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/*
* Vanilla JS - Touch Gestures
* @version 0.1
* @inspired QuoJS - http://quojs.tapquo.com
*
* Supported Gestures: singleTap, doubleTap, hold,
* swipe, swiping, swipeLeft, swipeRight, swipeUp, swipeDown,
* rotate, rotating, rotateLeft, rotateRight, pinch, pinching,
* pinchIn, pinchOut,
* drag, dragLeft, dragRight, dragUp, dragDown
*/
(function(window) {
"use strict";
var document = window.document,
CURRENT_TOUCH = [],
FIRST_TOUCH = [],
GESTURE = {},
HOLD_DELAY = 650,
TOUCH_TIMEOUT = 0;
/**
* Clear touch timeout
*
* @return void
*/
function clearTimer () {
if (TOUCH_TIMEOUT) {
clearTimeout(TOUCH_TIMEOUT);
}
}
/**
* @param {object} event Event object
* @return {Array.<object>}
*/
function getTouchesList (event) {
var e = event.originalEvent || event;
return e['touches'] || [e];
}
/**
* @param {Array} touches Touches list
* @param {number} fingers Count of fingers
* @return {Array.<{ x: {number}, y: {number} }>}
*/
function getFingerPosition (touches, fingers) {
var result = [],
i = 0;
touches = touches[0]['targetTouches'] ? touches[0]['targetTouches'] : touches;
while (i < fingers) {
result.push({
x: touches[i].pageX,
y: touches[i].pageY
});
i++;
}
return result;
}
/**
* @param {number} x1 Start "X" point
* @param {number} x2 End "X" point
* @param {number} y1 Start "Y" point
* @param {number} y2 End "Y" point
*/
function getSwipeDirection (x1, x2, y1, y2) {
if (Math.abs(x1 - x2) >= Math.abs(y1 - y2)) {
return (x1 - x2 > 0) ? 'Left' : 'Right';
} else {
return (y1 - y2 > 0) ? 'Up' : 'Down';
}
}
/**
* @param {Element} node
* @return {*}
*/
function getElementParentIfText (node) {
return ('tagName' in node) ? node : node['parentNode'];
}
/**
* Calculate rotation angle
*
* @param {Array} data
* @return {number}
*/
function calcAngle (data) {
var A = data[0],
B = data[1],
angle = Math.atan((B.y - A.y) * -1 / (B.x - A.x)) * (180 / Math.PI);
return (angle < 0) ? angle + 180 : angle;
}
/**
* Calculate fingers distance
*
* @param {Array} data
* @return {number}
*/
function calcDistance (data) {
var A = data[0],
B = data[1];
return Math.sqrt((B.x - A.x) * (B.x - A.x) + (B.y - A.y) * (B.y - A.y)) * -1;
}
/**
* @return void
*/
function clean () {
FIRST_TOUCH = [];
CURRENT_TOUCH = [];
GESTURE = {};
return clearTimer();
}
/**
* @param {string} name Event name
* @param {object?} props Event properties
* @return {*}
*/
function dispatch (name, props) {
if (GESTURE.el) {
var e = document.createEvent('Events');
e.initEvent(name, false, true);
if (!props) {
props = {};
}
if (CURRENT_TOUCH[0]) {
props.iniTouch = (GESTURE.fingers > 1 ? FIRST_TOUCH : FIRST_TOUCH[0]);
props.currentTouch = (GESTURE.fingers > 1 ? CURRENT_TOUCH : CURRENT_TOUCH[0]);
}
for (var param in props) {
if (props.hasOwnProperty(param)) {
e[param] = props[param];
}
}
return GESTURE.el.dispatchEvent(e);
}
}
/**
* @return void
*/
function hold () {
if (GESTURE.last && (Date.now() - GESTURE.last >= HOLD_DELAY)) {
dispatch('hold');
return clean();
}
}
/**
* @return {boolean}
*/
function gestureSwipe () {
var horizontal,
vertical;
if (CURRENT_TOUCH[0]) {
horizontal = Math.abs(FIRST_TOUCH[0].x - CURRENT_TOUCH[0].x) > 30;
vertical = Math.abs(FIRST_TOUCH[0].y - CURRENT_TOUCH[0].y) > 30;
return GESTURE.el && (horizontal || vertical);
}
return false;
}
/**
* @return {*}
*/
function gestureRotation () {
var angle = parseInt(calcAngle(CURRENT_TOUCH), 10),
diff = parseInt(GESTURE.initialAngle - angle, 10),
i,
symbol;
