.