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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

HTML

              
                <canvas id="canvas"></canvas>
<h1>Happy Halloween!</h1>
              
            
!

CSS

              
                @import url(https://fonts.googleapis.com/css?family=Euphoria+Script);

html, body{
  width: 100%;
  height: 100%;
  background: #ff8833;
  overflow: hidden;
  text-rendering: optimizeLegibility;
}

canvas{
  display: block;
  background: #ff8833;
}

h1 {
  position: absolute;
  z-index: 1;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  height: 80px;
  text-align: center;
  margin: auto;
  font-family: 'Euphoria Script';
  font-size: 80px;
  color: rgba(104, 54, 0, 0.6);
}
              
            
!

JS

              
                // A simple experiment regarding birds flocking.

var Vector = (function () {
    function Vector(x, y) {
        if (typeof x === "undefined") { x = 0; }
        if (typeof y === "undefined") { y = 0; }
        this.x = x;
        this.y = y;
    }
    Vector.prototype.clone = function () {
        return new Vector(this.x, this.y);
    };
    Vector.prototype.zero = function () {
        this.x = this.y = 0;
        return this;
    };
    Object.defineProperty(Vector.prototype, "zeroed", {
        get: function () {
            return (this.x === 0 && this.y === 0);
        },
        enumerable: true,
        configurable: true
    });
    Object.defineProperty(Vector.prototype, "length", {
        get: function () {
            return Math.sqrt(this.lengthSq);
        },
        set: function (value) {
            var a = this.angle;
            this.x = Math.cos(a) * value;
            this.y = Math.sin(a) * value;
        },
        enumerable: true,
        configurable: true
    });
    Object.defineProperty(Vector.prototype, "lengthSq", {
        get: function () {
            return this.x * this.x + this.y * this.y;
        },
        enumerable: true,
        configurable: true
    });
    Object.defineProperty(Vector.prototype, "angle", {
        get: function () {
            return Math.atan2(this.y, this.x);
        },
        set: function (value) {
            var length = this.length;
            this.x = Math.cos(value) * length;
            this.y = Math.sin(value) * length;
        },
        enumerable: true,
        configurable: true
    });
    Vector.prototype.normalize = function () {
        if(this.length === 0) {
            this.x = 1;
            return this;
        }
        var length = this.length;
        this.x /= length;
        this.y /= length;
        return this;
    };
    Vector.prototype.truncate = function (max) {
        this.length = Math.min(max, this.length);
        return this;
    };
    Vector.prototype.reverse = function () {
        this.x = -this.x;
        this.y = -this.y;
        return this;
    };
    Object.defineProperty(Vector.prototype, "normalized", {
        get: function () {
            return this.length == 1;
        },
        enumerable: true,
        configurable: true
    });
    Vector.prototype.dotProduct = function (vector) {
        return this.x * vector.x + this.y * vector.y;
    };
    Vector.angleBetween = function angleBetween(vector1, vector2) {
        if(!vector1.normalized) {
            vector1 = vector1.clone().normalize();
        }
        if(!vector2.normalized) {
            vector2 = vector2.clone().normalize();
        }
        return Math.acos(vector1.dotProduct(vector2));
    };
    Object.defineProperty(Vector.prototype, "perpendicular", {
        get: function () {
            return new Vector(-this.y, this.x);
        },
        enumerable: true,
        configurable: true
    });
    Vector.prototype.sign = function (vector) {
        return this.perpendicular.dotProduct(vector) < 0 ? -1 : 1;
    };
    Vector.prototype.dist = function (vector) {
        return Math.sqrt(this.distSq(vector));
    };
    Vector.prototype.distSq = function (vector) {
        var dx = vector.x - this.x;
        var dy = vector.y - this.y;
        return dx * dx + dy * dy;
    };
    Vector.prototype.add = function (vector) {
        return new Vector(this.x + vector.x, this.y + vector.y);
    };
    Vector.prototype.subtract = function (vector) {
        return new Vector(this.x - vector.x, this.y - vector.y);
    };
    Vector.prototype.multiply = function (value) {
        return new Vector(this.x * value, this.y * value);
    };
    Vector.prototype.divide = function (value) {
        return new Vector(this.x / value, this.y / value);
    };
    Vector.prototype.equals = function (vector) {
        return this.x === vector.x && this.y === vector.y;
    };
    return Vector;
})();
var Vehicle = (function () {
    function Vehicle() {
        this.mass = 1.0;
        this.maxSpeed = 10;
        this.position = new Vector();
        this.velocity = new Vector();
    }
    Vehicle.WRAP = "wrap";
    Vehicle.BOUNCE = "bounce";
    Vehicle.prototype.draw = function (context) {
        context.save();
        context.translate(this.position.x, this.position.y);
        context.rotate(this.velocity.angle);
      
