Posts tagged "performance"

So you have some number, x, which you want to round to the nearest integer. Easy, right?

x = Math.round(x);

Sure, but is this the fastest option? I think not.

x = x < 0 ? x - 0.5 >> 0 : x + 0.5 >> 0;

What the heck's going on here? >> is JavaScript's right shift operator. It shifts a number's binary representation n bits to the right, where n is the value to the right of the operator. Since n is 0 in this case, no shifting will occur, although the resulting value will be an integer.

Note that this approach results in -82.5 being rounded to -83.

If, for some reason, your code calls Math.round() millions of times, it may be worth investigating the bitwise approach to avoid the overhead of all those function calls.

Stick to Math.round() the rest of the time, though, as it makes for much clearer code. Never optimize prematurely.

In this performance from Ukraine's Got Talent, Kseniya Simonova uses the simplest of tools (a lightbox, sand, and her own body) to create a captivating animation. I really enjoyed the accompanying "Nothing Else Matters" instrumental, as well.