tao-test/app/taoQtiItem/views/js/portableLib/OAT/interact-rotate.js

104 lines
3.4 KiB
JavaScript

define([
'taoQtiItem/portableLib/jquery_2_1_1',
'taoQtiItem/portableLib/interact',
'taoQtiItem/portableLib/OAT/sts/transform-helper'
], function(
$,
interact,
transformHelper
){
'use strict';
/**
* Start rotation, this will work on on mobile and desktop
* Note: this will work on ONE rotatable only!
*
* @param rotatable single DOM element
* @param handleSelector
*/
function init (rotatable, handleSelector) {
var handles,
angle = 0,
origin,
fn = (!!interact.supportsTouch() ? 'gesturable' : 'draggable'),
i;
handles = handleSelector ? rotatable.querySelectorAll(handleSelector) : [rotatable];
origin = transformHelper.getRotationCenter(rotatable);
i = handles.length;
while(i--) {
interact(handles[i])[fn]({
onmove: function (event) {
var handleAngle, offset, hypotenuse, transformObject,
currentAngle, R, S, RS, sides, absPosition, vectors,
vector, length;
handleAngle = event.target.className.indexOf('sts-handle-rotate-l') > -1
? -90
: 90;
offset = $(rotatable).offset();
// This section calculates the absolute position of the centre of the shape.
// TODO: take account of the larger square
// origin x and y are here the sides of the triangle
hypotenuse = Math.sqrt((origin.x * origin.x) + (origin.y * origin.y));
// get currently applied angle
transformObject = transformHelper.cssTransformObj(rotatable);
currentAngle = parseInt(transformObject.rotate, 10);
// angles
// R requires us to get the real rotation, not the applied rotation that is based
// on the rotation helpers
R = (currentAngle - handleAngle) * (Math.PI / 180);
S = Math.atan2(origin.x, origin.y) - (Math.PI / 2.0);
RS = R + S;
// new sides
sides = {
b: Math.abs(Math.sin(RS) * hypotenuse),
c: Math.abs(Math.cos(RS) * hypotenuse)
};
absPosition = {
x: sides.b + offset.left,
y: sides.c + offset.top
};
// Using the absolute position, turn towards the mouse position
vectors = {
x: absPosition.x - event.clientX,
y: -(absPosition.y - event.clientY)
};
length = Math.sqrt((vectors.x * vectors.x) + (vectors.y * vectors.y));
for(vector in vectors) {
vectors[vector] /= length;
}
angle = Math.atan2(vectors.x, vectors.y) * (180 / Math.PI);
// The rotation helper's angle to the real rotation needs to be taken into account
angle += handleAngle;
rotatable.style.webkitTransform = rotatable.style.transform = 'rotate(' + (angle).toString() + 'deg)';
}
});
}
}
return {
init: init
}
});