        //This is where I draw them as candy corn :)
        context.fillStyle = "#ff4814";
        context.beginPath();
        context.moveTo(this.size, 0);
        context.lineTo(-this.size, this.size / 2);
        context.lineTo(-this.size, -this.size / 2);
        context.lineTo(this.size, 0);
        context.fill();
      
        context.fillStyle = "#ffcd2d";
        context.beginPath();
        context.moveTo(this.size, 0);
        context.lineTo(-this.size * 0.5, this.size / 2 * 0.8);
        context.lineTo(-this.size * 0.5, -this.size / 2 * 0.8);
        context.lineTo(this.size, 0);
        context.fill();

        context.fillStyle = "#eeeeee";
        context.beginPath();
        context.moveTo(this.size, 0);
        context.lineTo(Math.floor(-this.size * 0.1) + 7, this.size / 2 * 0.3);
        context.lineTo(Math.floor(-this.size * 0.1) + 7, -this.size / 2 * 0.3);
        context.lineTo(this.size, 0);
        context.fill();

        context.restore();
    };
    Vehicle.prototype.update = function (width, height) {
        this.velocity = this.velocity.truncate(this.maxSpeed);
        this.position = this.position.add(this.velocity);
        if(this.edgeBehavior == Vehicle.WRAP) {
            this.wrap(width, height);
        } else if(this.edgeBehavior == Vehicle.BOUNCE) {
            this.bounce(width, height);
        }
    };
    Vehicle.prototype.bounce = function (width, height) {
        if(this.position.x > width) {
            this.position.x = width;
            this.velocity.x *= -1;
        } else if(this.position.x < 0) {
            this.position.x = 0;
            this.velocity.x *= -1;
        } else if(this.position.y > height) {
            this.position.y = height;
            this.velocity.y *= -1;
        } else if(this.position.y < 0) {
            this.position.y = 0;
            this.velocity.y *= -1;
        }
    };
    Vehicle.prototype.wrap = function (width, height) {
        if(this.position.x > width) {
            this.position.x = 0;
        }
        if(this.position.x < 0) {
            this.position.x = width;
        }
        if(this.position.y > height) {
            this.position.y = 0;
        }
        if(this.position.y < 0) {
            this.position.y = height;
        }
    };
    return Vehicle;
})();
var __extends = this.__extends || function (d, b) {
    function __() { this.constructor = d; }
    __.prototype = b.prototype;
    d.prototype = new __();
};
var SteeringVehicle = (function (_super) {
    __extends(SteeringVehicle, _super);
    function SteeringVehicle() {
        _super.call(this);
        this.maxForce = 1;
        this.arrivalThreshold = 100;
        this.wanderRadius = 5;
        this.wanderAngle = 0;
        this.wanderRange = 1;
        this.wanderDistance = 10;
        this.avoidDistance = 300;
        this.avoidBuffer = 20;
        this.pathIndex = 0;
        this.pathThreshold = 20;
        this.tooCloseDist = 60;
        this.inSightDist = 200;
        this.steeringForce = new Vector();
    }
    SteeringVehicle.prototype.seek = function (target) {
        var desiredVelocity = target.subtract(this.position);
        desiredVelocity.normalize();
        desiredVelocity = desiredVelocity.multiply(this.maxSpeed);
        var force = desiredVelocity.subtract(this.velocity);
        this.steeringForce = this.steeringForce.add(force);
    };
    SteeringVehicle.prototype.flee = function (target) {
        var desiredVelocity = target.subtract(this.position);
        desiredVelocity.normalize();
        desiredVelocity = desiredVelocity.multiply(this.maxSpeed);
        var force = desiredVelocity.subtract(this.velocity);
        this.steeringForce = this.steeringForce.subtract(force);
    };
    SteeringVehicle.prototype.arrive = function (target) {
        var desiredVelocity = target.subtract(this.position);
        desiredVelocity.normalize();
        var dist = this.position.dist(target);
        if(dist > this.arrivalThreshold) {
            desiredVelocity = desiredVelocity.multiply(this.maxSpeed);
        } else {
            desiredVelocity = desiredVelocity.multiply(this.maxSpeed * dist / this.arrivalThreshold);
        }
        var force = desiredVelocity.subtract(this.velocity);
        this.steeringForce = this.steeringForce.add(force);
    };
    SteeringVehicle.prototype.pursue = function (target) {
        var lookAheadTime = this.position.dist(target.position) / this.maxSpeed;
        var predictedTarget = target.position.add(target.velocity.multiply(lookAheadTime));
        this.seek(predictedTarget);
    };
    SteeringVehicle.prototype.evade = function (target) {
        var lookAheadTime = this.position.dist(target.position) / this.maxSpeed;
        var predictedTarget = target.position.add(target.velocity.multiply(lookAheadTime));
        this.flee(predictedTarget);
    };
    SteeringVehicle.prototype.wander = function () {
        var center = this.velocity.clone().normalize().multiply(this.wanderDistance);
        var offset = new Vector();
        offset.length = this.wanderRadius;
        offset.angle = this.wanderAngle;
        this.wanderAngle += Math.random() * this.wanderRange - this.wanderRange * 0.5;
        var force = center.add(offset);
        this.steeringForce = this.steeringForce.add(force);
    };
    SteeringVehicle.prototype.avoid = function (targets) {
        for(var i = 0, l = targets.length; i < l; i++) {
            var target = targets[i];
            var heading = this.velocity.clone().normalize();
            var difference = target.position.subtract(this.position);
