for(var i = 0;i<playerArr.length;i++)
  {
    for(var j = 0;j<playerArr[i].bullets.length;j++)
    {
      playerArr[i].bullets[j].traveled += playerArr[i].bullets[j].speed;
      var x0 = playerArr[i].bullets[j].playerX;
      var y0 = playerArr[i].bullets[j].playerY;
      var radians = playerArr[i].bullets[j].attack * Math.PI / 180;
      var dX = playerArr[i].bullets[j].traveled * Math.cos(radians);
      var dY = playerArr[i].bullets[j].traveled * Math.sin(radians);
      var sShotSqr = playerArr[i].bullets[j].traveled * playerArr[i].bullets[j].traveled;

      // you'll need to track the last bullet position, or integrate this code
      // into the bullet update code so you can use both the previous and
      // current 'traveled' values.

      var tMin = playerArr[i].bullets[j].traveled-10 / playerArr[i].bullets[j].traveled;

      for(var k = 0;k<playerArr.length;k++)
      {
        var dXTarget = playerArr[k].x - x0;
        var dYTarget = playerArr[k].y - y0;
        var t = (dXTarget * dX + dYTarget * dY) / sShotSqr;
        // check for the bullet moving away from the player
        if (t < 0)
          continue;

        var radius = 15;
        var deltaTMax = radius / playerArr[i].bullets[j].traveled;
        // check coarsely for the player and bullet not crossing paths this frame
        if (t + deltaTMax < tMin || t - deltaTMax > 1)
          continue;

        var xSpoke = x0 + dX * t;
        var ySpoke = y0 + dY * t;
        var offsetSqr = radius * radius - xSpoke * xSpoke - ySpoke * ySpoke;
        // check for the bullet's path not touching the player
        if (offsetSqr < 0)
          continue;

        var deltaT = Math.sqrt(offsetSqr / sShotSqr);
        // check for the bullet not yet reaching the player or the player
        // moving across the path after the bullet has passed
        if (t + deltaT < tMin || t - deltaT > 1)
          continue;
        console.log("hit");
      }