gistfile1.txt

  "bodyVelocityLoopified": function bodyVelocityLoopified(index) {
    var pos = NBody.private.pos;
    var data = NBody.private.vel;
    
    var deltaTime = NBody.Constant.deltaTime;
    var epsSqr = NBody.Constant.epsSqr;
    var time = NBody.time;

    var shape = data.shape[0];

    var newVel;
    var newX, newY, newZ, newM;
    var newX2, newY2, newZ2, newM2;

    var cX = Math.cos(time / 22) * -4200;
    var cY = Math.sin(time / 14) * 9200;
    var cZ = Math.sin(time / 27) * 6000;

    // pull to center
    var maxDistance = 3400;
    var pullStrength = .042;

    var speedLimit = 8;

    // zones
    var zone = 400;
    var repel = 100;
    var align = 300;
    var attract = 100;


    if (time < 500) {
      speedLimit = .01;
      var attractPower = 100.9;
    }
    else {
      speedLimit = .01;
      attractPower = 10.9;
    }

    
    var zoneSqrd = zone * zone + zone * zone + zone * zone;

    var accX = 0, accY = 0, accZ = 0;
    var accX2 = 0, accY2 = 0, accZ2 = 0;
    var i;

    var debug = 0;

    // define particle 1 center distance
    var dirToCenterX = cX - pos.get(index)[0];
    var dirToCenterY = cY - pos.get(index)[1];
    var dirToCenterZ = cZ - pos.get(index)[2];

    var distanceSquaredTo = dirToCenterX * dirToCenterX + dirToCenterY * dirToCenterY + dirToCenterZ * dirToCenterZ;
    var distToCenter = Math.sqrt(distanceSquaredTo);

    // orient to center
    if (distToCenter > maxDistance) {

      var vel = (distToCenter - maxDistance) * pullStrength;
      if (time < 200)
        vel = .2;
      else vel = (distToCenter - maxDistance) * pullStrength;

      accX += (dirToCenterX / distToCenter) * vel;
      accY += (dirToCenterY / distToCenter) * vel;
      accZ += (dirToCenterZ / distToCenter) * vel;
    }



    for (i = 0; i < shape; i = i + 1) {

      // DIRS P1
      var rx = pos.get(i)[0] - pos.get(index)[0];
      var ry = pos.get(i)[1] - pos.get(index)[1];
      var rz = pos.get(i)[2] - pos.get(index)[2];

      // make shure we are not testing the particle against its own position
      var areSame = 0;
      if (pos.get(i)[0] == pos.get(index)[0] && pos.get(i)[1] == pos.get(index)[1] && pos.get(i)[2] == pos.get(index)[2])
        areSame += 1;

      var distSqrd = rx * rx + ry * ry + rz * rz;

      // cant use eqals to test, only <= or >= WTF
      if (distSqrd < zoneSqrd && areSame <= 0) {

        var length = Math.sqrt(distSqrd);
        var percent = distSqrd / zoneSqrd;

        if (distSqrd < align) { //align

          var threshDelta = align - repel;
          var adjustedPercent = (percent - repel) / threshDelta;
          var Q = (.5 - Math.cos(adjustedPercent * 3.14159265 * 2) * .5 + .5) * 100.9;


          // get velocity 2
          var velX2 = data.get(i)[4];
          var velY2 = data.get(i)[5];
          var velZ2 = data.get(i)[6];

          var velLength2 = Math.sqrt(velX2 * velX2 + velY2 * velY2 + velZ2 * velZ2);

          // normalize vel2 and multiply by factor
          velX2 = (velX2 / velLength2) * Q;
          velY2 = (velY2 / velLength2) * Q;
          velZ2 = (velZ2 / velLength2) * Q;

          // get own velocity
          var velX = data.get(i)[0];
          var velY = data.get(i)[1];
          var velZ = data.get(i)[2];

          var velLength = Math.sqrt(velX * velX + velY * velY + velZ * velZ);

          // normalize own velocity
          velX = (velX / velLength) * Q;
          velY = (velY / velLength) * Q;
          velZ = (velZ / velLength) * Q;

          accX += velX2;
          accY += velY2;
          accZ += velZ2;

          accX2 += velX;
          accY2 += velY;
          accZ2 += velZ;


        } else { // attract
          var threshDelta2 = 1 - align;
          var adjustedPercent2 = (percent - align) / threshDelta2;
          var C = (1 - (Math.cos(adjustedPercent2 * 3.14159265 * 2) * 0.5 + 0.5)) * attractPower;

          // normalize the distance vector
          var dx = (rx / (length)) * C;
          var dy = (ry / (length)) * C;
          var dz = (rz / (length)) * C;


          debug = 1.1;


          accX += dx;
          accY += dy;
          accZ += dz;

          accX2 -= dx;
          accY2 -= dy;
          accZ2 -= dz;

        }

      }

    }

    // Speed limits

    var accSquared = accX * accX + accY * accY + accZ * accZ;
    if (accSquared > speedLimit) {

      accX = accX * .015;
      accY = accY * .015;
      accZ = accZ * .015;


    }

    var accSquared2 = accX2 * accX2 + accY2 * accY2 + accZ2 * accZ2;
    if (accSquared2 > speedLimit) {

      accX2 = accX2 * .015;
      accY2 = accY2 * .015;
      accZ2 = accZ2 * .015;
    }


    // Caclulate new velocity
    newX = (data.get(index)[0]) + accX;
    newY = (data.get(index)[1]) + accY;
    newZ = (data.get(index)[2]) + accZ;

    newX2 = (data.get(index)[3]) + accX2;
    newY2 = (data.get(index)[4]) + accY2;
    newZ2 = (data.get(index)[5]) + accZ2;


    return [newX, newY, newZ, newX2, newY2, newZ2];
  },