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Point

Package | flash.geom
Class | public class Point
Inheritance | Point Object

Language Version : | ActionScript 3.0

Player Version : | Flash Player 9

The Point object represents a location in a two-dimensional coordinate system, where x represents the horizontal axis and y represents the vertical axis.

The following code creates a point at (0,0):

    var myPoint:Point = new Point();

Methods and properties of the following classes use Point objects:

- BitmapData
- DisplayObject
- DisplayObjectContainer
- DisplacementMapFilter
- Matrix
- Rectangle

You can use the `new Point()` constructor to create a Point object.

View the examples

See also

flash.display.BitmapData
flash.display.DisplayObject
flash.display.DisplayObjectContainer
flash.filters.DisplacementMapFilter
flash.geom.Matrix
flash.geom.Rectangle
Using Point objects

Public Properties
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| Property | Defined By
--- | --- | ---
|  | constructor : Object A reference to the class object or constructor function for a given object instance. | Object
|  | length : Number [read-only] The length of the line segment from (0,0) to this point. | Point
|  | prototype : Object [static] A reference to the prototype object of a class or function object. | Object
|  | x : Number The horizontal coordinate of the point. | Point
|  | y : Number The vertical coordinate of the point. | Point

Public Methods
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| Method | Defined By
--- | --- | ---
|  | Point(x:Number = 0, y:Number = 0) Creates a new point. | Point
|  | add(v:Point):Point Adds the coordinates of another point to the coordinates of this point to create a new point. | Point
|  | clone():Point Creates a copy of this Point object. | Point
|  | distance(pt1:Point, pt2:Point):Number [static] Returns the distance between pt1 and pt2. | Point
|  | equals(toCompare:Point):Boolean Determines whether two points are equal. | Point
|  | hasOwnProperty(name:String):Boolean Indicates whether an object has a specified property defined. | Object
|  | interpolate(pt1:Point, pt2:Point, f:Number):Point [static] Determines a point between two specified points. | Point
|  | isPrototypeOf(theClass:Object):Boolean Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter. | Object
|  | normalize(thickness:Number):void Scales the line segment between (0,0) and the current point to a set length. | Point
|  | offset(dx:Number, dy:Number):void Offsets the Point object by the specified amount. | Point
|  | polar(len:Number, angle:Number):Point [static] Converts a pair of polar coordinates to a Cartesian point coordinate. | Point
|  | propertyIsEnumerable(name:String):Boolean Indicates whether the specified property exists and is enumerable. | Object
|  | setPropertyIsEnumerable(name:String, isEnum:Boolean = true):void Sets the availability of a dynamic property for loop operations. | Object
|  | subtract(v:Point):Point Subtracts the coordinates of another point from the coordinates of this point to create a new point. | Point
|  | toString():String Returns a string that contains the values of the x and y coordinates. | Point
|  | valueOf():Object Returns the primitive value of the specified object. | Object

Property Detail

length | property

`length:Number` [read-only]

Language Version : | ActionScript 3.0

Player Version : | Flash Player 9

The length of the line segment from (0,0) to this point.

Implementation
`public function get length():Number`

See also

Point.polar()

x | property |

`public var x:Number`

Language Version : | ActionScript 3.0

Player Version : | Flash Player 9

The horizontal coordinate of the point. The default value is 0.

See also

Using Point objects

y | property |

`public var y:Number`

Language Version : | ActionScript 3.0

Player Version : | Flash Player 9

The vertical coordinate of the point. The default value is 0.

See also

Using Point objects
Constructor Detail

Point | () | Constructor

`public function Point(x:Number = 0, y:Number = 0)`

Language Version : | ActionScript 3.0

Player Version : | Flash Player 9

Creates a new point. If you pass no parameters to this method, a point is created at (0,0).

Parameters

| `x:Number` (default = `0`)`` — The horizontal coordinate.
| `y:Number` (default = `0`)`` — The vertical coordinate.

Method Detail

add | () | method

`public function add(v:Point):Point`

Language Version : | ActionScript 3.0

Player Version : | Flash Player 9

Adds the coordinates of another point to the coordinates of this point to create a new point.

Parameters

| `v:Point` — The point to be added.

Returns

| `Point` — The new point.

clone | () | method |

`public function clone():Point`

Language Version : | ActionScript 3.0

Player Version : | Flash Player 9

Creates a copy of this Point object.

Returns

| `Point` — The new Point object.

distance | () | method |

`public static function distance(pt1:Point, pt2:Point):Number`

Language Version : | ActionScript 3.0

Player Version : | Flash Player 9

Returns the distance between `pt1` and `pt2`.

