Heh. I am preemptively shutting down violence arguments regarding Radiant AI. Whenever Radiant AI is talked, people bring the reasons Beth gave for its lobotomy, like NPCs killing each other for smallest conflicts. Much like how you pick up a cabbage and everyone becomes a murderer lusting for your blood, NPCs also suffer from that without a quicksave option. It supposedly makes ghost towns down the line. I think, that is a super weak argument. Make NPCs behaviors less violent, less crimey. This has been like this since Morrowind.

A goal is something I define as the answer to the question "WHY?". So here the answer is because a game designer put a schedule on the NPC, "17:00, 18:00 EAT". Where I expect it to be "because I am hungry." on NPCs behalf. Internal clocks vs. game designer. One is meaningful internal logic, the other is external. One is autonomous, the other is "scripted".

Packages contain behaviors which are pretty autonomous and they are quite impressive. So I believe the abstraction should arrive one level later. Instead of, giving it a duration and a position and a target and a weapon by game designers, it should be a simple "NPC's goal is to practice bows until he gets mastery". That's more like it. The rest of the values should also be automatic. So the NPC can select places and time to practice himself too.

This shows there must be a division between unique personal goals like "mastering archery" and general goals like eating, sleeping...

Binding the autonomous systems to schedules makes the whole thing a streamlined "scripted events" template for designers' convenience. I believe Radiant AI systems are pretty advanced but also heavily underutilized. They should update the level of abstraction regarding Radiant AI, it has been almost 10 years since Oblivion. That's my criticism.

The packages are called AI packages because each is a little bundle of AI that tells an NPC how to perform a task.

https://www.youtube.com/watch?v=rT21r2dAqp8 guides it through the task of cleaning a floor. Nowhere in the Roomba's AI is there a block of code to make it to start cleaning floors because it hates dirt. "Why" is irrelevant. You specify the times it should begin its rounds, perhaps 11 AM every Tuesday and Friday. In no way does the Roomba's schedule warrant our calling its behavior scripted.

Much as the Roomba's AI allows it to carry out the task of cleaning, the Eat AI allows an NPC to carry out the task of eating. Take away the AI, and the NPC cannot perform his task. If in place of the AI, you were to provide a script for the task and have the NPC follow it, then you could rightly call his performance scripted.

For AI, "why" is everything. Because whys can interact with each other too. That's where emergent behaviors would occur. Otherwise, you see the same thing performed again and again, just like a scripted event.

PS. Examples:

you buy a meal to an NPC just before 6:00, then 6:00-7:00 eat schedule triggers and NPC still goes and eats like he is hungry. Scripted events alike.

You clear the place yourself, Roomba attempts to clear it again. Because Roomba has [censored] AI and that's what I AM saying. And I can't believe you compared that robot to Characters in an immersive RPG.

PPS. I see your Roomba and https://www.youtube.com/watch?v=D9RhgrwkTFQ.

Well, they've got a great tool with radiant AI for making some wild emergent gameplay, but they've still got to make a functioning game. I think they're less interested in creating NPCs with their own goals and motivations that make their own decisions, and more about having a system that lets them get every actor to do anything the designers need them to do to create believable scenarios.

You may enjoy http://www.gamasutra.com/view/news/251947/Video_Why_you_shouldnt_rely_on_emergent_behavior_in_your_game_AI.php on emergent behavior in game AI.

You bet. Nails on a chalkboard. "Emergent behaviors are nothing special, I can write more efficient versions of them myself." It is not only limiting but backwards too. You don't even know x, y, z emergent behaviors beforehand. After the fact, you will attempt to do it in a more efficient way and without even realizing, you will lose access to emergent y and z behaviors that would have been found later. That's the beauty of emergent behaviors, they can apply to more situations than you can plan. That's the whole point in fact.

I know games I enjoy the most, immersive sims featuring emergent gameplay where systems interact with each other creating something more than its sums. It is funny, they have the best and most fun AI too.

I'm not particularly good with computers and such, but to me what your saying is instead of wanting a preprogrammed schedule of events you basically want the AI to have like an internal clock (hunger metre) where when it gets to critical levels the AI would go get food, so not neccessarily always between say 7:00 and 8:00 is eat and 8:00 to 10:00 is archery practice. As for the archery practices example I have no idea how that would be handled outside of a schedule.

This is a pretty fascinating topic though. I remember watching the demo for Oblivion and being blown away, now I look back on that and I'm like this is not particularly exciting.

Of course, depending on their personal circumstances, many (or even most) real people either prefer or are obliged to follow a schedule of sorts. They prefer to have their meals at around the same, they are obliged to get to work by a certain time, they have to keep their shop open to a regular schedule...

This is one reason why it was a reasonable fallback position for Bethesda, when they found that emergent gameplay without proper limits tended to create chaos, to mostly limit NPCs to schedules, because that creates a superficial appearance of realistic behaviour that can be more convincing than an actual needs-driven AI.

Not that a better solution couldn't have been found, but at least the schedule-driven solution was straightforward and predictable (which is, of course, also its great weakness) and so could be QA'd in a sensible timescale with a reasonable number of staff.

I chose the Roomba because it exemplifies Bethesda's original, and current, purpose for Radiant AI.

Schedules are not a fallback position. All of the comedic and frustrating AI problems that Bethesda reported from their development of Oblivion happened with NPCs that followed schedules. Schedules were not the cause of any problems, nor were schedules a solution.

Radiant AI was made for task automation. What Bethesda had in mind for NPC AI is something akin to the AI for https://www.youtube.com/watch?v=rT21r2dAqp8. You order the robot to do something -- vacuum a floor, for instance -- and its AI, not you, guides the robot through the task. With Radiant AI, you order an NPC to sleep, and its AI walks it through any necessary steps for sleeping. Along with other kinds of triggers, schedules pass orders to NPCs, and AI allows the NPCs to carry out their orders.

The needs Todd mentions in https://www.youtube.com/watch?v=pjbx6-KQoRg are based on an NPC's current orders. When an NPC is ordered to practice archery, then the NPC needs a bow and arrows. When an NPC is ordered to sleep, then the NPC needs a bed. When an NPC is ordered to eat, then the NPC needs food. Through Radiant AI, an NPC figures out what it needs and how to get it.

Schedules probably are the better solution for producing natural-seeming NPC behavior. As you say, people tend to follow schedules, and people are social. People work when others are working, and eat when others are eating, and they often work and eat together. With schedules, It is easy for a designer to show players a semblance of the norm, and it is easy for the designer to show players deviations from norm.

Ah, a difference of interpretation. Of course AI packages in a stack each have different conditions that enable them, and those conditions can include a schedule.

However, I tend to think of a schedule as being a strictly regimented set of behaviours to a tightly defined... well, schedule... with only one behaviour (or AI package) in play at any one time. Whereas, of course, it would be possible to have a whole stack of AI packages where time of day was not part of their conditions, and they were constantly coming into and out of priority as the NPC's circumstances changed.

Limiting NPCs to the most simplistic arrangement and conditioning of their packages (by time of day) is what I meant when I referred to a schedule as a fallback position - Bethesda developed a hugely flexible system, found problems using it flexibly, and so for the most part resorted to using it in simplistic but predictable ways.

Still, I may have misunderstood some of the points people have been making and their understanding of how AI packages work - and my understanding of them is not all it could be

You were explaining... I misunderstood, I thought you were defending it.

I enjoyed watching that - thanks