Function computeInputData

docs/app/js/sanddance-app.js:92873–92904

* extend the data with some usable properties like scale, rotate, velocity etc * @param {Object} manager * @param {Object} input

(manager, input)

 * @param {Object} manager
 * @param {Object} input
 */ function computeInputData(manager, input) {
        var session = manager.session;
        var pointers = input.pointers;
        var pointersLength = pointers.length;
        // store the first input to calculate the distance and direction
        if (!session.firstInput) session.firstInput = simpleCloneInputData(input);
        // to compute scale and rotation we need to store the multiple touches
        if (pointersLength > 1 && !session.firstMultiple) session.firstMultiple = simpleCloneInputData(input);
        else if (pointersLength === 1) session.firstMultiple = false;
        var firstInput = session.firstInput;
        var firstMultiple = session.firstMultiple;
        var offsetCenter = firstMultiple ? firstMultiple.center : firstInput.center;
        var center = input.center = getCenter(pointers);
        input.timeStamp = now();
        input.deltaTime = input.timeStamp - firstInput.timeStamp;
        input.angle = getAngle(offsetCenter, center);
        input.distance = getDistance(offsetCenter, center);
        computeDeltaXY(session, input);
        input.offsetDirection = getDirection(input.deltaX, input.deltaY);
        var overallVelocity = getVelocity(input.deltaTime, input.deltaX, input.deltaY);
        input.overallVelocityX = overallVelocity.x;
        input.overallVelocityY = overallVelocity.y;
        input.overallVelocity = abs(overallVelocity.x) > abs(overallVelocity.y) ? overallVelocity.x : overallVelocity.y;
        input.scale = firstMultiple ? getScale(firstMultiple.pointers, pointers) : 1;
        input.rotation = firstMultiple ? getRotation(firstMultiple.pointers, pointers) : 0;
        input.maxPointers = !session.prevInput ? input.pointers.length : input.pointers.length > session.prevInput.maxPointers ? input.pointers.length : session.prevInput.maxPointers;
        computeIntervalInputData(session, input);
        // find the correct target
        var target = manager.element;
        if (hasParent(input.srcEvent.target, target)) target = input.srcEvent.target;
        input.target = target;
    }
    function computeDeltaXY(session, input) {
        var center = input.center;
        var offset = session.offsetDelta || {};