A potential issue that I’ve just bumped into is that, when a DirectGUI item is selected by keyboard or gamepad, we presumably want this selection to be visible. One idea for this that occurred to me was to simply set the control into its “roll-over” state–it seems simple at first thought, and is consistent with the extant behaviour of DirectGUI.
However, it looks like DirectGUI is designed in such a way that this isn’t straightforward: attempting to set the state of a DirectButton or similar to “DGG.BUTTON_ROLLOVER_STATE” seems to have no effect. This conclusion is supported by this (admittedly old) thread. (Unless I was using the wrong state-value there?)
(For the purposes of the simple project that I mentioned above, I intend to just use an additional DirectLabel placed “behind” the controls, with a design on it, or something similar.)