Adding visuals to code editor

I was researching an eclipse plugin when I saw the following screenshot whish got me thinking.




Is there any way I could use a similiar interface when editing code.
Ideas
Perhaps use this type of interface to

• edit the called method inside the same editor as the call.
  
• show the overridden method and overriding method in the same editor. I can see all sorts of possibilities here particularly for code which includes extensive use of the template pattern as much of the code I write seems to.
  
• a call hierarchy or inheritance hierarchy using expand ,colapse and focus on similliar to the hierarchy view but all inside the editor view.
  

Now I don't claim to have thought this through but that is how ideas start.