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by cirno 2040 days ago
This only matters for things like encryption and secrets. Imagine if you published your game online as multi-player, someone could devise the randomness and predict the next moves in the game, which could allow them to cheat. For encryption, a predictable RNG can break the entire scheme.

In your casual sense of just a single-player game, there's no harm, but the idea in replacing MT with something like PCG is to be more secure/safe by default, since you never know what someone will use rand() for.
2 comments
ReactiveJelly 2040 days ago
https://www.datamation.com/entdev/article.php/616221/How-We-...

> recall that the seed for a 32-bit random number generator must be a 32-bit number, meaning that there are just over 4 billion possible seeds. Since the deck is reinitialized and the generator re-seeded before each shuffle, only 4 billion possible shuffles can result from this algorithm. Four billion possible shuffles is alarmingly less than 52!.

> To make matters worse, the algorithm of Figure 1 chooses the seed for the random number generator using the Pascal function Randomize(). This particular Randomize() function chooses a seed based on the number of milliseconds since midnight. There are a mere 86,400,000 milliseconds in a day. Since this number was being used as the seed for the random number generator, the number of possible decks now reduces to 86,400,000. Eight-six million is alarmingly less than four billion. But that's not all. It gets worse.

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joelwilliamson 2040 days ago
That article was rife with errors. Notably "recall that the seed for a 32-bit random number generator must be a 32-bit number" is quite obviously wrong, the seed size is constrained by the generator's state size, not its output size.
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hansvm 2040 days ago
Not just that, but their game is mildly more resource hungry than it could be because of the large MT state space, and depending on the exact nature of how many rolls/cards are expected per game and what is done with them MT could yield "unnatural" games at a highly elevated frequency which might play significantly differently from a physical counterpart.

I mostly agree though, the downsides are minor and/or rare if you aren't defending against attacks to the PRNG.

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