Apple Shake 4 - Manual (Page 587)

Chapter 21 Paint 587
Modifying Paint Stroke Parameters
You can also use the Edit Controls tab in the QuickPaint parameters to modify your
strokes.
In the Edit Controls tab, click a brush type in the Tool row to switch brush types. You
can also click the Hard/Soft button to switch between a hard and soft falloff, or change
the stroke type with the Convert Stroke button. Additionally, you can alter or animate
the color, alpha, opacity, brushSize, or aspectRatio parameters of the current stroke.
The startPoint parameter determines the point at which the stroke begins, measured as
a percentage offset from the beginning of the stroke’s path. For example, a startPoint
value of 50 displays a stroke that is half the length of its invisible path. The endPoint
parameter works the same way, but from the other end of the stroke. You can animate
a stroke onscreen, creating a handwriting effect by setting keyframes for the endPoint
from 0 to 100 over several frames. All stroke types can be animated in this way.
Remember that the startPoint and endPoint parameters describe a percentage of the
path. Therefore, if you change control point positions relative to each other, you may
introduce unwanted fluctuations in the line-drawing animation.
The keyFrames parameter (in the Paint Controls subtab) is a placeholder so that
keyframe markers appear in the Time Bar—it has no other interactive function.