Source: \interaction\InteractionData.js

    import * as core from '../core';

/**
 * Holds all information related to an Interaction event
 *
 * @class
 * @memberof PIXI.interaction
 */
export default class InteractionData
{
    /**
     *
     */
    constructor()
    {
        /**
         * This point stores the global coords of where the touch/mouse event happened
         *
         * @member {PIXI.Point}
         */
        this.global = new core.Point();

        /**
         * The target DisplayObject that was interacted with
         *
         * @member {PIXI.DisplayObject}
         */
        this.target = null;

        /**
         * When passed to an event handler, this will be the original DOM Event that was captured
         *
         * @member {Event}
         */
        this.originalEvent = null;

        /**
         * Unique identifier for this interaction
         *
         * @member {number}
         */
        this.identifier = null;
    }

    /**
     * This will return the local coordinates of the specified displayObject for this InteractionData
     *
     * @param {PIXI.DisplayObject} displayObject - The DisplayObject that you would like the local
     *  coords off
     * @param {PIXI.Point} [point] - A Point object in which to store the value, optional (otherwise
     *  will create a new point)
     * @param {PIXI.Point} [globalPos] - A Point object containing your custom global coords, optional
     *  (otherwise will use the current global coords)
     * @return {PIXI.Point} A point containing the coordinates of the InteractionData position relative
     *  to the DisplayObject
     */
    getLocalPosition(displayObject, point, globalPos)
    {
        return displayObject.worldTransform.applyInverse(globalPos || this.global, point);
    }
}