| Package | com.greensock.motionPaths |
| Class | public class LinePath2D |
| Inheritance | LinePath2D  MotionPath flash.display.Shape |
progress property, a value between 0 and 1 where 0 is at the beginning of the path,
0.5 is in the middle, and 1 is at the very end. To tween a PathFollower along the path, simply tween its
progress property. To tween ALL of the followers on the path at once, you can tween the
LinePath2D's progress property which performs better than tweening every PathFollower's
progress property individually. PathFollowers automatically wrap so that if the
progress value exceeds 1 it continues at the beginning of the path, meaning that tweening
its progress from 0 to 2 would have the same effect as tweening it from 0 to 1 twice
(it would appear to loop).
Since LinePath2D extends the Shape class, you can add an instance to the display list to see a line representation
of the path drawn which can be particularly helpful during the production phase. Use lineStyle()
to adjust the color, thickness, and other attributes of the line that is drawn (or set the LinePath2D's
visible property to false or don't add it to the display list if you don't want to see the line
at all). You can also adjust all of its properties like scaleX, scaleY, rotation, width, height, x,
and y. That means you can tween those values as well to achieve very dynamic, complex effects
with ease.
import com.greensock.*;
import com.greensock.easing.*;
import com.greensock.motionPaths.*;
import flash.geom.Point;
//create a LinePath2D with 5 Points
var path:LinePath2D = new LinePath2D([new Point(0, 0),
new Point(100, 100),
new Point(350, 150),
new Point(50, 200),
new Point(550, 400)]);
//add it to the display list so we can see it (you can skip this if you prefer)
addChild(path);
//create an array containing 30 blue squares
var boxes:Array = [];
for (var i:int = 0; i < 30; i++) {
boxes.push(createSquare(10, 0x0000FF));
}
//distribute the blue squares evenly across the entire path and set them to autoRotate
path.distribute(boxes, 0, 1, true);
//put a red square exactly halfway through the 2nd segment
path.addFollower(createSquare(10, 0xFF0000), path.getSegmentProgress(2, 0.5));
//tween all of the squares through the path once (wrapping when they reach the end)
TweenMax.to(path, 20, {progress:1});
//while the squares are animating through the path, tween the path's position and rotation too!
TweenMax.to(path, 3, {rotation:180, x:550, y:400, ease:Back.easeOut, delay:3});
//method for creating squares
function createSquare(size:Number, color:uint=0xFF0000):Shape {
var s:Shape = new Shape();
s.graphics.beginFill(color, 1);
s.graphics.drawRect(-size / 2, -size / 2, size, size);
s.graphics.endFill();
this.addChild(s);
return s;
}
NOTES
progress
property which will provide better performance than tweening each follower independently.Copyright 2010-2013, GreenSock. All rights reserved. This work is subject to the terms in http://www.greensock.com/terms_of_use.html or for Club GreenSock members, the software agreement that was issued with the membership.
| Property | Defined By | ||
|---|---|---|---|
| autoUpdatePoints : Boolean If true, the LinePath2D will analyze every Point whenever it renders to see if any Point's x or y value has changed, thus making it possible to tween them dynamically. | LinePath2D | ||
 | followers : Array [read-only] Returns an array of all PathFollower instances associated with this path | MotionPath | |
| height : Number [override] | MotionPath | |
| points : Array The array of Points through which the LinePath2D is drawn. | LinePath2D | ||
| progress : Number
A value between 0 and 1 that can be used to move all followers along the path. | MotionPath | |
| rawProgress : Number
Identical to progress except that the value is not re-interpolated between 0 and 1. | MotionPath | |
| rotation : Number [override] | MotionPath | |
| scaleX : Number [override] | MotionPath | |
| scaleY : Number [override] | MotionPath | |
| targets : Array [read-only] Returns an array of all target instances associated with the PathFollowers of this path | MotionPath | |
| totalLength : Number [read-only] Total length of the LinePath2D as though it were stretched out in a straight, flat line. | LinePath2D | ||
| visible : Boolean [override] | MotionPath | |
| width : Number [override] | MotionPath | |
| x : Number [override] | MotionPath | |
| y : Number [override] | MotionPath | |
| Method | Defined By | ||
|---|---|---|---|
LinePath2D(points:Array = null, x:Number = 0, y:Number = 0, autoUpdatePoints:Boolean = false)
Constructor
| LinePath2D | ||
| addFollower(target:*, progress:Number = 0, autoRotate:Boolean = false, rotationOffset:Number = 0):PathFollower
Adds a follower to the path, optionally setting it to a particular progress position. | MotionPath | |
