/** Creates the images composing the grid when the color model is <code>GreyScale</code>. */
  private void createGridImagesForGreyScale() {
    int maxC = parent.getMaxC();
    List l = parent.getActiveChannelsInGrid();
    int n = l.size();
    clearList(gridImages);
    if (combinedImage != null) combinedImage.flush();
    switch (n) {
      case 0:
        for (int i = 0; i < maxC; i++) gridImages.add(null);
        combinedImage = null;
        break;
      case 1:
      case 2:
      case 3:
        if (isImageMappedRGB(l)) {
          BufferedImage image = parent.getCombinedGridImage();
          if (image == null) {
            for (int i = 0; i < maxC; i++) gridImages.add(null);
            break;
          }
          combinedImage = Factory.magnifyImage(gridRatio, image);

          int w = combinedImage.getWidth();
          int h = combinedImage.getHeight();

          DataBuffer buf = combinedImage.getRaster().getDataBuffer();
          List<ChannelData> list = parent.getSortedChannelData();
          Iterator<ChannelData> i = list.iterator();
          int index;
          while (i.hasNext()) {
            index = i.next().getIndex();
            if (l.contains(index)) {
              if (parent.isChannelRed(index)) {
                gridImages.add(
                    Factory.createBandImage(
                        buf, w, h, Factory.RED_MASK, Factory.RED_MASK, Factory.RED_MASK));
              } else if (parent.isChannelGreen(index)) {
                gridImages.add(
                    Factory.createBandImage(
                        buf, w, h, Factory.GREEN_MASK, Factory.GREEN_MASK, Factory.GREEN_MASK));
              } else if (parent.isChannelBlue(index)) {
                gridImages.add(
                    Factory.createBandImage(
                        buf, w, h, Factory.BLUE_MASK, Factory.BLUE_MASK, Factory.BLUE_MASK));
              }
            } else {
              gridImages.add(null);
            }
          }
        } else {
          retrieveGridImagesForGreyScale(l);
        }
        break;

      default:
        retrieveGridImagesForGreyScale(l);
    }
  }
 /** Creates the images composing the grid. */
 private void createGridImages() {
   // if (combinedImage == null) return;
   if (originalGridImages == null) originalGridImages = new ArrayList<BufferedImage>();
   clearList(gridImages);
   if (ImViewer.GREY_SCALE_MODEL.equals(parent.getColorModel())) {
     createGridImagesForGreyScale();
     return;
   }
   List l = parent.getActiveChannels();
   int maxC = parent.getMaxC();
   switch (l.size()) {
     case 0:
       for (int i = 0; i < maxC; i++) gridImages.add(null);
       break;
     case 1:
     case 2:
     case 3:
       if (isImageMappedRGB(l) && !parent.isCompressed()) {
         combinedImage = null;
         combinedImage = Factory.magnifyImage(gridRatio, renderedImage);
         int w = combinedImage.getWidth();
         int h = combinedImage.getHeight();
         DataBuffer buf = combinedImage.getRaster().getDataBuffer();
         List<ChannelData> list = parent.getSortedChannelData();
         Iterator<ChannelData> i = list.iterator();
         int index;
         while (i.hasNext()) {
           index = i.next().getIndex();
           if (parent.isChannelActive(index)) {
             if (parent.isChannelRed(index)) {
               gridImages.add(
                   Factory.createBandImage(
                       buf, w, h, Factory.RED_MASK, Factory.BLANK_MASK, Factory.BLANK_MASK));
             } else if (parent.isChannelGreen(index)) {
               gridImages.add(
                   Factory.createBandImage(
                       buf, w, h, Factory.BLANK_MASK, Factory.GREEN_MASK, Factory.BLANK_MASK));
             } else if (parent.isChannelBlue(index)) {
               gridImages.add(
                   Factory.createBandImage(
                       buf, w, h, Factory.BLANK_MASK, Factory.BLANK_MASK, Factory.BLUE_MASK));
             }
           } else {
             gridImages.add(null);
           }
         }
       } else {
         retrieveGridImages();
       }
       break;
     default:
       retrieveGridImages();
   }
 }