83 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			83 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
import * as eventUtil from './event.js';
 | 
						|
var GestureMgr = (function () {
 | 
						|
    function GestureMgr() {
 | 
						|
        this._track = [];
 | 
						|
    }
 | 
						|
    GestureMgr.prototype.recognize = function (event, target, root) {
 | 
						|
        this._doTrack(event, target, root);
 | 
						|
        return this._recognize(event);
 | 
						|
    };
 | 
						|
    GestureMgr.prototype.clear = function () {
 | 
						|
        this._track.length = 0;
 | 
						|
        return this;
 | 
						|
    };
 | 
						|
    GestureMgr.prototype._doTrack = function (event, target, root) {
 | 
						|
        var touches = event.touches;
 | 
						|
        if (!touches) {
 | 
						|
            return;
 | 
						|
        }
 | 
						|
        var trackItem = {
 | 
						|
            points: [],
 | 
						|
            touches: [],
 | 
						|
            target: target,
 | 
						|
            event: event
 | 
						|
        };
 | 
						|
        for (var i = 0, len = touches.length; i < len; i++) {
 | 
						|
            var touch = touches[i];
 | 
						|
            var pos = eventUtil.clientToLocal(root, touch, {});
 | 
						|
            trackItem.points.push([pos.zrX, pos.zrY]);
 | 
						|
            trackItem.touches.push(touch);
 | 
						|
        }
 | 
						|
        this._track.push(trackItem);
 | 
						|
    };
 | 
						|
    GestureMgr.prototype._recognize = function (event) {
 | 
						|
        for (var eventName in recognizers) {
 | 
						|
            if (recognizers.hasOwnProperty(eventName)) {
 | 
						|
                var gestureInfo = recognizers[eventName](this._track, event);
 | 
						|
                if (gestureInfo) {
 | 
						|
                    return gestureInfo;
 | 
						|
                }
 | 
						|
            }
 | 
						|
        }
 | 
						|
    };
 | 
						|
    return GestureMgr;
 | 
						|
}());
 | 
						|
export { GestureMgr };
 | 
						|
function dist(pointPair) {
 | 
						|
    var dx = pointPair[1][0] - pointPair[0][0];
 | 
						|
    var dy = pointPair[1][1] - pointPair[0][1];
 | 
						|
    return Math.sqrt(dx * dx + dy * dy);
 | 
						|
}
 | 
						|
function center(pointPair) {
 | 
						|
    return [
 | 
						|
        (pointPair[0][0] + pointPair[1][0]) / 2,
 | 
						|
        (pointPair[0][1] + pointPair[1][1]) / 2
 | 
						|
    ];
 | 
						|
}
 | 
						|
var recognizers = {
 | 
						|
    pinch: function (tracks, event) {
 | 
						|
        var trackLen = tracks.length;
 | 
						|
        if (!trackLen) {
 | 
						|
            return;
 | 
						|
        }
 | 
						|
        var pinchEnd = (tracks[trackLen - 1] || {}).points;
 | 
						|
        var pinchPre = (tracks[trackLen - 2] || {}).points || pinchEnd;
 | 
						|
        if (pinchPre
 | 
						|
            && pinchPre.length > 1
 | 
						|
            && pinchEnd
 | 
						|
            && pinchEnd.length > 1) {
 | 
						|
            var pinchScale = dist(pinchEnd) / dist(pinchPre);
 | 
						|
            !isFinite(pinchScale) && (pinchScale = 1);
 | 
						|
            event.pinchScale = pinchScale;
 | 
						|
            var pinchCenter = center(pinchEnd);
 | 
						|
            event.pinchX = pinchCenter[0];
 | 
						|
            event.pinchY = pinchCenter[1];
 | 
						|
            return {
 | 
						|
                type: 'pinch',
 | 
						|
                target: tracks[0].target,
 | 
						|
                event: event
 | 
						|
            };
 | 
						|
        }
 | 
						|
    }
 | 
						|
};
 |