When you create a new game the random seed gets reset so you'll get entirely different items but they'll remain constant throughout the play-through.
Well, this is not really true
Changing the seed will change the RNG output (obviously), however using the same seed for two games still won't guarantee the same loot.
The seed is only used for initialization (so you'll get the same random number in the two games at the very beginning of the game), however each subsequent generation changes the internal state of the generator, so depending on the players actions the RNG states will be completely different in the two games, despite the same seed --> different loot.
Incidentally, this is the reason why saving the seed is not a reasonable approach to prevent save scumming. As many events (eg. NPC wander behavior) are tied to the RNG, simply waiting a few seconds more after reloading a savegame will change its state sufficiently enough to give you different loot.
You are assuming that RNGs are always seeded with the current time, this needn't be the case, if you re-initialize a RNG with the same seed the output will be the same. And since RNG's are generators, (as described in my previous post) then if you keep track of how many times you've already called it you can hop ahead to that "place" in the sequence.
In the example in my previous post I'd seed the generator once (possibly with the current time) when the game is created (so when you click "new game"), then the seed would be put in the savegame and every time after that when you load a game the saved seed would used.
@ BlackDragon.
Sure. But look at the work involved, the possibility for bugs and the fact that you take all that time to engineer a way to make the game worse. Waste, no?
Well, the amount of work would depend on how loot is generated, it could be fairly easy to implement, it merely sounds complicated.
Just wanted to note that I was merely interested in providing a technical solution (and proving that a viable system to avoid save scumming for loot could be reasonably implemented), I personally don't really have an opinion on whether they should or should not implement such a system.
