1. Premiere Pro (all versions)
2. macOS (tested all recent versions, bug probably applies to Windows too)
3. Start with sample plugin from the SDK that uses custom UI using AE SDK APIs. Attempt to use callbacks in PFAppSuite4 as explained below.
4. APIs in PFAppSuite4 should work just as they do in AE, instead they fail and sometimes seem to have nastier side effects on the host app.
Premiere Pro allows third-party plugins based on the AE SDK to obtain callbacks for PFAppSuite4. (as a side note, AE has been on PFAppSuite5 for a long time now)
Unfortunately many of these callbacks do not work at all. PF_ConvertLocalToGlobal() returns a 515 PF_Err and simply resets the given point to zero. The function should instead allow one to convert a local coordinate – local to custom UI appearing in the inspector – to screen coordinates.
Similarly, PF_AppGetColor() returns nonsensical values (for example, try calling with PF_App_Color_HOT_TEXT) and seems to have other negative side effects... i.e. after calling this function the UI in the inspector may not draw correctly, as if the call corrups the current Drawbot environment.
It would be nice to get this API to work in Premiere Pro. It is extremely important for plug-ins that display custom UI to know where on-screen the UI is being drawn. This is useful when displaying a popup menu, for example, since once can match the location and width of a popup menu to the frame of the control that displays it.
As it stands, in Premiere Pro one can only obtain the current mouse location through system-level APIs (think [NSEvent mouseLocation]) and would be unable to convert coordinates at all.