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[Dwarf4Explosives]

So, as many modders have found, there's a size limit (for creatures) of approximately 2 billion cubic centimeters. Is this a direct result of the way the game works, or is it a cap that Toady has placed there on purpose?

[StupidElves]

I think that this would be better suited in the modding section. But I do think that it is probably both.

[Bloax]

Two billion is just about 2^31, which would make it pretty much at the edge of 32-bit math - and also likely why everyone is seeing overflows when creatures get bigger than that, since 2^32 is 4.294967 billion.

If you want a reference on just how big two billion is, then it's a 12.59 meter cube - with humans being a 41.21 centimeter cube - or simply put a cube 30 times larger than a human.
Of course that's not stupendously huge, but it's still absolutely massive. (And mind you, that statue is only ~30 meters tall, so it's probably somewhere along 16 times larger than a human.)

[Dwarf4Explosives]

So it's limited by the game mechanics then. That's what I thought. Too bad. I'm guessing that will change though if Toady ever figures out how to make DF 64-bit.

[Putnam]

Having a 64-bit integer has nothing to do with your program itself being 32-bit.

[utunnels]

Two billion is just about 2^31, which would make it pretty much at the edge of 32-bit math - and also likely why everyone is seeing overflows when creatures get bigger than that, since 2^32 is 4.294967 billion.

If you want a reference on just how big two billion is, then it's a 12.59 meter cube - with humans being a 41.21 centimeter cube - or simply put a cube 30 times larger than a human.
Of course that's not stupendously huge, but it's still absolutely massive. (And mind you, that statue is only ~30 meters tall, so it's probably somewhere along 16 times larger than a human.)

Which is about 28000 times bigger than a human in volume. Imagine a crowd of 28000 soldiers fighting a colossus this size?

[IndigoFenix]

It would be nice for there to be an integer cap to prevent overflow, so we wouldn't get things like semighostly giant sperms whales.

[Dwarf4Explosives]

Having a 64-bit integer has nothing to do with your program itself being 32-bit.

So is there a specific reason why Toady chose to use 32-bit math for size calculations? I don't know all that much about programming, to be honest.

[Dirst]

It would be nice for there to be an integer cap to prevent overflow, so we wouldn't get things like semighostly giant sperms whales.

C-like languages get their good runtime performance by not checking things like this.  You can allocate an array of ten items and reference the fifteenth without throwing in error.  Of course this can lead to Bad Things, but when the program is written "properly" then the lack of checks makes things run faster.

[Uronym]

Having a 64-bit integer has nothing to do with your program itself being 32-bit.

So is there a specific reason why Toady chose to use 32-bit math for size calculations? I don't know all that much about programming, to be honest.

He probably wasn't thinking too hard about it. He probably thought it was quite large enough at the time. 32-bit is the standard size for integers, pretty much.

[Putnam]

Having a 64-bit integer has nothing to do with your program itself being 32-bit.

So is there a specific reason why Toady chose to use 32-bit math for size calculations? I don't know all that much about programming, to be honest.

probably something simple like "nah, it doesn't need to be a long long".

[Thief^]

64-bit integer calculations on a 32-bit processor come with a significant performance penalty, particularly with multiplication* or division. Add to that the double memory cost, and you only use 64-bit numbers when you have to.

*multiplying 32-bit * 32-bit = 64-bit result is actually an instruction in x86, but 64-bit values actually in the multiply is bad

On a 64-bit processor (or using extensions like SSE that can natively handle 64-bit numbers) this is much less of an issue.

[TheDarkStar]

If you divided the size of everything by something (like 10 or 100), could you get bigger creatures?

[Uronym]

If you divided the size of everything by something (like 10 or 100), could you get bigger creatures?

Of course. It might mean a lot of changes in the code, though, depending on how he did it. Or not.

[Thief^]

If you divided the size of everything by something (like 10 or 100), could you get bigger creatures?

You'd have to make sure that weights and strengths and densities were proportionally correct, but sure.