protected static Icon createIcon(Icon baseIcon, boolean isCallReference) {

		MultiIcon multiIcon = new MultiIcon(baseIcon, false, 32, 16);
		//@formatter:off
		TranslateIcon translateIcon = isCallReference ? 
				new TranslateIcon(FUNCTION_ICON, 16, 0) :
				new TranslateIcon(REFERENCE_ICON, 16, 0);
		//@formatter:on
		multiIcon.addIcon(translateIcon);
		return multiIcon;
	}
Indicates whether the associated reference is a call reference *
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/calltree/CallNode.java