appendMultiplePoints(points:Array):void
Appends multiple Points to the end of the points array. | LinePath2D | ||
appendPoint(point:Point):void
Adds a Point to the end of the current LinePath2D (essentially redefining its end point). | LinePath2D | ||
| distribute(targets:Array = null, min:Number = 0, max:Number = 1, autoRotate:Boolean = false, rotationOffset:Number = 0):void
Distributes objects evenly along the MotionPath. | MotionPath | |
getClosestProgress(target:Object):Number
Finds the closest overall progress value on the LinePath2D based on the
target object's current position (x and y properties). | LinePath2D | ||
| getFollower(target:Object):PathFollower
Returns the PathFollower instance associated with a particular target or null if none exists. | MotionPath | |
getSegment(progress:Number):uint
Finds the segment associated with a particular a progress value along the entire LinePath2D. | LinePath2D | ||
getSegmentProgress(segment:uint, progress:Number):Number
Translates the progress along a particular segment of the LinePath2D to an overall progress
value, making it easy to position an object like "halfway along the 2nd segment of the line". | LinePath2D | ||
insertMultiplePoints(points:Array, index:uint = 0):void
Inserts multiple Points into the points array at a particular index/position. | LinePath2D | ||
insertPoint(point:Point, index:uint = 0):void
Inserts a Point at a particular index value in the points array, similar to splice() in an array. | LinePath2D | ||
| lineStyle(thickness:Number = 1, color:uint = 0x666666, alpha:Number = 1, pixelHinting:Boolean = false, scaleMode:String = none, caps:String = null, joints:String = null, miterLimit:Number = 3, skipRedraw:Boolean = false):void
Sets the line style for the path which you will only see if you add the path to the display list
with something like addChild() and make sure the visible property is true. | MotionPath | |
| removeAllFollowers():void Removes all followers. | MotionPath | |
| removeFollower(target:*):void
Removes the target as a follower. | MotionPath | |
removePoint(point:Point):void
Removes a particular Point instance from the points array. | LinePath2D | ||
removePointByIndex(index:uint):void
Removes the Point that resides at a particular index/position in the points array. | LinePath2D | ||
renderObjectAt(target:Object, progress:Number, autoRotate:Boolean = false, rotationOffset:Number = 0):void [override]
Positions any object with x and y properties on the path at a specific progress position. | LinePath2D | ||
snap(target:Object, autoRotate:Boolean = false, rotationOffset:Number = 0):PathFollower
Allows you to snap an object like a Sprite, Point, MovieClip, etc. | LinePath2D | ||
update(event:Event = null):void [override]
Forces the MotionPath to re-render itself and all of its followers. | LinePath2D | ||
| autoUpdatePoints | property |
Hide Inherited Public Properties
Show Inherited Public Propertiespublic var autoUpdatePoints:Boolean If true, the LinePath2D will analyze every Point whenever it renders to see if any Point's x or y value has changed, thus making it possible to tween them dynamically. Setting autoUpdatePoints to true increases the CPU load due to the extra processing, so only set it to true if you plan to change one or more of the Points' position.
| points | property |
points:Array The array of Points through which the LinePath2D is drawn. IMPORTANT: Changes to the array are NOT automatically applied or reflected in the LinePath2D - just like the filters property of a DisplayObject, you must set the points property of a LinePath2D directly to ensure that any changes are applied internally.
public function get points():Array public function set points(value:Array):void| totalLength | property |
totalLength:Number [read-only] Total length of the LinePath2D as though it were stretched out in a straight, flat line.
public function get totalLength():Number| LinePath2D | () | Constructor |
public function LinePath2D(points:Array = null, x:Number = 0, y:Number = 0, autoUpdatePoints:Boolean = false)Constructor
Parameterspoints:Array (default = null) | |
x:Number (default = 0) | |
y:Number (default = 0) | |
autoUpdatePoints:Boolean (default = false)autoUpdatePoints to true increases the CPU load due to the extra processing, so only set it to true if you plan to change one or more of the Points' position.
|
| appendMultiplePoints | () | method |
public function appendMultiplePoints(points:Array):void
Appends multiple Points to the end of the points array. Identical to
the appendPoint() method, but accepts an array of Points instead of just one.
Parameters
points:Array — An array of Points to append.
|
| appendPoint | () | method |
public function appendPoint(point:Point):voidAdds a Point to the end of the current LinePath2D (essentially redefining its end point).
