public static byte getRefLevel(RefType rt) {
		if (rt == RefType.EXTERNAL_REF) {
			return (byte) SymbolUtilities.EXT_LEVEL;
		}
		if (rt.isCall()) {
			return (byte) SymbolUtilities.SUB_LEVEL;
		}
		if (rt.isData() || rt.isIndirect()) {
			return (byte) SymbolUtilities.DAT_LEVEL;
		}
		if (rt.isFlow()) {
			return (byte) SymbolUtilities.LAB_LEVEL;
		}
		return (byte) SymbolUtilities.UNK_LEVEL;
	}
Get the reference level for a given reference type

<p>
TODO: Why is this not a property of {@link RefType}, or a static method of
{@link SymbolUtilities}?

<p>
Note that this was copy-pasted from {@code BigRefListV0}, and there's an exact copy also in
{@code RefListV0}.

@param rt the reference type
@return the reference level
Ghidra/Debug/Framework-TraceModeling/src/main/java/ghidra/trace/database/program/AbstractDBTraceProgramViewReferenceManager.java