import type { IPointData } from './IPointData';
import type { IPoint } from './IPoint';
export interface ObservablePoint extends GlobalMixins.Point, IPoint {}
/**
* The ObservablePoint object represents a location in a two-dimensional coordinate system, where `x` represents
* the position on the horizontal axis and `y` represents the position on the vertical axis.
*
* An `ObservablePoint` is a point that triggers a callback when the point's position is changed.
* @memberof PIXI
*/
export class ObservablePoint<T = any> implements IPoint
{
/** The callback function triggered when `x` and/or `y` are changed */
public cb: (this: T) => any;
/** The owner of the callback */
public scope: any;
_x: number;
_y: number;
/**
* Creates a new `ObservablePoint`
* @param cb - callback function triggered when `x` and/or `y` are changed
* @param scope - owner of callback
* @param {number} [x=0] - position of the point on the x axis
* @param {number} [y=0] - position of the point on the y axis
*/
constructor(cb: (this: T) => any, scope: T, x = 0, y = 0)
{
this._x = x;
this._y = y;
this.cb = cb;
this.scope = scope;
}
/**
* Creates a clone of this point.
* The callback and scope params can be overridden otherwise they will default
* to the clone object's values.
* @override
* @param cb - The callback function triggered when `x` and/or `y` are changed
* @param scope - The owner of the callback
* @returns a copy of this observable point
*/
clone(cb = this.cb, scope = this.scope): ObservablePoint
{
return new ObservablePoint(cb, scope, this._x, this._y);
}
/**
* Sets the point to a new `x` and `y` position.
* If `y` is omitted, both `x` and `y` will be set to `x`.
* @param {number} [x=0] - position of the point on the x axis
* @param {number} [y=x] - position of the point on the y axis
* @returns The observable point instance itself
*/
set(x = 0, y = x): this
{
if (this._x !== x || this._y !== y)
{
this._x = x;
this._y = y;
this.cb.call(this.scope);
}
return this;
}
/**
* Copies x and y from the given point (`p`)
* @param p - The point to copy from. Can be any of type that is or extends `IPointData`
* @returns The observable point instance itself
*/
copyFrom(p: IPointData): this
{
if (this._x !== p.x || this._y !== p.y)
{
this._x = p.x;
this._y = p.y;
this.cb.call(this.scope);
}
return this;
}
/**
* Copies this point's x and y into that of the given point (`p`)
* @param p - The point to copy to. Can be any of type that is or extends `IPointData`
* @returns The point (`p`) with values updated
*/
copyTo<T extends IPoint>(p: T): T
{
p.set(this._x, this._y);
return p;
}
/**
* Accepts another point (`p`) and returns `true` if the given point is equal to this point
* @param p - The point to check
* @returns Returns `true` if both `x` and `y` are equal
*/
equals(p: IPointData): boolean
{
return (p.x === this._x) && (p.y === this._y);
}
// #if _DEBUG
toString(): string
{
return `[@pixi/math:ObservablePoint x=${0} y=${0} scope=${this.scope}]`;
}
// #endif
/** Position of the observable point on the x axis. */
get x(): number
{
return this._x;
}
set x(value: number)
{
if (this._x !== value)
{
this._x = value;
this.cb.call(this.scope);
}
}
/** Position of the observable point on the y axis. */
get y(): number
{
return this._y;
}
set y(value: number)
{
if (this._y !== value)
{
this._y = value;
this.cb.call(this.scope);
}
}
}