Instruction Manual

Chapter 20 Shapes, masks, and paint strokes 889
Use the mask tools to create dierent shapes with which to mask a layer or group. There are ve
mask tools available that are analogous to the ve shape-drawing tools covered earlier in this
chapter:
•
Rectangle Mask tool
•
Circle Mask tool
•
Freehand Mask tool (used like the Paint Stroke tool)
•
Bezier Mask tool
•
B-Spline Mask tool
Note: You can also use an Image Mask to mask a layer. For more information, see Image masks
overview on page 902.
Important: A mask cannot be applied to a nonattened 3D group. (To atten a 3D group,
select the Flatten checkbox in the Group Inspector.) A mask can be applied to a layer in a 3D
group. To add a mask to a layer that has been manipulated in 3D space, use the Isolate button.
Masks cannot be manipulated in 3D space. For example, the Position parameter for a mask
only includes the X and Y position parameters, but not the Z position parameter; the Rotation
parameter only includes Z, but not X or Y. For more information, see Mask objects in a 3D
project on page 891.
Drawing and editing masks using these tools works identically to drawing and editing shapes.
The main dierence is that while drawing a shape creates a new layer in your project, masks
must be drawn on top of another layer in your project. After you draw a mask, it is nested in
the specic layer or group for which it was created, in the Layers list and Timeline. When a mask
is attached to a layer, a mask icon appears to the right of the name of the layer. Turn the mask
display on or o by clicking this icon.
Click the mask
icon to turn mask
display on or off.
Note: Masks created for one layer can be copied or moved to other layers.
Important: When a mask is applied to a 2D or attened 3D group, the group is rasterized. For
more information, see Groups and rasterization on page 1045.
Create a mask
Masks can be created on any layer in the Motion project.
67% resize factor