private Icon getIcon(TableModel model, int columnModelIndex) {
		Icon icon = null;
		if (model instanceof SortedTableModel) {
			icon = getSortIcon(icon, columnModelIndex, model);
		}
		if (isColumnFiltered(model, columnModelIndex)) {
			icon = combineIcons(FILTER_ICON, icon);
		}

		if (icon != null) {
			return icon;
		}
		return EMPTY_ICON;
	}
Paints a background highlight under the icon that will get painted.
@param g2d the graphics
@param scale the current scale, up to max 
@param max the max emphasis size
@param ix the icon x
@param iy the icon y
@param iw the icon width
@param ih the icon height
Ghidra/Framework/Docking/src/main/java/docking/widgets/table/GTableHeaderRenderer.java