<canvas id="canvas">Canvas not supported.</canvas>
<ul id="navigation">
  <li>Please keep moving the mouse.</li>
</ul>

* {
  margin: 0;
  padding: 0;
  color: #FFF;
}

canvas#canvas {
  display: block;
  background: #000;
}

ul#navigation {
  position: absolute;
  height: 100%;
  top: 0;
  right: 0;
  text-align: center;
  margin-right: 1.6rem;
  font-size: 0.8rem;
  -webkit-writing-mode: vertical-rl;
      -ms-writing-mode: tb-rl;
          writing-mode: vertical-rl;
}

ul#navigation > li {
  display: inline-block;
}

(function () {
  'use strict';
  window.addEventListener('load', function () {
    var canvas = document.getElementById('canvas');

    if (!canvas || !canvas.getContext) {
      return false;
    }

    /********************
      Random Number
    ********************/

    function rand(min, max) {
      return Math.floor(Math.random() * (max - min + 1) + min);
    }

    /********************
      Var
    ********************/

    var ctx = canvas.getContext('2d');
    var X = canvas.width = window.innerWidth;
    var Y = canvas.height = window.innerHeight;
    var mouseX = null;
    var mouseY = null;
    var dist = 80;
    var lessThan = Math.sqrt(dist * dist + dist * dist);
    var mouseDist = 150;
    var shapeNum;
    var shapes = [];
    var ease = 0.3;
    var friction = 0.9;
    var lineWidth = 5;
    X > Y ? shapeNum = X / dist : shapeNum = Y / dist;

    if (X < 768) {
      lineWidth = 2;
      dist = 40;
      lessThan = Math.sqrt(dist * dist + dist * dist);
      mouseDist = 50;
      X > Y ? shapeNum = X / dist : shapeNum = Y / dist;
    }

    /********************
      Animation
    ********************/

    window.requestAnimationFrame =
      window.requestAnimationFrame ||
      window.mozRequestAnimationFrame ||
      window.webkitRequestAnimationFrame ||
      window.msRequestAnimationFrame ||
      function(cb) {
        setTimeout(cb, 17);
      };

    /********************
      Shape
    ********************/
    
    function Shape(ctx, x, y, i) {
      this.ctx = ctx;
      this.init(x, y, i);
    }
    
    Shape.prototype.init = function(x, y, i) {
      this.x = x;
      this.y = y;
      this.xi = x;
      this.yi = y;
      this.i = i;
      this.r = 1;
      this.v = {
        x: 0,
        y: 0
      };
      this.c = rand(0, 360);
    };

    Shape.prototype.draw = function() {
      var ctx  = this.ctx;
      ctx.save();
      ctx.fillStyle = 'hsl(' + this.c + ', ' + '80%, 60%)';
      ctx.beginPath();
      ctx.arc(this.x, this.y, this.r, 0, Math.PI * 2, false);
      ctx.fill();
      ctx.restore();
    };

    Shape.prototype.mouseDist = function() {
      var x = mouseX - this.x;
      var y = mouseY - this.y;
      var d = x * x + y * y;
      var dist = Math.sqrt(d);
      if (dist < mouseDist) {
        this.v.x = +this.v.x;
        this.v.y = +this.v.y;
        var colAngle = Math.atan2(mouseY - this.y, mouseX - this.x);
        this.v.x = -Math.cos(colAngle) * 5;
        this.v.y = -Math.sin(colAngle) * 5;
        this.x += this.v.x;
        this.y += this.v.y;
      } else if (dist > mouseDist && dist < mouseDist + 10) {
        this.v.x = 0;
        this.v.y = 0;
      } else {
        this.v.x += (this.xi - this.x) * ease;
        this.v.y += (this.yi - this.y) * ease;
        this.v.x *= friction;
        this.v.y *= friction;
        this.x += this.v.x;
        this.y += this.v.y;
      }
    };

    Shape.prototype.drawLine = function(i) {
      var j = i;
      for (var i = 0; i < shapes.length; i++) {
        if (j !== i) {
          var x = this.x - shapes[i].x;
          var y = this.y - shapes[i].y;
          var d = x * x + y * y;
          var dist = Math.floor(Math.sqrt(d));
          if (dist <= lessThan) {
            ctx.save();
            ctx.lineWidth = lineWidth;
            ctx.strokeStyle = 'hsl(' + this.c + ', ' + '80%, 60%)';
            ctx.beginPath();
            ctx.moveTo(this.x, this.y);
            ctx.lineTo(shapes[i].x, shapes[i].y);
            ctx.stroke();
            ctx.restore();
          }
        }
      }
    };

    Shape.prototype.render = function(i) {
      this.drawLine(i);
      if (mouseX !== null) this.mouseDist();
      this.draw();
    };
    
    for (var i = 0; i < shapeNum + 1; i++) {
      for (var j = 0; j < shapeNum + 1; j++) {
        if (j * dist - dist > Y) break;
        var s = new Shape(ctx, i * dist, j * dist, i, j);
        shapes.push(s);
      }
    }
   
    /********************
      Render
    ********************/
    
    function render() {
      ctx.clearRect(0, 0, X, Y);
      for (var i = 0; i < shapes.length; i++) {
        shapes[i].render(i);
      }
      requestAnimationFrame(render);
    }

    render();

    /********************
      Event
    ********************/
    
    function onResize() {
      X = canvas.width = window.innerWidth;
      Y = canvas.height = window.innerHeight;
      shapes = [];
      if (X < 768) {
        lineWidth = 2;
        dist = 40;
        lessThan = Math.sqrt(dist * dist + dist * dist);
        mouseDist = 50;
        X > Y ? shapeNum = X / dist : shapeNum = Y / dist;
      } else {
        lineWidth = 5;
        dist = 80;
        lessThan = Math.sqrt(dist * dist + dist * dist);
        mouseDist = 150;
        X > Y ? shapeNum = X / dist : shapeNum = Y / dist;
      }
      for (var i = 0; i < shapeNum + 1; i++) {
        for (var j = 0; j < shapeNum + 1; j++) {
          if (j * dist - dist > Y) break;
          var s = new Shape(ctx, i * dist, j * dist, i, j);
          shapes.push(s);
        }
      }
    }

    window.addEventListener('resize', function() {
      onResize();
    });

    window.addEventListener('mousemove', function(e) {
      mouseX = e.clientX;
      mouseY = e.clientY;
    }, false);

    canvas.addEventListener('touchmove', function(e) {
      var touch = e.targetTouches[0];
      mouseX = touch.pageX;
      mouseY = touch.pageY;
    });

  });
  // Author
  console.log('File Name / net.js\nCreated Date / July 11, 2020\nAuthor / Toshiya Marukubo\nTwitter / https://twitter.com/toshiyamarukubo');
})();