Comment 4 for bug 536542

I think that I will leave the event types conquer_area and unhide_area unchanged because they can also be used in initializations (and compatibility with old savegames of scenarios).

Instead I will add the new event types conquer_region and reveal_region. All scenarios should use them instead of conquer_area and unhide_area.

The event type move_view does not really have to be changed. All that is needed is to allow giving a region name instead of a coordinate pair. But the region name is converted to a coordinate pair that is then stored in the event. (When writing, we could search for a region with the ID-point at the stored coordinates and write that name instead of the coordinates.)

All the trigger types (building, military_influence, ownership and vision) should be changed to only operate on regions (not point and radius). This breaks savegames, but only for the scenarios. People should just finish playing their tutorials with their current version. If they really want to keep a savegame, it can be fixed manually.