Class DirtyArea

src/scripting/api/Display/Bitmap.ts:6–40

module Display {

  class DirtyArea {
    private _xBegin:number = null;
    private _yBegin:number = null;
    private _xEnd:number = null;
    private _yEnd:number = null;

    public expand(x:number, y:number) {
      this._xBegin = this._xBegin === null ? x : Math.min(this._xBegin, x);
      this._xEnd = this._xEnd === null ? x : Math.max(this._xEnd, x);
      this._yBegin = this._yBegin === null ? y :Math.min(this._yBegin, y);
      this._yEnd = this._xEnd === null ? y :Math.max(this._yEnd, y);
    }

    public asRect():Rectangle {
      if (this.isEmpty()) {
        return new Rectangle(0, 0, 0, 0);
      }
      return new Rectangle(this._xBegin,
        this._yBegin,
        this._xEnd - this._xBegin,
        this._yEnd - this._yBegin);
    }

    public isEmpty():boolean {
      return this._xBegin === null || this._yBegin === null ||
        this._xEnd === null || this._yEnd === null;
    }

    public reset():void {
      this._xBegin = null;
      this._xEnd = null;
      this._yBegin = null;
      this._yEnd = null;
    }
  }

  /**
   * Bitmap AS3 Polyfill class