{

  constructor(t)

  {

    if (t != 1)

      this.weights = [random(-1, 1), random(-1, 1), random(-1, 1)];

      //            FORWARD RIGHT LEFT

    else this.weights = [];

    this.fitness = 0;

    this.grid = [];

    for (let i = 0; i < width/scl + 2; i++)

    {

      this.grid.push([]);

      for (let j = 0; j < height/scl + 2; j++)

        this.grid[i].push((i == 0 || j == 0 || i == width/scl + 1 || j == height/scl + 1) ? 0 : 1);

    }

    this.dir = createVector(-1, 0);

    this.pointer = 2;

    this.dead = false;

    this.pos = createVector(4, 4);

    this.tail = [createVector(5 * scl + scl / 2, 4 * scl + scl / 2), createVector(6 * scl + scl / 2, 4 * scl + scl / 2), createVector(7 * scl + scl / 2, 4 * scl + scl / 2)];

    {

      this.grid[4+1][4+1] = 0; 

      this.grid[5+1][4+1] = 0; 

      this.grid[6+1][4+1] = 0; 

      this.grid[7+1][4+1] = 0;

    }

  }

  display()

  {

    noStroke();

    fill(200);

    ellipse(this.pos.x * scl + scl / 2, this.pos.y * scl + scl / 2, segmSize); 

    for (let segm of this.tail)

      ellipse(segm.x, segm.y, segmSize);

    // for (let i = 0; i < width/scl + 2; i++)

    //   for (let j = 0; j < height/scl + 2; j++)

    //     if (this.grid[i][j] == 0) 

    //     {

    //      push();

    //       fill(0,255,0);

    //       rect(i*scl-scl, j*scl-scl, scl, scl);

    //       pop();

    //     }

  }

  move(dir)

  { 

    let temp = this.tail.pop();

    temp.x = (temp.x - scl / 2) / scl;

    temp.y = (temp.y - scl / 2) / scl;

    this.grid[temp.x+1][temp.y+1] = 1;

    this.tail.unshift(createVector(this.pos.x * scl + scl / 2, this.pos.y * scl + scl / 2));

    switch (dir)

    {

      case 0:

        break;

      case 1:

        if (this.dir.x == 1) {this.dir.set(0, 1); this.pointer = 1}

        else if (this.dir.x == -1) {this.dir.set(0, -1); this.pointer = 3}

        else if (this.dir.y == 1) {this.dir.set(-1, 0);  this.pointer = 2}

        else if (this.dir.y == -1) {this.dir.set(1, 0);  this.pointer = 0}

        break;

      case -1:

        if (this.dir.x == 1) {this.dir.set(0, -1); this.pointer = 3}

        else if (this.dir.x == -1) {this.dir.set(0, 1); this.pointer = 1}

        else if (this.dir.y == 1) {this.dir.set(1, 0);  this.pointer = 0}

        else if (this.dir.y == -1) {this.dir.set(-1, 0);  this.pointer = 2}

        break;

    }

    this.pos.add(this.dir);

    this.grid[this.pos.x+1][this.pos.y+1] = 0;

    this.dead = (this.pos.x <= 0 || this.pos.y <= 0 || this.pos.x >= wEdge || this.pos.y >= hEdge);

  }

  decide()

  {

    if (this.dead) return 0;

    let val;

    switch(this.pointer)

    {

      case 0:

        val = this.weights[0] * this.grid[this.pos.x + 2][this.pos.y + 1] +

              this.weights[1] * this.grid[this.pos.x + 1][this.pos.y + 2] +

              this.weights[2] * this.grid[this.pos.x + 1][this.pos.y    ];

        break;

      case 1:

        val = this.weights[0] * this.grid[this.pos.x + 1][this.pos.y + 2] +

              this.weights[1] * this.grid[this.pos.x    ][this.pos.y + 1] +

              this.weights[2] * this.grid[this.pos.x + 2][this.pos.y + 1];

        break;

      case 2:

        val = this.weights[0] * this.grid[this.pos.x    ][this.pos.y + 1] +

              this.weights[1] * this.grid[this.pos.x + 1][this.pos.y    ] +

              this.weights[2] * this.grid[this.pos.x + 1][this.pos.y + 2];

        break;

      case 3:

        val = this.weights[0] * this.grid[this.pos.x + 1][this.pos.y    ] +

              this.weights[1] * this.grid[this.pos.x + 2][this.pos.y + 1] +

              this.weights[2] * this.grid[this.pos.x    ][this.pos.y + 1];

        break;

    }

    val = round(Math.tanh(val));

    this.move(val);

  }

  checkFitness()

  {

    if (this.dead) this.fitness = 0;

    else this.fitness = this.tail.length;

    return this.fitness;

  }

}