The Kendo-UI Diagram widget supports moving the whole diagram using the pan() method. However, the given offset does always have to be absolute.
Consider the following example:
The diagram is zoomed in and therefore not fully visible - assume a current offset of (-100, -100). The users should be able to pan using keyboard shortcuts. Whenever pressing one of the arrow keys, the diagram is moved in the corresponding direction by e.g. 50px:
If the user presses [ArrowRight], pan() needs to be called with an offset of (-50, -100).
If the user presses [ArrowUp], pan() needs to be called with an offset of (-100, -150).
However, since I do not know how much the diagram has already been moved, I cannot set the absolute offset required.
I have seen that pan() returns the current offset when being called without arguments, but this is not documented. Is this safe to use for that purpose or is there a better alternative? If yes, the documentation should be updated.