docs: function AbstractFilter(fragmentSrc, uniforms)
  {
      /**
      * An array of passes - some filters contain a few steps this array simply stores the steps in a liniear fashion.
      * For example the blur filter has two passes blurX and blurY.
      * @property passes
      * @type Array an array of filter objects
      * @private
      */
      this.passes = [this];
  
  
      this.dirty = true;
      this.padding = 0;
  
      /**
      @property uniforms
      @private
      */
      this.uniforms = uniforms || {};
  
      this.fragmentSrc = fragmentSrc || [];
  }