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• # Realistic NPCs

Game Design and Theory

Realistic NPCs (Active vs Reactive)

* Subject: (General) Realistic NPCs (Active vs Reactive)
* From: scythe@u.washington.edu (Dan Shiovitz)
* Date: 9 Sep 1995 19:15:50 GMT
* Newsgroups: rec.arts.int-fiction
* Organization: University of Washington, Seattle

(This was discussed a little, I believe, around the time _Christminster_ came out. It's an important topic, so I thought I'd bring it up again.) (There are some vague spoilers for _Christminster_ and Curses here, which provide decent examples for what I'm talking about.)

In whatever next game I put out, I intend to have a real NPC (since I didn't have any real ones in my last game). To bolster the illusion of reality in an NPC, there are a couple things you can do. One of the things I was thinking about doing was having the NPC actually be active, rather than reactive. Most NPCs in most games are purely reactive. They don't seem to have any lives of their own, they take no initiative, they have no curiousity about the world, they have no apparent goals that they work to achieve, and (in worst cases) they don't even seem to have a reason for being in the adventure. This doesn't do much for my suspension of disbelief.

For instance, in _Christminster_ Professor Wilderspin has a one-room living space. If you inspect the fireplace, you notice the griffins to either side, and notice that they're one-eyed. Asking Wilderspin about them gives the response that they're unusual, created by such-and-such a person. Looking up their creator in your college book shows that he was rumored to have created a number of secret passages, and so on, and so forth. Professor Wilderspin is a professor of archaeology. He's used to pyramid explorations, and what-not.

Further on, we're shown he's curious and fairly intelligent. Yet we're supposed to believe he's never even wondered about the griffins? We're expected to believe he's lived in this room for who knows how long, and never even accidentally pushed an eye? Furthermore, to make matters worse, when you take the initiative and push an eye, all he says is something to the effect of "Wow, that's neat." There's no feeling there, there's no move towards "Hmm, what happens if we push both eyes at once!" [The above should not be taken as a personal attack on _Christminster_, persay. I enjoyed the game immensely, but its somewhat-detailed NPCs only show how much farther we have to go.]

So, I was thinking about making the NPC in my game be a little more active, more willing to take action (and maybe tell the player what to do!). The obvious problem with that is how to keep the NPC from solving all the puzzles, then? I'm not really sure what to do about that. One thing to try, I guess, is to have some puzzles that are character-specific, and some more that require cooperation. I suppose the NPC could even be used as a hint system, having them solve certain puzzles if the player takes too long. Anyone got other thoughts on the topic?

My ideal NPC interaction would be something like this:

>LOOK
South end of Attic
[...]
Igor is here.
A robot mouse is on the floor.
There is a small hole in the western wall.

Igor says "go west" to the mouse.  The robot mouse zips westwards into the
hole.
>Z
[..]
Igor sighs.  "The mouse can't hear me from out here," he says.
>HOLE, WEST
You bend down to the hole and say "go west" into it.  "Hey, good idea," Igor
says.  He bends down and says "go north" into the hole.  You hear the whirring
of wheels.
>HOLE, NORTH
Igor glares at you.  "Hey!  I'm the one with the map of the maze, here."
He bends down to the hole and says "go north" into it.  You hear the whirring
of wheels.
>IGOR, GIVE ME MAP
"Fine," he grumbles, handing you the map.  "You can do all the fun stuff, see
if I care."  He stomps off to the north.
>HOLE, NORTH
You hear the whirring of wheels, and an excited beep from the hole.
[etc]


I'm not sure how much effort this would take to do, but I think it is doable today with the programming we have.

------------------------------------------------+--------------
The Grim Reaper ** scythe@u.washington.edu     |
Dan Shiovitz   **  shiov@cs.washington.edu    |     Aude
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~   |    Sapere
_Music of the Spheres_ : Coming Nov '95  |
------------------------------------------------+--------------


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// GETTING DISTANCE BETWEEN TWO POINTS IN 2D // RESULT IS USED IN A CONDITION ALONGSIDE A CLOCK int vector_dist(sfVector2i mouse, sfVector2f pos) { int dist = 0; int x = mouse.x - pos.x; int y = mouse.y - pos.y; dist = sqrt(x * x + y * y); return (dist); }
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• When it comes to video games, immersion is one of the more popular topics among game critics and players alike, and for good reason. When you ask people why Marvel’s Spider-Man is such a joy to play, it shouldn’t surprise you if at least one of them tells you that the game “makes you feel like Spider-Man.” In fact, the phrase “makes you feel like…” is so common that it has been parodied and even ridiculed, with popular YouTubers like VideoGameDunkey providing direct examples of the phrase being used repeatedly in video reviews.
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• Hey, i'm new to the game developing, i have this idea of a basic fighting game, looking for a platform or an application where i can create this. The idea of the game is simple, but i don't know where can i develop this game.
The game would be a 1vs1, 2vs2 or 3vs3. Every character will have its own HP stat, Movement Speed stat and Jump Speed stat, the game is based on turns, so if it is your turn you can move freely depending on your movement speed and jump speed, and you can also use 4 attacks per turn.
The game is based on squares, like playing chess, the range of the attacks is calculated by squares and the movement speed of the characters is calculated by squares which can be horizontal, vertical or diagonal depending on the character. For example this is an idea of what movement speed should be like, if player 1 has 5 speed points and player 2 has 6 speed points. Jump Speed works as an additional movement speed, but you can use specific attacks while jumping. If you want to face another direction you will lose 1 movement speed point.

