import { System } from '../System';
import type { MaskData } from './MaskData';
import type { Renderer } from '../Renderer';
/**
* System plugin to the renderer to manage specific types of masking operations.
*
* @class
* @extends PIXI.System
* @memberof PIXI
*/
export class AbstractMaskSystem extends System
{
protected maskStack: Array<MaskData>;
protected glConst: number;
/**
* @param {PIXI.Renderer} renderer - The renderer this System works for.
*/
constructor(renderer: Renderer)
{
super(renderer);
/**
* The mask stack
* @member {PIXI.MaskData[]}
*/
this.maskStack = [];
/**
* Constant for gl.enable
* @member {number}
* @private
*/
this.glConst = 0;
}
/**
* gets count of masks of certain type
* @returns {number}
*/
getStackLength(): number
{
return this.maskStack.length;
}
/**
* Changes the mask stack that is used by this System.
*
* @param {PIXI.MaskData[]} maskStack - The mask stack
*/
setMaskStack(maskStack: Array<MaskData>): void
{
const { gl } = this.renderer;
const curStackLen = this.getStackLength();
this.maskStack = maskStack;
const newStackLen = this.getStackLength();
if (newStackLen !== curStackLen)
{
if (newStackLen === 0)
{
gl.disable(this.glConst);
}
else
{
gl.enable(this.glConst);
this._useCurrent();
}
}
}
/**
* Setup renderer to use the current mask data.
* @private
*/
protected _useCurrent(): void
{
// OVERWRITE;
}
/**
* Destroys the mask stack.
*
*/
destroy(): void
{
super.destroy();
this.maskStack = null;
}
}