I made such a form ( trade flows between 7 regions) where the nodes stand for the inner- regional flows (for example within Asia) and the connecting tubes for the intra- regional trade ( like between Europe and Asia ( two direction). Problem: The volumes have to correspond to the the $- values. This was complicated, had to do it fully manually/ iterative; found no plugin or program that could at least deliver some skd design. Here it is:
1 Like
Have a look at @TIG 's Scale to Volume.