An example of Randart generation "gone wrong"
Posted: Sun 09.05.2010, 12:38
Random artifacts have always been a much discussed topic in MAngband and much has been said about their advantages as well as their disadvantages. While I certainly don't know everything about how they work I think I know enough to see a lot of potential problems with implementing random artifacts in a multiplayer environment on servers that may be running continually for years, such as mangband.org.
One of our main worries has always been that due to this being a multiplayer game that has a static "world", as in, no frequent resets, the random artifacts would eventually "flood" the game. Of course mechanisms could be created to deal with this but it still seems like a sort of basic "flaw" with the concept being applied to a multiplayer server that runs for years.
The other main concern is that individual randarts can be unbalancing, too powerful and an example can be found in the pastelog below and the following discussion on the item in angband-dev.
This particular item is the randart equivalent to Bladeturner so it is naturally not a representative for your typical randart, but imagine on a server like mangband.org, with a large number of high level people, running for years and an item of this power theoretically (as far as I understand) being generated "every half-dozen game".
***
http://pastie.org/952243
I'll quote from the channel:
<sorear> is the randart generator supposed to ever make stuff with so many properties that it overruns the screen?
<magnate> sorear: there is no check on the number of properties on a randart. The problem you're seeing is #865
<Chessa> http://dev.rephial.org/trac/ticket/865
<sorear> magnate: I am aware of the issue; however, the randart generator giving me weapons superior to Grond is dubious
<magnate> hmmkay. Then the problem is not about the length of the description!
<magnate> With the right combination of mods it is possible that a powerful artifact like Bladeturner can become an overly powerful weapon. That's one reason people like randarts.
<magnate> It is not common - only once every half-dozen games does such a weapon occur, and of course it doesn't necessarily get generated in the game.
<magnate> IMO this is an acceptable problem. To solve it would be to compromise the rest of randart generation, AFAICT.
<sorear> "become"?
<sorear> http://pastie.org/952243 <- the object in question
<magnate> Nice. Not actually more raw damage than Grond, but the triple brand and all three x5 slays is pretty special with +5 speed. If it didn't aggravate it could be considered excessive.
<magnate> Do you have the randart.log from that game? It would be interesting to see which artifact spawned it - my guess is Bladeturner or Deathwreaker.
<magnate> It would also be good to check that it wasn't too easy to find - min depth >90 and alloc_prob 1 I would hope
<sorear> yes, I do
<sorear> how do I read this file?
<sorear> magnate: note that that is a 5 blow weapon, while grond is only 3
<sorear> and the pile of high resists would be something if I hadn't found the One *even earlier*
<sorear> /Moromur turns up nothing
<magnate> Ah well, The One is never randomised, so that isn't my fault!
<magnate> Sadly the log file does not store names, so you need to know its index number
<magnate> If you have the savefile still active, you can generate the spoiler
<magnate> That will tell us the min depth and alloc_prob
<magnate> The only way to find it in the log file without knowing the number is to find the combination of slays, so you're looking for /Anm Evl Orc Trl Gia XDr XUn XDm Acd Elc Cld
<magnate> (But sadly not necessarily in that order)
<magnate> (And yes I hadn't realised Grond was limited to 3 blows)
<magnate> It isn't the best Morgoth-killer I've ever seen, but certainly one of the best overall.
* sorear restore backup save
<sorear> ^a " 2
<sorear> Beautiful.
<magnate> ?
<sorear> artifact.spo
<sorear> is
<sorear> Moromur: Level 100, Rarity 255, 22.5 lbs, 500000 AU
<magnate> Ooh, you're playing with an old version then
<magnate> And yes that's Bladeturner - you were lucky to find it with rarity 255! What level did you find it on?
<magnate> So you're playing 3.1.1?
<magnate> Given the level and rarity, it doesn't seem overly broken
<sorear> it was index 17
<sorear> oh
<sorear> I started this game on 4/10 after a svn up
<sorear> does that count as "old"
<magnate> Yup, 17 is Bladeturner.
One of our main worries has always been that due to this being a multiplayer game that has a static "world", as in, no frequent resets, the random artifacts would eventually "flood" the game. Of course mechanisms could be created to deal with this but it still seems like a sort of basic "flaw" with the concept being applied to a multiplayer server that runs for years.
The other main concern is that individual randarts can be unbalancing, too powerful and an example can be found in the pastelog below and the following discussion on the item in angband-dev.
This particular item is the randart equivalent to Bladeturner so it is naturally not a representative for your typical randart, but imagine on a server like mangband.org, with a large number of high level people, running for years and an item of this power theoretically (as far as I understand) being generated "every half-dozen game".
***
http://pastie.org/952243
I'll quote from the channel:
<sorear> is the randart generator supposed to ever make stuff with so many properties that it overruns the screen?
<magnate> sorear: there is no check on the number of properties on a randart. The problem you're seeing is #865
<Chessa> http://dev.rephial.org/trac/ticket/865
<sorear> magnate: I am aware of the issue; however, the randart generator giving me weapons superior to Grond is dubious
<magnate> hmmkay. Then the problem is not about the length of the description!
<magnate> With the right combination of mods it is possible that a powerful artifact like Bladeturner can become an overly powerful weapon. That's one reason people like randarts.
<magnate> It is not common - only once every half-dozen games does such a weapon occur, and of course it doesn't necessarily get generated in the game.
<magnate> IMO this is an acceptable problem. To solve it would be to compromise the rest of randart generation, AFAICT.
<sorear> "become"?
<sorear> http://pastie.org/952243 <- the object in question
<magnate> Nice. Not actually more raw damage than Grond, but the triple brand and all three x5 slays is pretty special with +5 speed. If it didn't aggravate it could be considered excessive.
<magnate> Do you have the randart.log from that game? It would be interesting to see which artifact spawned it - my guess is Bladeturner or Deathwreaker.
<magnate> It would also be good to check that it wasn't too easy to find - min depth >90 and alloc_prob 1 I would hope
<sorear> yes, I do
<sorear> how do I read this file?
<sorear> magnate: note that that is a 5 blow weapon, while grond is only 3
<sorear> and the pile of high resists would be something if I hadn't found the One *even earlier*
<sorear> /Moromur turns up nothing
<magnate> Ah well, The One is never randomised, so that isn't my fault!
<magnate> Sadly the log file does not store names, so you need to know its index number
<magnate> If you have the savefile still active, you can generate the spoiler
<magnate> That will tell us the min depth and alloc_prob
<magnate> The only way to find it in the log file without knowing the number is to find the combination of slays, so you're looking for /Anm Evl Orc Trl Gia XDr XUn XDm Acd Elc Cld
<magnate> (But sadly not necessarily in that order)
<magnate> (And yes I hadn't realised Grond was limited to 3 blows)
<magnate> It isn't the best Morgoth-killer I've ever seen, but certainly one of the best overall.
* sorear restore backup save
<sorear> ^a " 2
<sorear> Beautiful.
<magnate> ?
<sorear> artifact.spo
<sorear> is
<sorear> Moromur: Level 100, Rarity 255, 22.5 lbs, 500000 AU
<magnate> Ooh, you're playing with an old version then
<magnate> And yes that's Bladeturner - you were lucky to find it with rarity 255! What level did you find it on?
<magnate> So you're playing 3.1.1?
<magnate> Given the level and rarity, it doesn't seem overly broken
<sorear> it was index 17
<sorear> oh
<sorear> I started this game on 4/10 after a svn up
<sorear> does that count as "old"
<magnate> Yup, 17 is Bladeturner.