Vertical grouping of BPMN activities

How one can make a vertical grouping of lanes ( Request & Approval) like the one shown in following example in exising BPMN editor ?


The Request & Response nodes and dragging possibility of same in exising BPMN editor code.

Perhaps you could organize the whole diagram into a table with a group in each cell?

That sample shows groups in columns as the overall orientation, but you could put them in rows instead.