code: function(filter) {
          if (!this.isActive())
              throw "Trying to set filter of texture that isn't active";
          var gl = this.gl;
          gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, filter);
          gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, filter);
      }
docs: Sets the min/mag filters