Phaser Source: src/plugins/path/PathPoint.js

# Source: src/plugins/path/PathPoint.js

    /**
    * @author       Richard Davey <rich@photonstorm.com>
    * @author       Pete Baron <pete@photonstorm.com>
    * @copyright    2016 Photon Storm Ltd.
    * @license      {@link https://github.com/photonstorm/phaser/blob/master/license.txt|MIT License}
    */

    /**
    * The PathPoint class contains data and functions for each point on a Path.
    *
    * @class Phaser.PathPoint
    * @constructor
    * @param {number} x - The x coordinate of the PathPoint.
    * @param {number} y - The y coordinate of the PathPoint.
    * @param {number} vx - The x coordinate of the tangent vector to create the curve from.
    * @param {number} vy - The y coordinate of the tangent vector to create the curve from.
    * @param {number} [speed=1] - The speed multiplier for PathFollowers on this Path segment.
    * @param {object} [data] - The data associated with this point, e.g.: { type: PathPoint.DATA_VALUE, value: XXX }
    * @param {Phaser.Path} [branchPath] - A branched path which is attached to this point.
    * @param {number} [branchPointIndex] - The index where the branch is attached to on the new path.
    */
    Phaser.PathPoint = function (x, y, vx, vy, speed, data, branchPath, branchPointIndex) {

        if (speed === undefined) { speed = 1; }
        if (data === undefined) { data = { type: 0, value: 0 }; }
        if (branchPath === undefined) { branchPath = null; }
        if (branchPointIndex === undefined) { branchPointIndex = 0; }

        /**
        * @property {number} x - The x coordinate of the PathPoint.
        */
        this.x = x;

        /**
        * @property {number} y - The y coordinate of the PathPoint.
        */
        this.y = y;

        /**
        * @property {number} vx - The x coordinate of the tangent vector to create the curve from.
        */
        this.vx = vx;

        /**
        * @property {number} vy - The y coordinate of the tangent vector to create the curve from.
        */
        this.vy = vy;

        /**
        * @property {number} speed - The speed multiplier for PathFollowers on this path segment.
        */
        this.speed = speed;

        /**
        * @property {object} data - Data associated with this point eg: { type: PathPoint.DATA_VALUE, value: XXX }
        */
        this.data = data;

        /**
        * @property {Phaser.Path} branchPath - A branched path which is attached at this point.
        */
        this.branchPath = branchPath;

        /**
        * @property {number} branchPointIndex - The index where the branch is attached to on the new path.
        */
        this.branchPointIndex = branchPointIndex;

        /**
        * @property {number} branchType - The branch type of the path this point is on. Either 0 (attached) or 1 (joined)
        */
        this.branchType = 0;

        /**
        * @property {number} curve - Once the Hermite curve is calculated, store it to avoid recalculation later.
        * @protected
        */
        this.curve = null;

        /**
        * @property {boolean} active - Is this point a selected (or active) point?
        * @warn For Path Editor use only
        */
        this.active = false;

        /**
        * @property {array} controlPoints - A list of Phaser.Point objects representing the control points on the segment.
        * @warn For Path Editor use only
        */
        this.controlPoints = null;

    };

    Phaser.PathPoint.prototype.constructor = Phaser.PathPoint;

    /**
    * @constant
    * @type {number}
    */
    Phaser.PathPoint.DATA_NONE = 0;

    /**
    * @constant
    * @type {number}
    */
    Phaser.PathPoint.DATA_PAUSE = 1;

    /**
    * @constant
    * @type {number}
    */
    Phaser.PathPoint.DATA_VALUE = 2;

    /**
    * @constant
    * @type {number}
    */
    Phaser.PathPoint.DATA_COUNTER = 3;

