srecord noeq G22RegionPanel(IImageRegion region) > MetaWithChangeListeners is Swingable {
  settable transient G22Utils g22utils;
  settable BufferedImage originalImage;
  settableWithVar bool showOriginalColors = true;
  transient ImageSurface is;

  cachedVisualize {
    is = g22utils.stdImageSurface();
    imageSurfaceCheckerBoardBackground(is);
    varShowOriginalColors().onChangeAndNow(l0 updateImage);
    
    ret northAndCenterWithMargins(
      jcenteredline(
        liveValueCheckBox(varShowOriginalColors(),
          "Show original colors"),
        jbutton("Save mask", rThread saveMask)
      ),
      g22utils.wrap(is));
  }
  
  void updateImage {
    if (showOriginalColors)
      is.setImage(new CutOutRegionFromImage(region)
        .margin(10).fullImage(originalImage)!);
    else
      is.setImage(regionToBinaryImage(region));
  }
  
  void saveMask {
    var maskSize = g22utils.projectInfo().defaultMaskSize();
    var maskImage = g22standardRegionToMaskImage(region, maskSize);
    new G22MaskConcept mask;
    mask.maskImage = maskImage;
    g22utils.registerConcept(mask);
  }
}

Began life as a copy of #1035971