Reduced bits used by net.Read/WritePlayer based on maxplayers

[mgetJane]

it is impossible for maxplayers to be changed without a server restart

also, i removed all the extra stuff from net.ReadPlayer because net.ReadUInt will never return a falsy value

also, changing net.WritePlayer into a single line is probably a little unnecessary, but imo it's harmless and i'll change it back if it's unwanted

[CornerPin]

math.log's second parameter is base, division by $\ln 2$ is unnecessary.

Suggested change

	local maxplayers_bits = math.ceil( math.log( 1 + game.MaxPlayers() ) / math.log( 2 ) )
	local maxplayers_bits = math.ceil( math.log( 1 + game.MaxPlayers(), 2 ) )

[mgetJane]

i remember an issue encountered by @2048khz-gachi-rmx where math.log(x, 2) gives an incorrect result while math.log(x) / math.log(2) gives the correct result

all their messages are gone from the gmod discord so i don't remember the exact details

[2048khz-gachi-rmx]

.ps BRANCH, ("%.17f"):format(math.log(4096, 2))
-- [Server]
"unknown"
"12.00000000000000000"
-- [Client]
"x86-64"
"11.99999999999999822"

.ps BRANCH, math.floor(math.log(4096, 2))
-- [Server]
"unknown"
12
-- [Client]
"x86-64"
11

[CornerPin]

https://github.com/LuaJIT/LuaJIT/commit/ad03eba715e5e0d0bd0f3c0ddef4b8f5bbb0c626 is the commit that caused this.
It seems that for values in $\left[ 1 .. 256 \right]$ it only causes issues when rounding down. Given that the function rounds up, it shouldn't be a problem.

> for p = 1, 8 do local log = math.log(2^p, 2) print(("%.17f / %i"):format(log, math.ceil(log))) end...
1.00000000000000000 / 1
2.00000000000000000 / 2
2.99999999999999956 / 3
4.00000000000000000 / 4
5.00000000000000000 / 5
5.99999999999999911 / 6
6.99999999999999911 / 7
8.00000000000000000 / 8

[mgetJane]

can you check the output of this? i'm on linux and the issue only happens on 64-bit windows

lua_run_cl for i=1,128 do if math.ceil(math.log(1+i,2))~=math.ceil(math.log(1+i)/math.log(2))then return print"bad"end end print"good"

[CornerPin]

] version
Protocol version 24
Exe version 2023.06.28 (garrysmod)
Exe build: 06:17:43 Apr  1 2024 (9246) (4000)
GMod version 2024.04.24, branch: x86-64, multicore: 1
Windows 64bit
] lua_run_cl for i=1,128 do if math.ceil(math.log(1+i,2))~=math.ceil(math.log(1+i)/math.log(2))then return print"bad"end end print"good"
good

[mgetJane]

still feels a little iffy to use something that's kinda unreliable

ttt has the bitsRequired function which is 100% reliable (and actually faster according to @figardo)

that function could be a good addition to either the math or util table