Procedural Plot

[jasonpickering]

Hey guys. I am thinking about ways to create a Procedural Plot for use in an upcoming game. I want the plot to be something similar to what you see in small JRPGs ,Zeldas, and Original D&D Modules.

"an Evil has arisen you must get a mcguffin to help you defeat it."

Has anyone done anything similar? The basic idea I have is:

1. Generate Main Character ( Class, Look, Starting Place)
2. Generate an Evil Monster ( Monster and Area of location)
3. Generate a Mcguffin (Based off evil monster and main character)
     Ex. If the Monster is the Evil Yeti and the Character is a barbarian then the Mcguffin is the Flame Sword
4. Build a world with 3 areas. (Starting area, Boss Area, Mcguffin Area)

So think it could work? this is obviously pretty basic and will require some extra stuff to make it seem actually interesting.

[Darren Grey]

Definitely double in the terms you describe, but I would worry that the MacGuffin generation would just come down to hardcoding lots of outcomes. It would thus just be random instead of procedural.

[Omnomnom]

To avoid the hardcoding lots of outcomes pitfall that Darren points out you could write an algorithm that iterates through all weapons in the game and select the one that does the most damage to the chosen boss when held by the chosen character.

If you are okay with a simple plot that should work fine, but if you want somewhat complex and yet serious plots then it'll probably be much harder. Check out this plot generator for example:
http://springhole.net/writing_roleplaying_randomators/creepypastaplot.htm

Produces a lot of absurd plots for every good one. You could generate 100 and your brain can easily find the best one, but how does a computer do that? seems to be a difficult problem. Maybe some kind of neural net could be trained to spot the bad ones, or good ones, but I've never done anything like that so wouldn't know.

[guest509]

  I've thought a bit on this.

HERO RL
-Genre is random. (Fantasy, Low Fantasy, Sci Fi, Western, Pulp, Super, etc...random, not procedural).

-Character and his stats are random according to genre (Wizard, Barbarian, Jedi, Gunslinger, Archaeologist, Brick, etc...use archetypes with many wild cards, so partially procedural.)

-Villian you fight is random, according to genre (created much like characters/heroes.)

-The villian's lair (the dungeon) is produced based on these factors
  -architecture (cave, dungeon, tower, castle, etc...) - procedural within these guidelines.
  -environment (swampy, lava, space station, etc...) - random, controls tileset, flora, fauna/beasts, terrain, traps, etc...
  -minions (mooks that work for the main bad guy, the boss of the lair. They will be produced like the Character and Villian are produced, only weaker.)

  Each 'mission' would be, say, 5 single screen levels. Fight the villian on the 5th level. You could produce an infinite number of missions. The game would really never end. Especially if you start letting your character jump genres. Think Cyborg fights Romans. You could upgrade your character between missions with the bonus earned by killing a villian (kill villian, gain level).

  Perhaps at some point you can kill the Arch-villian. Perhaps you can always attempt the Arch Villian mission, but you are afraid to try until you've killed enough lower level villians and gained enough power.


  That was a huge tangent. Sorry. I love these 'idea' threads.

@Darren - random vs. procedural? Is the 'lego' method of level creation random and the drunk walk or linked room method procedural? Is the distinction worthy of note as long as you include sufficient variety? Was Binding of Isaac procedural or random (probably random). Did it matter as far as replayability and ease of programming (not needing to create each level).

[guest509]

@NonNomNom - Not sure the quality of plot is that relevant. Games generally aren't great stories, it's the connection to your character's role in the action that keeps you engages. But I could be wrong.

[Darren Grey]

@Darren - random vs. procedural? Is the 'lego' method of level creation random and the drunk walk or linked room method procedural? Is the distinction worthy of note as long as you include sufficient variety? Was Binding of Isaac procedural or random (probably random). Did it matter as far as replayability and ease of programming (not needing to create each level).

