Image resultImage = new Image(Display.getCurrent(), descriptors.size()*16, 16);
ImageData data = resultImage.getImageData();
data.alpha = 0;
resultImage = new Image(Display.getCurrent(), data);
final GC gc = new GC(resultImage);
int x = 0;
for (ImageDescriptor descriptor : descriptors) {
	if(descriptor != null){
		Image image = descriptor.createImage(Display.getCurrent());
		gc.drawImage(image, x, 0);
		x += image.getBounds().width;
	}
}
gc.dispose();
imageDescriptor = ImageDescriptor.createFromImage(resultImage);