phaser/v3/merge/gameobjects/components/Delta.js
2016-11-23 00:17:46 +00:00

68 lines
1.5 KiB
JavaScript

/**
* @author Richard Davey <rich@photonstorm.com>
* @copyright 2016 Photon Storm Ltd.
* @license {@link https://github.com/photonstorm/phaser/blob/master/license.txt|MIT License}
*/
/**
* The Delta component provides access to delta values between the Game Objects current and previous position.
*
* @class
*/
Phaser.Component.Delta = function () {};
Phaser.Component.Delta.prototype = {
/**
* Returns the delta x value. The difference between world.x now and in the previous frame.
*
* The value will be positive if the Game Object has moved to the right or negative if to the left.
*
* @property {number} deltaX
* @readonly
*/
deltaX: {
get: function() {
return this.world.x - this.previousPosition.x;
}
},
/**
* Returns the delta y value. The difference between world.y now and in the previous frame.
*
* The value will be positive if the Game Object has moved down or negative if up.
*
* @property {number} deltaY
* @readonly
*/
deltaY: {
get: function() {
return this.world.y - this.previousPosition.y;
}
},
/**
* Returns the delta z value. The difference between rotation now and in the previous frame.
*
* @property {number} deltaZ - The delta value.
* @readonly
*/
deltaZ: {
get: function() {
return this.rotation - this.previousRotation;
}
}
};