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

54 lines
1.7 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 AutoCull Component is responsible for providing methods that check if a Game Object is within the bounds of the World Camera.
* It is used by the InWorld component.
*
* @class
*/
Phaser.Component.AutoCull = function () {};
Phaser.Component.AutoCull.prototype = {
/**
* A Game Object with `autoCull` set to true will check its bounds against the World Camera every frame.
* If it is not intersecting the Camera bounds at any point then it has its `renderable` property set to `false`.
* This keeps the Game Object alive and still processing updates, but forces it to skip the render step entirely.
*
* This is a relatively expensive operation, especially if enabled on hundreds of Game Objects. So enable it only if you know it's required,
* or you have tested performance and find it acceptable.
*
* @property {boolean} autoCull
* @default
*/
autoCull: false,
/**
* Checks if the Game Objects bounds intersect with the Game Camera bounds.
* Returns `true` if they do, otherwise `false` if fully outside of the Cameras bounds.
*
* @property {boolean} inCamera
* @readonly
*/
inCamera: {
get: function() {
if (!this.autoCull && !this.checkWorldBounds)
{
this._bounds.copyFrom(this.getBounds());
this._bounds.x += this.game.camera.view.x;
this._bounds.y += this.game.camera.view.y;
}
return this.game.world.camera.view.intersects(this._bounds);
}
}
};