Run results for: trigata

Run details:

User agent: Mozilla/5.0 (Windows NT 6.3; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/66.0.3359.139 Safari/537.36

Browser: Chrome 66

Operating system: Windows 8.1

Device Platform: Other

Date tested: 5 years ago

Test name	Executions per second
native	864737.1 Ops/sec
alt	802251.6 Ops/sec
alt2	806414.8 Ops/sec
alt3	816304.6 Ops/sec
alt4	612901.6 Ops/sec

Script Preparation code:

function rand(min, max) {
    return Math.floor(Math.random() * (max - min + 1)) + min;
}

function angle(x, y) {
  let result = Math.atan(y / x);
  if (x < 0) {
    result += Math.PI;
  } else if (y < 0) {
    result += 2 * Math.PI;
  }
  return result;
}

function angle2(x, y) {
    if (x == 0)
      return (y == 0) ? 0 : (y > 0 ? Math.PI/2 : -Math.PI/2)
  
    var atan_xy = Math.atan(y / x)
    if (x > 0)
      return atan_xy
    else // x < 0
      return atan_xy + (y < 0 ? -Math.PI : Math.PI)
}

function myAtan2(a, b)
{
    var atan2val;
    if (b > 0) {
        atan2val = Math.atan(a/b);
    }
    else if ((b < 0) && (a >= 0)) {
        atan2val = Math.atan(a/b) + Math.PI;
    }
    else if ((b < 0) && (a < 0)) {
        atan2val = Math.atan(a/b) - Math.PI;
    }
    else if ((b = 0) && (a > 0)) {
        atan2val = Math.PI / 2;
    }
    else if ((b = 0) && (a < 0)) {
        atan2val = 0 - (Math.PI / 2 );
    }
    else if ((b = 0) && (a = 0)) {
        atan2val = 1000;
    }
  
    return atan2val;
}

function matan2(y, x){
  const c1 = Math.PI / 4;
  const c2 = Math.PI * 3 / 4;

  if (y == 0 && x == 0){
    return 0;
  }

  const abs_y = Math.abs(y);
  let angle;
  if (x >= 0){
    angle = c1 - c1 * ((x - abs_y) / (x + abs_y));
  } else {
    angle = c2 - c1 * ((x + abs_y) / (abs_y - x));
  }

  if (y < 0){
    return -angle;
  }

  return angle;
}

Tests:

native
var xO = rand(1, 1000); var yO = rand(1, 1000); Math.atan(yO, xO);
alt
var xT = rand(1, 1000); var yT = rand(1, 1000); angle(xT, yT);
alt2
var xD = rand(1, 1000); var yD = rand(1, 1000); angle2(xD, yD);
alt3
var xC = rand(1, 1000); var yC = rand(1, 1000); myAtan2(xC, yC);
alt4
var xZ = rand(1, 1000); var yZ = rand(1, 1000); matan2(xZ, yZ);

native

alt

alt2

alt3

alt4