Attractor
If you apply an Attractor behavior to an object, other objects that lie within the area of
influence move toward it. You can manipulate the strength with which other objects are
attracted, as well as the distance required for attraction to begin.
End of Attractor effect (motion paths shown)
Start of Attractor effect
By default, objects overshoot the object of attraction and bounce around, never coming
to rest. The Drag parameter lets you adjust this behavior, changing whether attracted
objects overshoot and bounce around, or whether they eventually slow down and stop
at the position of the target object.
The Attractor behavior can affect all objects in the Canvas that fall within the area of
attraction, or you can limit its effect to a specific list of objects by using the Affect
parameter.
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The Attractor behavior can also be applied to objects in motion. If you animate the position
of the target object to which you’ve applied the Attractor behavior, all other objects in
the Canvas continue to be attracted to its new position.
Parameters in the Inspector
Affect:
A pop-up menu that limits which objects in your project are affected by the
Attractor behavior. There are three options:
• All Objects: All objects in the Canvas are affected by the Attractor behavior.
• Related Objects: The default setting. Only other objects in the same group as the object
of attraction are affected.
• Specific Objects: Only objects appearing in the Affected Objects list are affected by the
Attractor behavior.
Affected Objects:
A list that appears when Specific Objects is chosen in the Affect pop-up
menu. Drag objects from the Layers list into this list to be affected by the Attractor behavior
when the Specific Objects option is selected in the Affect pop-up menu. To remove an
item from the list, select the item and click Remove.
• Layer: This column lists the name of the layer containing the object.
• Name: This column lists the name of the object.
Strength:
A slider defining the speed with which attracted objects move toward the
target object. With a value of 0, attracted objects don’t move at all. The higher the value,
the faster attracted objects move.
Falloff Type:
A pop-up menu that determines whether the distance defined by the
Influence parameter falls off linearly or exponentially.
• Linear: Object attraction falls off in proportion to the object’s distance.
• Exponential: The closer an object is within the area of influence, the more strongly it
is attracted, and the faster it moves toward the object of attraction.
Falloff Rate:
This value determines how quickly the force of attraction between objects
affected by this behavior falls off. A low Falloff Rate value results in objects quickly getting
up to speed as they move toward the object of attraction. A high Falloff Rate causes
objects to accelerate much more slowly. When set to Exponential, the attraction falls off
more quickly than when set to Linear.
Influence:
A slider that defines the radius of the circle of influence in pixels. Objects that
fall within the area of influence move toward the object of attraction. Objects outside
the area of influence remain in place.
Drag:
A slider that can be used to reduce the distance attracted objects overshoot the
object of attraction. Lower Drag values result in the object overshooting the object of
attraction, moving past and then careening back around toward the target object again
and again. Higher Drag values result in the object coming to rest sooner.
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Include X, Y, and Z:
Buttons that allow you to specify the space in which the object (or
objects) moves toward the target object. For example, when X and Y are enabled, the
object moves in the XY plane; when Y and Z are enabled, the object moves in the YZ
plane.
HUD Controls
The HUD lets you adjust the Affect, Strength, Falloff Type, Falloff Rate, Influence, Drag,
and axis assignment parameters.
Related Behaviors
•
Attracted To
•
Drift Attracted To
•
Drift Attractor
•
Orbit Around
•
Spring
•
Vortex