What does ~~ (“double tilde”) do in Javascript?

Question

I was checking out an online game physics library today and came across the ~~ operator. I know a single ~ is a bitwise NOT, would that make ~~ a NOT of a NOT, which would

Answer 1

Tilde(~) has an algorihm -(N+1)

For examle:

~0 = -(0+1) = -1
~5 = -(5+1) = -6
~-7 = -(-7+1) = 6

Double tilde is -(-(N+1)+1)

For example:

~~5 = -(-(5+1)+1) = 5
~~-3 = -(-(-3+1)+1) = -3

Triple tilde is -(-(-(N+1)+1)+1)

For example:

~~~2 = -(-(-(2+1)+1)+1) = -3
~~~3 = -(-(-(3+1)+1)+1) = -4