Hi there! Here's hoping I'm not too late on the scene and someone's still around to share experiences!
I'm looking into pcg for modular board games, like the DOOM board game from fantasyflightgames. The novelty here is the limited amount of board pieces available, as opposed to the virtually infinite space of online games. Is anyone aware of similar work in this area, as I have been unable to find such work.
Cheers
Jon
You're probably better off trying the PCG google group, rather than this discussion page.
I would like to know more about procedural icosaspheres. essentially it is a subdivided icosahedron, where every panel is a triangle so that texture mapping, or height mapping has no distortion anywhere on the polar coordinates. I know a little bit about what it is, but I have no idea how to do it.
The links mentioned in the Tigsource thread about PCG do not exist anymore.
"Braving Procedural Generation thread on TIGsource."
I propose the following:
Minh
We should make a section for books on procedural generation.
There are already a few good books out there, but the number is bound to increase as the subject gains more attention.
Since books count as an external resource, it should probably go on this page.
Then it would be instructive to change the name of the page to "Resources" from "External Links"
I was meaning by a) that if you down one set of stairs, then back up a second set, you will reach the first level you left. With b) this is not necessarily the case. In b) if you take the stairs you originally descended from, you return to the original level. But if you take another set of stairs up elsewhere, you could arrive on a new level. The geometry in b) is non-Euclidean.
And feel free to rewrite this to make it clearer. You can certainly have a graph in b), the naive implementation is a tree.
The paragraph about persistent levels currently reads:
With persistent levels, either a) the each 'floor' of the game is always the same once generated and all exits from the current level lead to one of two adjacent levels, or b) each exit from a level leads to a new level, which results in the game space consisting of a tree of levels branching away from the root which the player first entered where the number of children of the level equals the number of exits from that level, minus the one that the player arrived from.
Why is it only the case in a) that "each 'floor' of the game is always the same once generated". I would think this by definition is always true for persistent levels.
In b) I'm confused if it's meant that in the tree of levels, the player can go up to the 'parent' of the current level (i.e. the level where he came from) or not. If he can't, and a given level is only ever entered once, I'd say it's a case of non-persistent levels - unless they're the same the next time the game is played from scratch. If he can, then surely the parent levels should be the same as before in order for this to qualify as persistent levels?
Also, I would like to rewrite the paragraph to say that levels can be connected by arbitrary graphs rather than saying they must be connected either in sequence or in a tree structure, which is an arbitrary limitation of the definition in my opinion.
The wiki is not dead at all - I suspect it's that the regular contributors have been quite busy (I'm in the middle of working through an Unangband release, for instance). Feel free to contribute - I'm quite happy to proof read anything you've written.
Hello!
I am Piotr, student of University of Lodz in Poland. I love the idea of procedurally generating content of games and I dedicated a lot of my time to doing research in such algorithms. The best game so far I found was Dwarf Fortress by Tarn Adams, that generate everything on-the-fly, ranging form map (including rain shadows, climates, river erosion) and ending with detailed history of every creature (elf, human, dwarf, or dragon), civilization, deities and world locations (like caves). Amazing!
I hope the Wiki is not dead and I'm eager to publish some of my researches results in forms of articles, source codes, etc. As I generally can't speak English well (all my papers were written in Polish), I hope that someone here would be so nice and correct any flaws. Just to give you a nice snapshot of what my algorithms can do, let's play with my random logic riddles generator written in javascript: http://dl.dropbox.com/u/82366/Logic.html
Hi,
Drop me a line or reply to this post if you want access to the Google Analytics information for pcg.wikidot.com. Unfortunately, the permissions model for Analytics as I understand it means I can only give View Only access without having to throw away all the historical information and starting again.
Regards,
Andrew Doull
There are some notes at http://forums.tigsource.com/index.php?topic=5174.msg272093#msg272093 if you want to see what was talked about.
Thanks for the responses on this. I'm still not convinced either way, and have had people argue for both sides of the equation. I suspect the best approach to take is to be inclusive, but highlight the fact some people may not consider adaptive difficulty to be classically procedural.
Hi all,
Julian Togelius has set up a Google group for PCG at http://groups.google.com/group/proceduralcontent which appears to already have more discussion other than housekeeping than the forums here. I'd like to invite regular contributors to join the group - I suspect we should perhaps have a brief poll here on whether we should close down the forums here other than the General Discussion forum.
Regards,
Andrew
Its a tough call on this. Many popular games do some form of adaptive difficulty in ad-hoc and very game-specific ways. Makiyivka above makes a great point: the goal of procedural content is to open the gamespace, whereas often the goal of adaptive AI is to close it (but not always, consider something like the adaptive AI characters in Facade?).
I'd surely consider AI content though, the difficulty and complexity of which certainly affects the enjoyability of the game. I'd say only include games that feature adaptive AI as a major feature, like Left4Dead.
On the topic of Left 4 Dead, could you point me to a description of its adaptive difficulty, if you happen to have one? Because my limited experience with the game seems to suggest that what the AI Director is more an example of Algorithmic Difficulty, rather than adaptive….if I try to play a campaign on a difficulty that is too high for me, I will just fail the campaign. Likewise if I play on a difficulty that is too easy, I will run through it unchallenged. The AI Director may place the zombies in new locations each time, or order in zombie waves in different locations, but if I opt to play a hard campaign, then the AI Director will algorithmically give me a hard campaign.
