Apple Motion 3 - Manual (Page 1065)

Chapter 12 Using Shapes and Masks 1065
Min Pressure: Adjusts the minimum threshold of pressure sensitivity. Pressure values
below the minimum value are remapped to 0. For Opacity and Width, that section of
the stroke does not appear. For Spacing, Angle, and Jitter, the values will not be
modified. If the Min and Max pressure are plotted on a graph, Min Pressure represents
the minimum value, or 0. The area of the graph between Min and Max is remapped to
the output values.
Max Pressure: Adjusts the maximum threshold of pressure sensitivity. Pressure values
above the maximum value are remapped to 1. For Opacity, Width, Spacing, Angle, and
Jitter, that section of the stroke will have the greatest effect. If the Min and Max
pressures are plotted on a graph, Max Pressure represents the maximum value, or 1. The
area of the graph between Min and Max is remapped to the output values.
Scale: Determines the magnitude of the effect. Defines the output range for the dabs
based on the mapped values between minimum (0) and maximum (1) pressure,
multiplied by the value defined in the slider (or value field). This amount is then applied
to the channel (width, opacity, and so on) by multiplying (for Width, Opacity, Spacing,
and Jitter) or adding (for Angle). This control is independent of the Scale parameter in
the Stroke pane.
Invert: This checkbox inverts the attributes of the stroke created by the behavior. For
example, if pen pressure is set to affect the opacity of the stroke, transparent areas of
the stroke become more opaque and opaque areas become more transparent when
the checkbox is selected.
Apply Pen Speed
When using a stylus or mouse to create paint strokes, this behavior allows you to affect
the width, opacity, spacing, angle, or jitter of the paint stroke based on the speed of
your pen strokes.
Note: In the Paint Stroke Tool HUD, you can select how the speed of the stylus affects
the stroke before the stroke is created. Applying the Pen Speed behavior allows you to
affect more than one parameter (such as Opacity, Width, or Jitter) of the stroke using
the same pressure data. The Pen Speed parameter also appears in the Advanced pane
of the Shape Inspector.
Apply To: Use this pop-up menu to select how your paint stroke is affected by pen
speed.
 Width: The quicker you move the pen, the more narrow the stroke; the slower you
move the pen, the wider the stroke.
 Opacity: Pen speed affects the opacity of the stroke. The faster you move the pen,
the less opaque the stroke.
 Spacing: The faster you move the pen, the greater the spacing in between the dabs
of the stroke.