// Daniel Shiffman

// http://natureofcode.com

​

// Path Following

// Path is a just a straight line in this example

// Via Reynolds: // http://www.red3d.com/cwr/steer/PathFollow.html

​

// Using this variable to decide whether to draw all the stuff

let debug = false;

​

// A path object (series of connected points)

let path;

​

// Two vehicles

let vehicles = [];

​

function setup() {

  createCanvas(640, 360);

  newPath();

​

  // Each vehicle has different maxspeed and maxforce for demo purposes

  for (let i = 0; i < 120; i++) {

    newVehicle(random(width),random(height));

  }

}

​

function draw() {

  background(51);

  // Display the path

  path.display();

  vehicles.forEach( v => {

  // The boids follow the path

  v.follow(path);

  v.separate(vehicles);

  // Call the generic run method (update, borders, display, etc.)

  v.run();

  // Check if it gets to the end of the path since it's not a loop

  v.borders(path);

  });

  // Instructions

  fill(0);

  textAlign(CENTER);

  text("Hit 'd' to toggle debugging lines.\nClick the mouse to generate new vehicles.",width/2,height-20);

​

​

}

​

function newPath() {

  // A path is a series of connected points

  // A more sophisticated path might be a curve

  path = new Path();

  let offset = 30;

  path.addPoint(offset,offset);

  path.addPoint(width-offset,offset);

  path.addPoint(width-offset,height-offset);

  path.addPoint(width/2,height-offset*3);

  path.addPoint(offset,height-offset);

}

​

function newVehicle(x, y) {

  let maxspeed = random(2,4);

  let maxforce = 0.3;

  vehicles.push(new Vehicle(x,y,maxspeed,maxforce));

}

​

function keyPressed() {

  if (key == 'D') {

    debug = !debug;

  }

}

​

function mousePressed() {

  newVehicle(mouseX, mouseY);

}