Apple Motion 5.1.1 - Manual (Page 900)

Chapter 20 Shapes, masks, and paint strokes 900
•
Add: Removes all pixels from areas outside the mask shape. Each new mask adds more
transparency, letting more of the underlying image show through. The Add blend mode (the
default for new masks) is useful for adding back regions of an image that other masks are
cutting out or when masking multiple areas that do not intersect in a single image. In the
following example, both the rectangle and circle masks remove areas outside of the mask
shapes, revealing the underlying black canvas.
If the layer contains an alpha channel, a mask set to Add mode reveals only the masked
section of the original alpha channel.
Original alpha channel of butterfly clip Circle mask set to default. Add mode applied
to butterfly clip.
Note: To display the rest of a masked layer so you can trace it to create a second mask, turn off
the first mask in the Layers list or Timeline. The outline of the first mask remains visible, even
though it’s no longer affecting the layer’s transparency.
•
Subtract: Removes all pixels from the area inside the mask shape, effectively punching a hole
in the image. In the following example, the rectangle and circle masks punch a hole through
the blue gradient object, revealing the underlying black Canvas.
67% resize factor