            var dotProd = difference.dotProduct(heading);
            if(dotProd > 0) {
                var feeler = heading.multiply(this.avoidDistance);
                var projection = heading.multiply(dotProd);
                var dist = projection.subtract(difference).length;
                if(dist < target.size + this.avoidBuffer && projection.length < feeler.length) {
                    var force = heading.multiply(this.maxSpeed);
                    force.angle += difference.sign(this.velocity) * Math.PI / 2;
                    force = force.multiply(1 - projection.length / feeler.length);
                    this.steeringForce = this.steeringForce.add(force);
                    this.velocity = this.velocity.multiply(projection.length / feeler.length);
                }
            }
        }
    };
    SteeringVehicle.prototype.path = function (path, loop) {
        if (typeof loop === "undefined") { loop = false; }
        var point = path[this.pathIndex];
        if(point == null) {
            return;
        }
        if(this.position.dist(point) < this.pathThreshold) {
            if(this.pathIndex >= path.length - 1) {
                if(loop) {
                    this.pathIndex = 0;
                }
            } else {
                this.pathIndex++;
            }
        }
        if(this.pathIndex >= path.length - 1 && !loop) {
            this.arrive(point);
        } else {
            this.seek(point);
        }
    };
    SteeringVehicle.prototype.flock = function (flock) {
        var averageVelocity = this.velocity.clone();
        var averagePosition = new Vector();
        var inSightCount = 0;
        for(var i = 0, l = flock.length; i < l; i++) {
            var vehicle = flock[i];
            if(vehicle != this && this.inSight(vehicle)) {
                averageVelocity = averageVelocity.add(vehicle.velocity);
                averagePosition = averagePosition.add(vehicle.position);
                if(this.tooClose(vehicle)) {
                    this.flee(vehicle.position);
                }
                inSightCount++;
            }
        }
        if(inSightCount > 0) {
            averageVelocity = averageVelocity.divide(inSightCount);
            averagePosition = averagePosition.divide(inSightCount);
            this.seek(averagePosition);
            this.steeringForce.add(averageVelocity.subtract(this.velocity));
        }
    };
    SteeringVehicle.prototype.inSight = function (vehicle) {
        if(this.position.dist(vehicle.position) > this.inSightDist) {
            return false;
        }
        var heading = this.velocity.clone().normalize();
        var difference = vehicle.position.subtract(this.position);
        var dotProd = difference.dotProduct(heading);
        if(dotProd < 0) {
            return false;
        }
        return true;
    };
    SteeringVehicle.prototype.tooClose = function (vehicle) {
        return this.position.dist(vehicle.position) < this.tooCloseDist;
    };
    SteeringVehicle.prototype.update = function (width, height) {
        this.steeringForce = this.steeringForce.truncate(this.maxForce);
        this.steeringForce = this.steeringForce.divide(this.mass);
        this.velocity = this.velocity.add(this.steeringForce);
        this.steeringForce = new Vector();
        _super.prototype.update.call(this, width, height);
    };
    return SteeringVehicle;
})(Vehicle);
var Playground = (function () {
    function Playground() {
        this.mouseX = 0;
        this.mouseY = 0;
        this.pinned = true;
        this.color = "#ffffff";
        var canvas = document.querySelector("#canvas");
        this.context = canvas.getContext("2d");
        this.context.lineWidth = 1;
        this.resize();
        this.init();
        window.addEventListener('resize', this.resize.bind(this));
        this.animate();
    }
    Playground.prototype.init = function () {
        this.birds = [];
        this.flockQuantity = 25; //Number of boids
        for(var i = 0; i < this.flockQuantity; i++) {
            this.birds[i] = new SteeringVehicle();
            this.birds[i].size = 20; //Size of boids
            this.birds[i].position = new Vector(Math.random() * this.width, Math.random() * this.height);
            this.birds[i].mass = 2; //Boid mass
            this.birds[i].velocity.length = 3;
            this.birds[i].velocity.angle = Math.PI / 5;
            this.birds[i].edgeBehavior = Vehicle.WRAP;
        }
    };
    Playground.prototype.onMouseMove = function (e) {
        this.mouseX = e.clientX;
        this.mouseY = e.clientY;
    };
    Playground.prototype.resize = function () {
        this.width = window.innerWidth;
        this.height = window.innerHeight;
        this.context.canvas.width = this.width;
        this.context.canvas.height = this.height;
    };
    Playground.prototype.animate = function () {
        this.context.clearRect(0, 0, this.width, this.height);
        this.context.fillStyle = this.context.strokeStyle = this.color;
        this.context.globalCompositeOperation = "source-over";
        for(var i = 0; i < this.flockQuantity; i++) {
            this.birds[i].flock(this.birds);
            this.birds[i].update(this.width, this.height);
            this.birds[i].draw(this.context);
        }
        requestAnimationFrame(this.animate.bind(this));
    };
    return Playground;
})();
var Run = (function () {
    function Run() {
        var playground = new Playground();
    }
    return Run;
})();
var run = new Run();

              
            
!
999px

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