RitaDias

if ((translateX < (-menuWidth) / 2) || (Math.abs(translateX) / timeTaken > velocity)) { 
  // if menu is open, this represents the close condition
               

if (translateX > menuWidth / 2 || (Math.abs(translateX) / timeTaken > velocity)) { 
  // if menu is closed, this represents the open condition

RitaDias

if (translateX === 0 && translateY === 0) {
  if (isOpen) {
    appMenu.classList.remove("no-transition");
    menu.classList.remove("no-transition");
  } else {
    menu.classList.remove("menu--background-visible");
    menu.classList.remove("no-transition");
  }
}

RitaDias

function touchEnd(currentX, currentY, translateX, translateY, timeTaken) {
  isMoving = false;
  var velocity = 0.3;
  //... 
}

RitaDias

var newOpacity = (((maxOpacity) * percentage) / 100);

RitaDias

overlay.classList.add("no-transition");

var percentageBeforeDif = (Math.abs(moveX) * 100) / menuWidth;
var percentage = 100 - percentageBeforeDif;

RitaDias

function updateUi() {
  if (isMoving) {
    var element = document.querySelector(".app-menu-container");

    element.style.transform = "translateX(" + moveX + "px)";
    element.style.webkitTransform = "translateX(" + moveX + "px)";

    requestAnimationFrame(updateUi);
  }
}

RitaDias

moveX + (currentX - lastX)

RitaDias

if (moveX + (currentX - lastX) < 0 && moveX + (currentX - lastX) > -menuWidth) {
  moveX = moveX + (currentX - lastX);
  // ...
}

RitaDias

if (dragDirection === "vertical") {
  lastX = currentX;
  lastY = currentY;
} else {
  evt.preventDefault(); 
  // ...
}

RitaDias

function touchMove(evt, currentX, currentY, translateX, translateY) {
  if (!dragDirection) {
    if (Math.abs(translateX) >= Math.abs(translateY)) {
      dragDirection = "horizontal";
    } else {
      dragDirection = "vertical";
    }

    requestAnimationFrame(updateUi); 
    // this is what actually does the animation (ﾉ◕ヮ◕)ﾉ*:・ﾟ✧