This is a repost of an update to the v6.50 changes thread - relevant to the discussion here
There has been some debate on the forums about NPR interrupts so I thought it was worth clarifying how they work and what has changed for v6.50
There are two ways in which a turn can be shortened. If the program believes something is about to happen, like a missile or ship entering detection range, it will shorten the turn at the start. The second is through an interrupt, which is caused by a notable event and ends the turn so that the player (or an NPR) can react to it. Some interrupts are player only, such a ship being constructed or a system being surveyed, and some are interrupts for both players and NPR, such as a ship being destroyed or missiles being launched.
Note that the NPR AI code for movement and combat takes place at the start of a turn, so if anything significant happens relating to an NPR, the NPR needs a new turn in order to evaluate the event and react to it. Once a player interrupt occurs, it ends automated turns so the player can react. However, the AI doesn't need a break to react - it just needs to start a new turn - so interrupts are flagged as Player Events or Non-Player Events. A Player event is either something directly affecting a player, or an NPR event that involves a player, such as the NPR detecting the player. For NPR events that do not involve players, Automated Turns are not switched off. This is how it works in 6.40 btw - not a change for v6.50.
It's also worth noting that Automatic Turns only work if you are using the Tactical Map - the time buttons on the Population Window or the Galactic Map don't use Automated Turns.
In v6.40 there are 264 different events in Aurora, 60 of which don't cause interrupts for players and 184 of which don't cause interrupts for NPRs. For v6.50 I revisited the event list to see if I can reduce the number of interrupts for NPRs and now there are only 27 events that will trigger NPRs interrupts. The list is shown below. These are all events that the AI will need to evaluate and potentially issue a change in orders.
In addition for v6.50, I am going to change Player Events to only events that directly involve the player, so an NPR detecting a player will no longer stop automated turns.
NPR Interrupt Events
Target Hit
Missile Launch
Ship Destroyed
Damage Taken
Ship Slowed
Alien Fleet
Alien Population
New Thermal Contact
Population Surrender
Hostile Transit Detected
Jump Point Detected
New Alien Race
Missile Intercepted
New Hostile Contact
Missile Contact
Shipyard Contact
New System Discovered
Active Sensor Detected
Population Detected
Shields Detected
Jump Point Found
Ramming Attempt