Swing/RatingLabel のバックアップ(No.12)

private final ImageProducer ip = orgIcon.getImage().getSource();
private ImageIcon makeStarImageIcon(float[] filter) {
  SelectedImageFilter sif = new SelectedImageFilter(filter);
  return new ImageIcon(
    createImage(new FilteredImageSource(ip, sif)));
}
private class SelectedImageFilter extends RGBImageFilter {
  private final float[] filter;
  public SelectedImageFilter(float[] filter) {
    this.filter = filter;
    canFilterIndexColorModel = false;
  }
  @Override public int filterRGB(int x, int y, int argb) {
    int r = (int)(((argb >> 16) & 0xff) * filter[0]);
    int g = (int)(((argb >>  8) & 0xff) * filter[1]);
    int b = (int)(((argb      ) & 0xff) * filter[2]);
    return (argb & 0xff000000) | (r<<16) | (g<<8) | (b);
  }
}