A lot of the press about Left4Dead mentioned it's adaptive difficulty - [http://www.edge-online.com/blogs/gabe-newell-writes-edge] is probably the easiest example to find. I'll add it to the article.
The following is mostly a mixture of typing as I think and thinking at 3am, so hopefully it comes out coherent and useful.
From the 'What PCG is' page, you have created this as your base definition of PCG:
"Procedural content generation (PCG) is the programmatic generation of game content using a random or pseudo-random process that results in an unpredictable range of possible game play spaces."
A potential problem with adaptive difficulty as a PCG technique is that rather than allowing the player to explore an 'unpredictable range of possible game play spaces,' the goal of adaptive difficulty (as I understand it) is to constrain the player into the game designer's preferred play space. That is, if you are too good at the game, the game will get harder, so that you progress as expected. The same is true of the 'too bad at the game' case.
Take Resident Evil 4, for instance. Much of the tension, the overall 'experience,' in the game comes from managing a small amount of resources, primarily ammunition. Therefore, if I, as the game designer, want to ensure that a certain scene or boss 'feels' right, I need to make sure that the player has a given amount of ammunition when entering the fight, so that they get the experience I designed for them. By adding adaptive difficulty, I introduce a nice negative-feedback loop which prevents players from straying too far from this 'optimal' play space, by either removing excess resources if the player is too good (and thus has an abundance of ammo) or by adding in resources if the player is too bad (and is running the risk of leaving the game out of frustration).
Next look at Oblivion. The adaptive difficulty in this game, as far as I understand it, scales the monsters' levels with that of the player. So if I approach a tower at level 1, I will fight a level appropriate enemy. Similarly, if I approach that same tower twenty levels later, the enemies will have leveled up appropriately (perhaps the bandits have full plate mail and magical swords instead of cheap daggers and torn clothing). Now, again, this adaptive difficulty serves to focus the game into a very comfortable and safe player space…I will always be able to vanquish my enemies, provided I put in approximately the same amount of effort as I did previously. This adaptive difficulty removes the player's ability to explore the more 'dangerous' parts of the play space in favour of keeping the game friendly and playable. Now, this may have benefits for many players (I personally disliked the leveling world), but as far as resulting in the exploration of an "unpredictable range of possible game play spaces,' Adaptive Difficulty, as I have seen it implemented, seems to be designed to do the exact opposite: to allow the designer to better control the player experience.
On the topic of Left 4 Dead, could you point me to a description of its adaptive difficulty, if you happen to have one? Because my limited experience with the game seems to suggest that what the AI Director is more an example of Algorithmic Difficulty, rather than adaptive….if I try to play a campaign on a difficulty that is too high for me, I will just fail the campaign. Likewise if I play on a difficulty that is too easy, I will run through it unchallenged. The AI Director may place the zombies in new locations each time, or order in zombie waves in different locations, but if I opt to play a hard campaign, then the AI Director will algorithmically give me a hard campaign.
Anyway, I hope I've at least provided a decent springboard off of which to continue thinking about the issue of adaptive difficulty as it relates to this wiki.
While updating the PCG wiki today, I've come across the difficult notion of canon in procedural content generated games. I've flirted with this concept before, by defining games which are prototypically procedural, but in general I've tried to be inclusive rather than exclusive when it comes to including games in the PCG wiki.
I've hit a stumbling point writing up an article on adaptive difficulty - always a controversial point in games. I'll quote the whole article to saving you having to go to the original link:
Adaptive difficulty is the process of adjusting the game in reaction to the player. By spawning new enemies or powering up existing enemies if the player is progressing quickly through the game, or by decreasing the frequency and/or difficulty of existing enemies if the player appears to be having problems progressing, adaptive difficulty techniques attempt to create the 'optimal' game experience.
Classically, adaptive difficulty has been seen as a hard problem, requiring a level of artificial intelligence in the game to attempt to model the player to attempt to determine if they are finding the game easy or difficult.
However simpler RPG style mechanisms can also be seen as adaptive difficulty techniques. Allowing the player to level up by playing through additional easier content can ensure the player is able to grind their way through parts of the game in order to decrease the difficulty of sections of the game where the difficulty level increases. Paradoxically, adaptive difficulty techniques which increase the difficulty of the game by scaling up enemy strength have been fiercely resisted by RPG players, as can be seen by the negative reactions to the difficulty scaling in Oblivion.
Adaptive difficulty is not usually seen as a procedural content generation technique, but it has most of the features of such techniques. It could be seen as decreasing a game's randomness instead of increasing it which would make games which feature it without other PCG features to fall outside the 'canon' of PCG games.
Should I include games which have adaptive difficulty in the PCG wiki? There are plenty of examples of games which have adaptive difficulty and are procedural (Oblivion I've already mentioned, Left4Dead) but there are plenty of games which are not (SiN: Episodes). And I don't want to include every RPG, based on the argument I've made above.
The real question is not whether I should include these games, and the answer to that is probably not, but why? What good reason can I give to not include SiN: Episodes, for instance, as a procedural game?
Again, the randomness argument is the most plausible, but it is not completely convincing.
Convince me.
Is anyone able to get a write up of some of the events at the Procedural Content Generation symposium as outlined by Gillian? http://eis-blog.ucsc.edu/2009/10/eis-hosts-the-procedural-content-generation-symposium/
I'd love to be there…
'ownership' might be more accurately 'identification'.
It really happens though. In X-Com a soldier had the same name as a friend I knew, so he was kept around, even after I discovered PSI and found that he had mediocre PSI strength.
