refactor this hideous mess of code into just a list of vectors 

 where each vector has a range and (delta) speed it can move at (x-axis only)

​

*/

​

var target;

var targetsTarget;

var TARGET_SPEED = 1;

​

var hero;

var heroIntercept;

var HERO_SPEED = 2;

​

const DEBUG = 1;

const ratio = 1 / 2; // ratio of hero to target speed

​

var dtt = 0.55;

var dttt = 0.55;

var dth = 0.55;

​

function setup() {

  createCanvas(400, 400);

​

  target = createVector(200, 50);

  targetsTarget = createVector(-50, 100);

  hero = createVector(200, 300);

​

  heroIntercept = createVector(hero.x, hero.y); // just aim at yourself first.

}

​

function drawStuff() {

  // the target

  circle(target.x, target.y, 5);

  if (DEBUG) {

    point(targetsTarget.x, targetsTarget.y);

  }

​

  // the hero

  circle(hero.x, hero.y, 7);

}

​

function updateStuff() {

  // update hero;

  hero.x += dth;

  if (hero.x < 50 || hero.x > 350) {

    dth = -dth;

  }

​

  // update the potential intercept of the hero with binary search

  heroIntercept = findIntercept(hero, target, targetsTarget);

​

  // update target;

  target.x -= dtt * ratio;

  if (target.x < 50 || target.x > 350) {

    dtt = -dtt;

  }

​

  // update the targets target;

  // this is easier and more like the thing im trying to mimic

  // than rotating the targets speed vector or something.

​

  targetsTarget.x -= dttt / ratio;

  if (targetsTarget.x < -50 || targetsTarget.x > 450) {

    dttt = -dttt;

  }

}

​

// function bestIntercept(hero, target, targetsTarget) {

//   var targetVector = p5.Vector.sub(targetsTarget, target);

​

//   for (var turn = 1; turn < 200; turn++) {

//     var targetMovement = targetVector.copy().setMag(turn * TARGET_SPEED);

//     var target_pos = p5.Vector.add(target, targetMovement);

//     // total distance to travel minus the distance we can already travel during these turns

//     var turns_to_travel = (hero.dist(target_pos) - (HERO_SPEED * turn)) / HERO_SPEED;

//     // target moved whilst we traveled

//     targetMovement.setMag(turns_to_travel*TARGET_SPEED)

//     var new_target_pos = p5.Vector.add(target_pos, targetMovement)

//     var catchup_distance = target_pos.dist(new_target_pos);

//     var time_to_catchup  = (catchup_distance/HERO_SPEED) +

//   }

// }

function vline(v1, v2) {

  line(v1.x, v1.y, v2.x, v2.y);

}

​

function findIntercept(hero, target, targetsTarget) {

  var target_heading = p5.Vector.sub(targetsTarget, target);

  target_heading.setMag(TARGET_SPEED);

​

  // var [x0, y0] = [target.x+(target_heading.x*-1000),target.y+(target_heading.y*-1000)]

  // var [x1, y1] = [target.x+(target_heading.x*1000),target.y+(target_heading.y*1000)]

  var fb = p5.Vector.add(target, p5.Vector.mult(target_heading, -1000));

  var ff = p5.Vector.add(target, p5.Vector.mult(target_heading, 1000));

​

  // target movement line

  push();

  stroke(0, 100, 0, 25);

  vline(ff, fb);

  pop();

​

  var next_pos = p5.Vector.add(target, target_heading);

  // next pos is so close to actual pos, it isnt visible like this

  // circle(next_pos.x, next_pos.y, 2)

​

  var eta = hero.dist(next_pos) / HERO_SPEED;

​

  target_heading.setMag(eta * TARGET_SPEED);

  var actual_pos = p5.Vector.add(target, target_heading);

​

  var extra_distance = next_pos.dist(actual_pos);

  var extra_time = extra_distance / HERO_SPEED;

​

  // show where the target would be

  push();

  stroke(255, 0, 0, 25);

  vline(hero, target);

  stroke(255, 0, 0, 50);

  vline(actual_pos, target);

  translate(actual_pos.x, actual_pos.y);

  line(-2, 2, 2, -2);

  line(-2, -2, 2, 2);

  pop();

​

  var best_time = 100000;

  var best;

  for (var i = 1; i < 250; i += 10) {

    i += 1;

    target_heading.setMag(TARGET_SPEED * i);

​

    const hero_target = p5.Vector.add(target, target_heading);

    const time = (hero.dist(hero_target) - HERO_SPEED * i) / HERO_SPEED;

​

    // target moves whilst hero spends time to get to the target

    target_heading.setMag(time * TARGET_SPEED);

​

    // new pos = prev pos + movement whilst hero was walking

    const actual_pos = p5.Vector.add(hero_target, target_heading);

    const extra_distance = hero_target.dist(actual_pos);

    const extra_time = (extra_distance * 2) / HERO_SPEED;

​

    if (time + extra_time < best_time) {

      push();

      rectMode(CENTER);

      translate(hero_target.x, hero_target.y);

      rect(0, 0, 2, 2);

      pop();

      best = hero_target;

    }

    best_time = min(best_time, time + extra_time);

  }

​

  print(`${best_time} was the best time`);

​

  push();

  rectMode(CENTER);

  translate(best.x, best.y);

  rect(0, 0, 5, 5);

  pop();

}

​

//   target_heading.setMag(TARGET_SPEED*eta)

//   hero_target.add(target_heading)

​

//   vline(hero_target, hero);

​

//   push()

//   translate(hero_target.x, hero_target.y);

​

//   line(-2,2,2,-2);

//   line(-2,-2,2,2);

//   pop();

​

function draw() {

  background(220);

​

  updateStuff();

  drawStuff();

}

​