if (Math.abs(diff) > 20 || GESTURE.angleDifference !== 0) {
i = 0;
symbol = GESTURE.angleDifference < 0 ? '-' : '+';
while (Math.abs(diff - GESTURE.angleDifference) > 90 && i++ < 10) {
eval('diff ' + symbol + '= 180;');
}
GESTURE.angleDifference = parseInt(diff, 10);
return dispatch('rotating', {
angle: GESTURE.angleDifference
});
}
}
/**
* @return {*}
*/
function gesturePinch () {
var distance = parseInt(calcDistance(CURRENT_TOUCH), 10),
diff = GESTURE.initialDistance - distance;
if (Math.abs(diff) > 10) {
GESTURE.distanceDifference = diff;
return dispatch('pinching', {
distance: diff
});
}
}
/**
* Touch Start
*
* @param {object} event
* @return {*}
*/
function start(event) {
var now = Date.now(),
delta = now - (GESTURE.last || now),
fingers,
touches;
clearTimer();
touches = getTouchesList(event);
fingers = touches.length;
FIRST_TOUCH = getFingerPosition(touches, fingers);
GESTURE.el = getElementParentIfText(touches[0].target);
GESTURE.fingers = fingers;
GESTURE.last = now;
if (fingers === 1) {
GESTURE.isDoubleTap = delta > 0 && delta <= 250;
return setTimeout(hold, HOLD_DELAY);
} else if (fingers === 2) {
GESTURE.initialAngle = parseInt(calcAngle(FIRST_TOUCH), 10);
GESTURE.initialDistance = parseInt(calcDistance(FIRST_TOUCH), 10);
GESTURE.angleDifference = 0;
return GESTURE.distanceDifference = 0;
}
}
/**
* Touch Move
*
* @param {object} event
* @return {*}
*/
function move (event) {
if (GESTURE.el) {
var touches = getTouchesList(event),
fingers = touches.length;
if (fingers === GESTURE.fingers) {
CURRENT_TOUCH = getFingerPosition(touches, fingers);
if (gestureSwipe()) {
dispatch('swiping');
}
if (fingers === 2) {
gestureRotation();
gesturePinch();
event.preventDefault();
}
} else {
clean();
}
}
return true;
}
/**
* Touch End
*
* @return {*}
*/
function end () {
var direction;
if (GESTURE.fingers === 1) {
if (gestureSwipe()) {
dispatch('swipe');
direction = getSwipeDirection(FIRST_TOUCH[0].x, CURRENT_TOUCH[0].x, FIRST_TOUCH[0].y, CURRENT_TOUCH[0].y);
dispatch('swipe' + direction);
return clean();
} else {
if (GESTURE.isDoubleTap) {
dispatch('doubleTap');
return clean();
} else {
TOUCH_TIMEOUT = setTimeout(function () {
dispatch('singleTap');
clean();
}, 250);
return TOUCH_TIMEOUT;
}
}
} else if (GESTURE.fingers === 2) {
var anyEvent = false;
if (GESTURE.angleDifference !== 0) {
dispatch('rotate', {
angle: GESTURE.angleDifference
});
direction = 'rotate' + (GESTURE.angleDifference > 0 ? 'Right' : 'Left');
dispatch(direction, {
angle: GESTURE.angleDifference
});
anyEvent = true;
}
if (GESTURE.distanceDifference !== 0) {
dispatch('pinch', {
angle: GESTURE.distanceDifference
});
direction = 'pinch' + (GESTURE.distanceDifference > 0 ? 'Out' : 'In');
dispatch(direction, {
distance: GESTURE.distanceDifference
});
anyEvent = true;
}
if (!anyEvent && CURRENT_TOUCH[0]) {
if (Math.abs(FIRST_TOUCH[0].x - CURRENT_TOUCH[0].x) > 10 || Math.abs(FIRST_TOUCH[0].y - CURRENT_TOUCH[0].y) > 10) {
dispatch('drag');
direction = getSwipeDirection(FIRST_TOUCH[0].x, CURRENT_TOUCH[0].x, FIRST_TOUCH[0].y, CURRENT_TOUCH[0].y);
dispatch('drag' + direction);
}
}
return clean();
}
}
window.addEventListener('DOMContentLoaded', function () {
var listen = {
'touchstart' : start,
'touchmove' : move,
'touchend' : end,
'touchcancel' : clean };
for (var event in listen) {
if (listen.hasOwnProperty(event)) {
document.body.addEventListener(event, listen[event], false);
}
}
}, false);
}(window));
http://jsbin.com/ojufir/6
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