# File lib/edi4r/diagrams.rb, line 404
    def initialize( diag )
      @diag = diag # Really needed later?
      
      # Init. to first segment of top branch, e.g. "UNH" or "EDI_DC40"
      @coord = NodeCoords.new(diag.branch, 0, 0)
      @coord_stack = []
      @down_flag = false
    end