Shapes, masks, and paint strokes overview
Shapes, masks, and paint strokes are vector-based layers that you create in Motion.
Shapes are primarily used to create visual elements in a composition. You can use a single shape as a background or colored graphic in a composition, or you can create elaborate illustrations that combine many shapes. Shapes work like any other layer. But unlike an image or video clip that you import as a layer, a shape layer is created in Motion, either by adding a premade shape from the Library or by drawing a custom shape in the Canvas. There are two categories of custom shapes: simple shapes drawn as a rectangle or ellipse, and complex shapes drawn point by point as a Bezier or B-Spline shape. Each control point in a complex shape defines some sort of corner or curve, and the actual spline that makes up the shape connects these control points together like a connect-the-dots drawing.
Masks are a special type of shape used to create regions of transparency in layers. Although shapes work as layers by themselves, masks must be assigned to an image layer to have an effect. For example, if you have a picture in which you want to isolate the foreground subject, you can create a mask to cut out the background. As with shapes, there are two categories of masks: simple masks drawn as a rectangle or ellipse, and complex masks drawn point by point in the Canvas as Bezier or B-Spline shapes.
Like shapes, paint strokes are used to create visual elements in a composition. Paint strokes are drawn in the Canvas in a single, continuous movement. You can use a stylus and graphics tablet to draw paint strokes in a fluid fashion. Or you can use a mouse or Multi-Touch device to draw paint strokes.
To begin using paint strokes, see Paint strokes overview.
As with all objects in Motion, shapes, masks, and paint strokes can be edited or animated by keyframing their parameters or by applying behaviors. Additionally, the Shape Behaviors category contains behaviors designed specifically to animate shapes, including a behavior to sequence effects over the length of a paint stroke. For more information on using the Shape behaviors, see Shape behaviors overview.