weird (numleafs+31)>>3 in SV_FatPVS

[ericw]

This is a bug/typo, right?

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fatbytes = (sv.worldmodel->numleafs+31)>>3;

https://github.com/id-Software/Quake/bl ... ain.c#L412

That gives the number of bytes for the bitvector, plus 3 bytes padding, which seems useless.
It should just be (numleafs+7)>>3 like all of the other PVS buffers?

There are some occurences of:

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4*((sv.worldmodel->numleafs+31)>>5);

in Quakeworld, which is rounding up to the nearest 4 byte boundary, so possibly that's where the typo came from.

[mh]

I think the intention is that it's to allow the following Q_memset to take it's fast path.

[ericw]

Yeah, I think it must have been an attempt to round up to the nearest multiple of 4, but even then it doesn't work as written:

>>> x = 12
>>> (x + 31) / 8
5