Now with the movement speed explained, i will explain how attacks will work. Attacks are also based on squares, the range of the attack to be precise. Every character will have 5 types of attacks, which are, Charged Attacks, Special Attacks, Tilt Attacks, Aerial Attacks and Grab Attacks. Each attack will have its own range, damage, knockback and launch direction. If the opponent has 10 HP and your attack has 3 damage points, your opponent will lose 3 of its HP, and the game won't finish untill the opponent loses all of its HP.
Charged Attacks are the strongest attacks, usually they have an average or high knockback. Special Attacks have neutral damage, and can also include movement speed while using them. Tilt Attacks are weak attacks that usually have low knockback so you can combo on them if you are close to the opponent. Aerial Attacks have neutral damage, and can only be used while performing a jump. And finally Grab Attacks, drags your opponent in front o you and it will perform an attack, you can add extra damage to your Grab Attacks, but you will lose your attack turns.
This is the list of attacks available per category:
- Charged Attacks: Forward Charged Attack, Up Charged Attack, Down Charged Attack.
- Special Attacks: Forward Special Attack, Up Special Attack, Down Special Attack.
- Tilt Attacks: Forward Tilt Attack, Back Tilt Attack, Neutral Tilt Attack, Up Tilt Attack, Down Tilt Attack.
- Aerial Attacks: Forward Aerial Attack, Back Aerial Attack, Neutral Aerial Attack, Up Aerial Attack, Down Aerial Attack.
- Grab Attacks: Forward Grab Attack, Back Grab Attack, Up Grab Attack, Down Grab Attack.
Each of this attacks will be different on each character. If your opponent is behind you and you dont have any movement speed to change your position, you can perform a Back Attack, because the hitbox usually is behind you. Up Attacks usually launches the opponent vertically, if the Up Attack with vertical launch has low knockback, you can combo with other moves without moving, but if the Up Attack has high knockback, the opponent can perform an air dodge, to any direction, but vertical launching moves with high knockback can early K.O the opponent even if the opponent hasnt lost all of its HP.
There are different types of hit boxes, each of them works differently.
- Hit Box: Causes damage.
- Additional Hit Box: Causes additional damage. (Only certain attacks have additional hit boxes)
- Character Hit Box: Causes damage also in the player box.
-  Air Hit Box: Causes damage only when your opponent is in the air.
- Alternate Hit Box: Causes damage if you choose to. (Only certain attack can have alternative hit boxes, like blasting attacks)
- Trip Box: The squares your character is moving while performing an attack.
- Drag Trip Box: The same as Trip Box but it drags your opponent with you while you are using the attack.
- Alternate Trip Box: The squares your character will move if you choose to.
- Grab Box: The range of the grab, to perform a Grab Attacks, works almost like a Hit Box. (But will have a special animation)
This is the idea of how the hit box will work, of two different attacks. In which the Player 1 uses an attack with 2x6 squares hit box and Player 2 uses an attack with 1x4 squares hit box.

This is an example of Player 1 using a Charged Attack with 2x6 squares hitbox on Player 2 that has 5 knockback squares.

This is an example of Player 1 using an Special Attack on Player 2, that has a Trip Box and a 1x6 square hitbox that has 4 knockback squares.

This is an example of Player 1 using an Special Attack on Player 2, that has a Dragging Trip Box and a 1x6 square hitbox that has 4 knockback squares.

This is an example of Player 1 using an Up Tilt Attack on Player 2, that has a 1x1 hitbox with very low knockback, and causes a vertical launch to the opponent.

This is an example of Player 1 using an Up Tilt Attack on Player 2, that has a 1x1 hitbox with high knockback, and causes a vertical launch to the opponent. But the high knockback let the opponent to air dodge to the right. (Air dodge has 3 movement squares) (If Player 2 had less than the half of its HP it would instanlty K.O it)

This is an example of Player 1 using a Back Grab on Player 2, with a 1x2 Grab Box and 7 knockback squares.

This is an example of Final Fantasy Brave Exvius, that's similar of what i plan the game to look like.

But with a more cartoon look like this, it's just an idea. I accept suggestions.

Thanks for reading my post, that's the basic idea of the game, i tried to be very simple with the explanation, but if someone its interested on more details i can give them by message. Which platform i can use to develop this game, that works with squares, and damage, HP, attacks, etc.
• By RTNO1
Hi there,
Please help us evaluate three fighting-game streaming channels (Twitch) through the following SurveyMonkey page:
https://jp.surveymonkey.com/r/8PR7QRD
It takes around 15 to 20 minutes to finish this evaluation.
Thank you so much in advance for your contributions to fighting-game research. If possible, please finish the survey by this Sunday.
Team FightingICE
http://www.ice.ci.ritsumei.ac.jp/~ftgaic/
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