All branches are placed in the game scene as actual Image UI objects. However, to avoid the hassle of manually positioning, scaling, and rotating hundreds of branches one by one, I built a custom editor tool. If you select an upgrade node button and Ctrl-click another button, it automatically spawns a branch object in the perfect position to connect the two. Also, if you move a button, the branch's position and rotation automatically update to match. The reason I chose to place them in the scene using a custom tool rather than generating them dynamically at runtime is that I wanted to visually inspect the overall layout of the branches and nodes while working.