dy <<= 1;
dx <<= 1;
That’s some C++ code I found, what does it do to the variables, and what is that operator called?
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dy <<= 1;
dx <<= 1;
That’s some C++ code I found, what does it do to the variables, and what is that operator called?
That shifts
dyanddx1 bit to the left.It’s equivalent to (unless dy and dx have operator =<< overloaded)
If
dxanddyare integral types, it’s equivalent to multipication by 2.Note that it is undefined behavior to left-shift a negative number.
This is an ugly hack by programmers who think this is more efficient than just multiplying by 2 (which is not, but it is a lot less readable).