I have implemented an interactive, one-to-many flow diagram.
The user should be able to build the structure of the flow diagram by adding child nodes to a parent node, as well as be able to change the parent node of child nodes by adding a new parent node.
Parent and child nodes are connected by a dotted line that is approximately 100 pixels in length/height.
I've designed an icon that is a 20 px by 20 px circle with a plus sign inside of it that users can click on to add a child node or add a new parent node. I can't determine what the best placement would be for the icon that users click on to add a new parent node and the icon that users click on to add a new child node.
Imagine a parent node that is a 100 x 80 pixel rectangle, with a 100 pixel dotted line that connects it to it's child node, which is the same dimensions as it's parent. The user wants to perform one of two actions: change the parent of the child by adding a new parent, which will effectively make the new parent a child of the old parent and make the new parent the parent of that child, or, add another child to the parent node. What are some ideas on where I could place the icons to perform both of these actions, that would be user friendly and intuitive? I'm also totally open to ditching the current icon that I am using and taking a totally different approach.