buildFilter method

@override void buildFilter()

Builds the mask filter and image filter for the blur effect.

This method is called when the filter is marked as dirty and needs to be updated.

Implementation

@override
void buildFilter() {
  var maxBlur = maskSigma;
  if (maxBlur == -1) {
    maxBlur = Math.max(_blurX, _blurY) / 2;
    if (maxBlur < 1) maxBlur = 1;
  }

  /// if it goes under a threshold (I tried .2 and lower), it flickers.
  /// idk which logic uses, but 1.0 seems like a stable min number for the
  /// mask.
  _maskFilter = ui.MaskFilter.blur(style, maxBlur);
  _imageFilter = ui.ImageFilter.blur(sigmaX: _blurX, sigmaY: _blurY);
}