title: Controlling orientation of pie charts in R igraph
body: <p>I am plotting a network of nodes in igraph where some of the nodes are pies while others are solids. When I specify a node with two parts, I always get a node vertically divided into two. Is there a way to control the orientation of this line of division? For example, in the example node shown below (cropped form my bigger plot), can I make the division line go east-west or northwest-southeast (ideally any degree of rotation) instead of north-south? There is a pie.angle variable in the API but it didn't help when I played around with it. Any pointers would be much appreciated.</p>
  
  <p>Update: I am specifically looking for a solution within igraph, i.e., how to change orientation of the dividing line when one of the nodes in my igraph plot is defined to be of type "pie".</p>
  
  <p><a href="https://i.stack.imgur.com/cD3T3.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/cD3T3.png" alt="An example of the kind of nodes I am able to produce"></a></p>