Random can still be good, but in this area the distinction is that random involves a lot more hand-designed stuff from the developer.  In particular you need a huge base of content to draw from to stop "random" from being repetitive.

[Untrustedlife]

Im already developing a Roguelike in which procedural plot is important, it generates goals, names, situations (wars between races) and antagonists and the depth of the dungeon ( with different difficulties based on this) with a  formula   and the generator type is also randomized.  
and i will have a playable version out a couple months and I already have people playing it as testers. so ..yea

The game also chooses different generators (in this case: Catacombs, Dungeon (classic) and Stronghold (castle)
It generates Unique things about the dungeon (Haunted etc.) which effect the things you encounter

it generates different goals
The item you get will go with the theme, (haunted etc.)
(but the item is procedurally generated based on the dungeons stats)

it also can ditch item retrieval  and make you have to kill a boss for the goal instead)
a Liche (for haunted in this case)


It can do both as well (you may  have to kill the liche and get the haunted orb)

I would say start with basic plot gen first (the item and the dungeon stats) then add the bosses (possibly procedural also?)

[wire_hall_medic]

I love the idea, but don't quite agree with how you roughed it out.  I think that in JRPGs and Zelda games, the McGuffin isn't so much a weapon as a key, allowing you passage.

However, they don't tend to be particularly interesting in their role as a key.  It's their secondary uses that make them memorable.  Often (in Zelda games in particular), items grant a new form of movement/exploration.  For example, in Zelda 3, the following items are all necessary for progression; hookshot, bombs, fire rod, Ether Medallion, Quake Medallion, lantern, hammer, flute, shovel, book, mirror, Cane of Somaria, Master Sword, mirror shield, pegasus boots, two gloves, flippers, and the moon pearl.  Of those 19 items, all but 3 (the moon pearl, the flippers, and the book) are useful for more than the obstacles they allow you to pass.

These types of items have to be carefully scripted of course.  What I'd do, is add qualities to already useful items to make them quest items.  For example:

The Chime of Opening unseals the portal, but also has a random once-per-dungeon buff.
The guards won't let you pass until you get the amulet, which is a regularly generated magic amulet with the GUARD_PASS property added.
The ghost is only vulnerable to the weapon that killed them in life; a regularly generated weapon with the MURDER_WEAPON property added.

Also, OmNomNom's "find the best" idea is very good, assuming your generator is set up to handle it.  If not, you might just generate an item with little randomness (the class of weapon the PC is most proficient in, deals damage the enemy is weak against, of an appropriate strength for the difficulty).

[jasonpickering]

wow gone for a few days and I get a ton of answers.

so as for the item being just a key. My idea was similar to wire_hall_medic. I wanted the Flame Sword for example to give the player a Fireball spell. This would help with the boss who is weak to fire. If I did this it was going to be limited. the player would get few stats and one or two spells. I was thinking the game would be a quick play so the smaller stats seemed to work.

I also think that Jo and Darren were right. Procedural stories are hard to make good. so I guess what I want is procedural "Whatever it is that helps the player write their own stories". Like this villain having these minions. and then peppering in ideas from there. instead of writing specific dialog.

[st33d]

That usually comes from having lots of different interactions between elements.

Otherwise, so long as you expand your levels as a tree you should be able to put on a new branch that is relavent to the player's inventory and history. A story will appear to have occurred because of these "coincidences".

[guest509]

  Yes it's much easier, and fun, to create procedural goals that the player can pursue. The player sort of writes their own story.

  Interactive fiction can have tons of branches, but I've not seen actual narrative done well via procedural methods.

  But that's what you are really talking about anyway, when you say plot you mean End Goal, dungeon theme, etc...I mention the game FATE a lot. It's not that great of a game, it's an action RPG (diablo clone) but the boss at the bottom of the dungeon is a normal game creature, but buffed up. Like a zombie with way better stats, random abilities and loot. And bigger! The dungeon you traverse is procedurally generated but it's all the same crap you just hack through, and the dungeon isn't altered by who the boss is.