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0 pointstfinniga11y ago0 comments

It depends on the pseudorandom number generator that you're using, but you'd be hard pressed to find a standard library prng where similar seeds produced similar random numbers. That would be pretty bad design.

For example, here is some code I wrote to test my own prng:

srand(1000000); for( int i = 0; i < 10; i++ ) printf( "%d\n", rand() );

printf("====\n");

srand(1000001); for( int i = 0; i < 10; i++ ) printf( "%d\n", rand() );

And here is the result:

21585 18586 29373 4301 3304 21158 23657 21142 2144 26110 ==== 21589 29335 14469 28364 13618 25085 26770 18215 18656 19962

As you can see, they diverge really quickly.

0 comments

chton11y ago

I'm aware of how prngs work, and of how often they are misused. What I was mostly wondering was how big an effect that would give in the final product. Do typical maze generation algorithms use it extensively, or sparingly so the differences are minor? How different would the maze look if the seed was different, and is it likely that you could get very similar mazes from completely different seeds?

tfinnigaOP11y ago

I think the short answer is that the maze will look very different. It's very possible that the verts of the maze would be in exactly the same position, since that's a regular pattern. But the maze walls will be extremely random.

Maybe the best way to get a feel for it is to take a look at this page of maze generators: http://weblog.jamisbuck.org/2011/2/7/maze-generation-algorit...

chton11y ago

That's a great page. I learned a lot, thanks!

j / k navigate · click thread line to collapse

0 pointstfinniga11y ago0 comments

For example, here is some code I wrote to test my own prng:

srand(1000000); for( int i = 0; i < 10; i++ ) printf( "%d\n", rand() );

printf("====\n");

srand(1000001); for( int i = 0; i < 10; i++ ) printf( "%d\n", rand() );

And here is the result:

21585 18586 29373 4301 3304 21158 23657 21142 2144 26110 ==== 21589 29335 14469 28364 13618 25085 26770 18215 18656 19962

As you can see, they diverge really quickly.

0 comments

chton11y ago

tfinnigaOP11y ago

Maybe the best way to get a feel for it is to take a look at this page of maze generators: http://weblog.jamisbuck.org/2011/2/7/maze-generation-algorit...

chton11y ago

That's a great page. I learned a lot, thanks!

j / k navigate · click thread line to collapse