Macromedia Flash Professional 8 UNLEASHED [Electronic resources]

David Vogeleer, Eddie Wilson, Lou Barber

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The Point Class

The Point class allows you to create two-dimensional points along the horizontal (x) and vertical (y) axes.

It is important when using this class to import it first at the beginning of your script, like this:

import flash.geom.Point;

To instantiate a new instance of the Point class, use this code as a template:

var myPoint:Point = new Point(x, y);

  • x The two-dimensional point on the horizontal axis.

  • y The two-dimensional point on the vertical axis.

Example :

This example will create an instance of the Point class at coordinate (5,5) and send it to the Output panel:

import flash.geom.Point;
var myPoint:Point = new Point(5,5);
trace(myPoint);
//output: (x=5, y=5)

One other property is not a parameter.

Properties

length

Availability : FP:8, AS:1.0

Generic Template : myPoint.length;

Description :

This property will return the length of the line from coordinate (0,0) to the given point.

Example:

This example will create an instance of the Point class at coordinate (5,5) and send the length from (0,0) to the Output panel:

import flash.geom.Point;
var myPoint:Point = new Point(5,5);
trace(myPoint.length);
//output: 7.07106781186548

Methods

add

Availability : FP:8, AS:1.0

Generic Template : myPoint.add(point);

Parameters:

  • point Another Point object to be added to given point.

Returns : Point

The new point will be a combination of the Point object calling the method and

point .

Description:

This method will add another point to the given point to create a new point.

Example:

This example will create an instance of the Point class at coordinate (5,5), add the point (4,4), and TRace the result:

import flash.geom.Point;
var myPoint:Point = new Point(5,5);
var myPoint2:Point = new Point(4,4);
trace(myPoint.add(myPoint2));
//output: (x=9, y=9)

clone

Availability : FP:8, AS:1.0

Generic Template : myPoint.clone();

Returns : Point

This method will return an exact duplicate of the Point object it is being called on.

Description:

This method will create an exact copy of the Point object it is being called upon.

Example:

This example will create a Point object, create a copy, and output that copy:

import flash.geom.Point;
var myPoint:Point = new Point(5,5);
var myPoint2:Point = myPoint.clone();
trace(myPoint2);
//output: (x=5, y=5)

distance

Availability : FP:8, AS:1.0

Generic Template : Point.distance(point1, point2);

Parameters:

  • point1 The first point.

  • point2 The second point.

Returns : Number

The distance between the two points in pixels.

Description:

This method will calculate the distance between two points in two-dimensional space and return it in pixels.

Example:

This example will create two points and trace the distance between them:

import flash.geom.Point;
var myPoint:Point = new Point(5,5);
var myPoint2:Point = new Point(15,20);
trace(Point.distance(myPoint, myPoint2));
//output: 18.0277563773199

equals

Availability : FP:8, AS:1.0

Generic Template : myPoint.equals(point);

Parameters:

  • point The second Point that

    myPoint is being compared to.

Returns : Boolean

If the two points are equal, TRue; otherwise, false.

Description:

This method will determine if the two points are equal to one another (that is, have the same coordinates) and return a Boolean value.

Example:

This example will create three points and TRace whether or not they are equal:

import flash.geom.Point;
var myPoint:Point = new Point(5,5);
var myPoint2:Point = new Point(15,20);
var myPoint3:Point = myPoint.clone();
trace(myPoint.equals(myPoint2));
trace(myPoint.equals(myPoint3));
//output: false
//         true

interpolate

Availability : FP:8, AS:1.0

Generic Template : Point.interpolate(point1, point2, lvl);

Parameters:

  • point1 The first Point.

  • point2 The second.

  • lvl A floating point number between 01 where if 1 is used,

    point2 will be returned, and if 0 is used,

    point1 will be returned.

Returns : Point

A point between the two points.

Description:

This method will determine a Point object that resides between the two points. You can use the

lvl parameter to control how near to either point the new point should be.

Example:

This example will create a point directly between two points:

import flash.geom.Point;
var myPoint:Point = new Point(5,5);
var myPoint2:Point = new Point(15,20);
trace(Point.interpolate(myPoint, myPoint2, .5));
//output: (x=10, y=12.5)

normalize

Availability : FP:8, AS:1.0

Generic Template : myPoint.normalize(length);

Parameters:

  • length The amount to scale the point by.

Description:

This method will normalize a point based on the given

length .

Example:

This example will create a normalized point based on the length of 2:

import flash.geom.Point;
var myPoint:Point = new Point(4,10);
myPoint.normalize(2);
trace(myPoint);
//output: (x=0.742781352708207, y=1.85695338177052)

offset

Availability : FP:8, AS:1.0

Generic Template : myPoint.offset(x, y);

Parameters:

  • x The horizontal amount to offset the point by.

  • y The vertical amount to offset the point by.

Description:

This method will offset a point by the given (x,y) amounts.

Example:

This example will create a Point and then offset it by (4,4):

import flash.geom.Point;
var myPoint:Point = new Point(5,10);
myPoint.offset(4,4);
trace(myPoint);
//output: (x=9, y=14)

polar

Availability : FP:8, AS:1.0

Generic Template : Point.polar(length, angle);

Parameters:

  • length The length coordinate from the polar pair.

  • angle The angle of the polar pair, in radians.

Returns : Point

The Cartesian point from the polar coordinates.

Description:

This method will convert polar coordinates to a Cartesian point.

Example:

This example will create a Cartesian point based on the polar coordinates.

import flash.geom.Point;
var myPoint:Point = Point.polar(10, 45);
trace(myPoint);
//output: (x=5.2532198881773, y=8.50903524534118)

subtract

Availability : FP:8, AS:1.0

Generic Template : myPoint.subtract(point);

Parameters:

  • point The second point to subtract from

    myPoint .

Returns : Point

The newly created point based on the difference between the two given points.

Description:

This method will subtract the second point from the Point calling the method and return a new point.

Example:

This example will create a Point and subtract a second point (4,4) from it:

import flash.geom.Point;
var myPoint:Point = new Point(5,5);
var myPoint2:Point = new Point(4,4);
trace(myPoint.subtract(myPoint2));
//output: (x=1, y=1)

toString

Availability : FP:8, AS:1.0

Generic Template : myPoint.toString();

Returns : String

The coordinates in the form of a string.

Description:

This method will convert the coordinates into a defined string for output.

Example:

This example will create a Point and send the coordinates to the Output panel:

import flash.geom.Point;
var myPoint:Point = new Point(5,5);
trace(myPoint.toString());
//output: (x=5, y=5)