Drawing masks and shapes using bezier splines, Drawing masks, And shapes using bezier splines – Apple Motion 2 User Manual
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Chapter 12
Using Shapes and Masks
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Bezier splines are good for drawing shapes for illustration. The controls used to
manipulate Bezier splines are similar to those found in many other drawing and
compositing applications, so they may already be familiar to you. Bezier controls lend
themselves to the creation of precise, detailed shapes. Tangent handles adjust the
curvature of the shape on either side of the control point, and this defines the surface
of the shape.
B-Splines can also be used to draw shapes, but unlike Bezier controls, B-Splines are
manipulated using only points—there are no tangent handles. Furthermore, the points
themselves do not lie on the surface of the shape. Instead, each B-Spline control point
is offset from the shape’s surface, pulling that section of the shape towards itself as if it
was a magnet, in order to create a curve. By combining the influence of multiple B-
Spline points, you can create different curves. B-Splines are extremely smooth—by
default, there are no sharp angles in B-Spline shapes, although you can create sharper
curves, if necessary.
Since B-Spline controls are so simple, they’re easy to animate and manipulate. The tools
you use for a particular task are largely a matter of personal preference.
Drawing Masks and Shapes Using Bezier Splines
This section describes how to draw a Bezier shape from scratch. These methods are
identical whether you use the shape or masking tools. This section focuses on drawing
shapes. For more information on drawing masks, see “
Bezier control point
Tangent handles
B-Spline control point
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