void checkNewGroup(int atomIndex, int modelIndex, char chainID, String group3, int groupSequenceNumber,
			char groupInsertionCode) {
		String group3i = (group3 == null ? null : group3.intern());
		if (modelIndex != currentModelIndex) {
			currentModel = mmset.getModel(modelIndex);
			currentModelIndex = modelIndex;
			currentChainID = '\uFFFF';
		}
		if (chainID != currentChainID) {
			currentChainID = chainID;
			currentChain = currentModel.getOrAllocateChain(chainID);
			currentGroupInsertionCode = '\uFFFF';
			currentGroupSequenceNumber = -1;
			currentGroup3 = "xxxx";
		}
		if (groupSequenceNumber != currentGroupSequenceNumber || groupInsertionCode != currentGroupInsertionCode
				|| group3i != currentGroup3) {
			currentGroupSequenceNumber = groupSequenceNumber;
			currentGroupInsertionCode = groupInsertionCode;
			currentGroup3 = group3i;
			startGroup(currentChain, group3, groupSequenceNumber, groupInsertionCode, atomIndex);
		}
	}