Parameters
point:Point — A Point describing the local coordinates through which the line should be drawn.
|
| getClosestProgress | () | method |
public function getClosestProgress(target:Object):Number
Finds the closest overall progress value on the LinePath2D based on the
target object's current position (x and y properties). For example,
to position the mc object on the LinePath2D at the spot that's closest to the Point x:100, y:50,
you could do:
path.addFollower(mc, path.getClosestProgress(new Point(100, 50)));
Parameters
target:Object — The target object whose position (x/y property values) are analyzed for proximity to the LinePath2D.
|
Number — The overall progress value describing the position on the LinePath2D that is closest to the target's current position.
|
| getSegment | () | method |
public function getSegment(progress:Number):uintFinds the segment associated with a particular a progress value along the entire LinePath2D. For example, to find which segment is halfway along the LinePath2D:
path.getSegment(0.5);
To find the segment associated with the LinePath2D's current progress, simply omit the
progress parameter:
var curSegment = path.getSegment();
Parameters
progress:Number (default = NaN)progress along the entire LinePath2D (a value between 0 and 1). For example, the midpoint would be getSegment(0.5);.
|
uint — An integer describing the segment number where the first is 1, second is 2, etc.
|
| getSegmentProgress | () | method |
public function getSegmentProgress(segment:uint, progress:Number):Number
Translates the progress along a particular segment of the LinePath2D to an overall progress
value, making it easy to position an object like "halfway along the 2nd segment of the line". For example:
path.addFollower(mc, path.getSegmentProgress(2, 0.5));
Parameters
segment:uint — The segment number of the line. For example, a line defined by 3 Points would have two segments.
| |
progress:Number — The progress along the segment. For example, the midpoint of the second segment would be getSegmentProgress(2, 0.5);.
|
Number — The progress value (between 0 and 1) describing the overall progress on the entire LinePath2D.
|
| insertMultiplePoints | () | method |
public function insertMultiplePoints(points:Array, index:uint = 0):void
Inserts multiple Points into the points array at a particular index/position.
Identical to the insertPoint() method, but accepts an array of points instead of just one.
Parameters
points:Array — An array of Points to insert.
| |
index:uint (default = 0)points array at which the Points should be inserted.
|
| insertPoint | () | method |
public function insertPoint(point:Point, index:uint = 0):void
Inserts a Point at a particular index value in the points array, similar to splice() in an array.
For example, if a LinePath2D instance has 3 Points already and you want to insert a new Point right after the
first one, you would do:
var path:LinePath2D = new LinePath2D([new Point(0, 0),
new Point(100, 50),
new Point(200, 300)]);
path.insertPoint(new Point(50, 50), 1);
Parameters
point:Point — A Point describing the local coordinates through which the line should be drawn.
| |
index:uint (default = 0)points array at which the Point should be inserted.
|
| removePoint | () | method |
public function removePoint(point:Point):void
Removes a particular Point instance from the points array.
Parameters
point:Point — The Point object to remove from the points array.
|
| removePointByIndex | () | method |
public function removePointByIndex(index:uint):void
Removes the Point that resides at a particular index/position in the points array.
Just like in arrays, the index is zero-based. For example, to remove the second Point in the array,
do removePointByIndex(1);
Parameters
index:uint — The index value of the Point that should be removed from the points array.
|
| renderObjectAt | () | method |
override public function renderObjectAt(target:Object, progress:Number, autoRotate:Boolean = false, rotationOffset:Number = 0):void
Positions any object with x and y properties on the path at a specific progress position.
For example, to position mc in the middle of the path, you would do:
myPath.renderObjectAt(mc, 0.5);
Some paths have methods to translate other meaningful information into a progress value, like
for a CirclePath2D you can get the progress associated with the 90-degree position with the
angleToPosition() method like this:
myCircle.renderObjectAt(mc, myCircle.angleToProgress(90));
Parameters
target:Object — The target object to position
| |
progress:Number — The progress value (typically between 0 and 1 where 0 is the beginning of the path, 0.5 is in the middle, and 1 is at the end)
| |
autoRotate:Boolean (default = false)autoRotate is true, the target will automatically be rotated so that it is oriented to the angle of the path. To offset this value (like to always add 90 degrees for example), use the rotationOffset property.
| |
rotationOffset:Number (default = 0)autoRotate is true, this value will always be added to the resulting rotation of the target.
|
| snap | () | method |
public function snap(target:Object, autoRotate:Boolean = false, rotationOffset:Number = 0):PathFollowerAllows you to snap an object like a Sprite, Point, MovieClip, etc. to the LinePath2D by determining the closest position along the line to the current position of the object. It will automatically create a PathFollower instance for the target object and reposition it on the LinePath2D.
Parameters
target:Object — The target object that should be repositioned onto the LinePath2D.
| |
autoRotate:Boolean (default = false)autoRotate is true, the follower will automatically be rotated so that it is oriented to the angle of the path that it is following. To offset this value (like to always add 90 degrees for example), use the rotationOffset property.
| |
rotationOffset:Number (default = 0)autoRotate is true, this value will always be added to the resulting rotation of the target.
|
PathFollower — A PathFollower instance that was created for the target.
|
| update | () | method |
override public function update(event:Event = null):voidForces the MotionPath to re-render itself and all of its followers.
Parameters
event:Event (default = null) |