Parameters

| `pt1:Point` — The first point.
| `pt2:Point` — The second point.

Returns

| `Number` — The distance between the first and second points.

See also

Using Point objects

equals | () | method |

`public function equals(toCompare:Point):Boolean`

Language Version : | ActionScript 3.0

Player Version : | Flash Player 9

Determines whether two points are equal. Two points are equal if they have the same x and y values.

Parameters

| `toCompare:Point` — The point to be compared.

Returns

| `Boolean` — A value of `true` if the object is equal to this Point object; `false` if it is not equal.

interpolate | () | method |

`public static function interpolate(pt1:Point, pt2:Point, f:Number):Point`

Language Version : | ActionScript 3.0

Player Version : | Flash Player 9

Determines a point between two specified points. The parameter `f` determines where the new interpolated point is located relative to the two end points specified by parameters `pt1` and `pt2`. The closer the value of the parameter `f` is to `1.0`, the closer the interpolated point is to the first point (parameter `pt1`). The closer the value of the parameter `f` is to 0, the closer the interpolated point is to the second point (parameter `pt2`).

Parameters

| `pt1:Point` — The first point.
| `pt2:Point` — The second point.
| `f:Number` — The level of interpolation between the two points. Indicates where the new point will be, along the line between `pt1` and `pt2`. If `f`=1, `pt1` is returned; if `f`=0, `pt2` is returned.

Returns

| `Point` — The new, interpolated point.

normalize | () | method |

`public function normalize(thickness:Number):void`

Language Version : | ActionScript 3.0

Player Version : | Flash Player 9

Scales the line segment between (0,0) and the current point to a set length.

Parameters

| `thickness:Number` — The scaling value. For example, if the current point is (0,5), and you normalize it to 1, the point returned is at (0,1).

See also

length

offset | () | method |

`public function offset(dx:Number, dy:Number):void`

Language Version : | ActionScript 3.0

Player Version : | Flash Player 9

Offsets the Point object by the specified amount. The value of `dx` is added to the original value of x to create the new x value. The value of `dy` is added to the original value of y to create the new y value.

Parameters

| `dx:Number` — The amount by which to offset the horizontal coordinate, x.
| `dy:Number` — The amount by which to offset the vertical coordinate, y.

polar | () | method |

`public static function polar(len:Number, angle:Number):Point`

Language Version : | ActionScript 3.0

Player Version : | Flash Player 9

Converts a pair of polar coordinates to a Cartesian point coordinate.

Parameters

| `len:Number` — The length coordinate of the polar pair.
| `angle:Number` — The angle, in radians, of the polar pair.

Returns

| `Point` — The Cartesian point.

See also

length
Math.round()
Using Point objects

subtract | () | method |

`public function subtract(v:Point):Point`

Language Version : | ActionScript 3.0

Player Version : | Flash Player 9

Subtracts the coordinates of another point from the coordinates of this point to create a new point.

Parameters

| `v:Point` — The point to be subtracted.

Returns

| `Point` — The new point.

toString | () | method |

`public function toString():String`

Language Version : | ActionScript 3.0

Player Version : | Flash Player 9

Returns a string that contains the values of the x and y coordinates. The string has the form `"(x=x, y=y)"`, so calling the `toString()` method for a point at 23,17 would return `"(x=23, y=17)"`.

Returns

| `String` — The string representation of the coordinates.

Examples How to use examples
PointExample.as
The following example uses the PointExample class to create a number of new Point objects at various x,y coordinates and then uses the `trace()` method to output the results of various class methods.

    package {
        import flash.display.Sprite;
        import flash.geom.Point;

        public class PointExample extends Sprite {

            public function PointExample() {
            var point1:Point = new Point();
            trace(point1);  // (x=0, y=0)

            var point2:Point = new Point(6, 8);
            trace(point2); // (x=6, y=8)

            trace(Point.interpolate(point1, point2, 0.5)); // (x=3, y=4)

            trace(Point.distance(point1, point2)); // 10

            trace(point1.add(point2)); // (x=6, y=8)

            var point3:Point = point2.clone();
            trace(point2.equals(point3)); // true

            point3.normalize(2.5);
            trace(point3); // (x=1.5, y=2)

            trace(point2.subtract(point3)); // (x=4.5, y=6)

            trace(point1.offset(2, 3)); //

            var angle:Number = Math.PI * 2 * (30 / 360); // 30°
            trace(Point.polar(4, angle)) // (x=3.464101615137755, y=1.9999999999999998)
            }
        }
    }

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