    Phaser.PathPoint.prototype = {

        /**
        * Sets the x, y and optionally vx and vy properties of this PathPoint.
        *
        * @method Phaser.PathPoint#setTo
        * @param {number} x - The x coordinate of the PathPoint.
        * @param {number} y - The y coordinate of the PathPoint.
        * @param {number} [vx] - The x coordinate of the tangent vector to create the curve from.
        * @param {number} [vy] - The y coordinate of the tangent vector to create the curve from.
        * @return {Phaser.PathPoint} This object.
        */
        setTo: function (x, y, vx, vy) {

            this.x = x;
            this.y = y;

            if (vx !== undefined)
            {
                this.vx = vx;
            }

            if (vy !== undefined)
            {
                this.vy = vy;
            }

            //  Invalidate the pre-calculated curve to force it to recalculate with these new settings
            this.curve = null;

            return this;

        },

        /**
        * Sets the tangent vector properties of this PathPoint.
        *
        * @method Phaser.PathPoint#setTangent
        * @param {number} vx - The x coordinate of the tangent vector to create the curve from.
        * @param {number} vy - The y coordinate of the tangent vector to create the curve from.
        * @return {Phaser.PathPoint} This object.
        */
        setTangent: function (vx, vy) {

            this.vx = vx;
            this.vy = vy;

            //  Invalidate the pre-calculated curve to force it to recalculate with these new settings
            this.curve = null;

            return this;

        },

        /**
        * Creates a clone of this PathPoint object.
        *
        * @method Phaser.PathPoint#clone
        * @param {Phaser.PathPoint} [out] - An optional PathPoint object into which this object is cloned. If no object is provided a new PathPoint is created.
        * @return {Phaser.PathPoint} A clone of this PathPoint.
        */
        clone: function (out) {

            if (out === undefined) { out = new Phaser.PathPoint(); }

            return out.copy(this);

        },

        /**
        * Copies all of the values from the given PathPoint object into this PathPoint.
        * The source PathPoint is untouched by this operation.
        *
        * @method Phaser.PathPoint#copy
        * @param {Phaser.PathPoint} source - The PathPoint object to copy the values from.
        * @return {Phaser.PathPoint} This PathPoint object.
        */
        copy: function (source) {

            this.x = source.x;
            this.y = source.y;
            this.vx = source.vx;
            this.vy = source.vy;
            this.speed = source.speed;
            this.data = source.data;
            this.branchPath = source.branchPath;
            this.branchPointIndex = source.branchPointIndex;
            this.curve = null;
            this.active = source.active;

            return this;

        },

        /**
        * Compare this PathPoint with another PathPoint object and return `true`
        * if they have the same `x`, `y` and `speed` properties, after taking the optional
        * offset values into consideration.
        *
        * @method Phaser.PathPoint#equals
        * @param {Phaser.PathPoint} pathPoint - The PathPoint to compare against this PathPoint.
        * @param {number} [offsetX=0] - A value to apply to the x coordinate before comparison.
        * @param {number} [offsetY=0] - A value to apply to the y coordinate before comparison.
        * @return {boolean} True if the two PathPoint objects match, after the offsets are applied, or false if they don't.
        */
        equals: function (pathPoint, offsetX, offsetY) {

            if (offsetX === undefined) { offsetX = 0; }
            if (offsetY === undefined) { offsetY = 0; }

            return (this.x === pathPoint.x + offsetX &&
                    this.y === pathPoint.y + offsetY &&
                    this.speed === pathPoint.speed);

        },

        /**
        * Serializes this PathPoint into a JSON object and returns it.
        *
        * @method Phaser.PathPoint#toJSON
        * @return {Object} A JSON object representing this PathPoint.
        */
        toJSON: function () {

            return {
                x: this.x,
                y: this.y,
                vx: this.vx,
                vy: this.vy,
                speed: this.speed,
                data: this.data,
                branchPath: !!this.branchPath ? this.branchPath.name : null,
                branchPointIndex: this.branchPointIndex,
                branchType: this.branchType
            };

        }

    };