Question

这是我的代码要点。

Leap.loop({enableGestures: true}, function(frame) {
var gestures = frame.gestures;

for (var i = 0; i < gestures.length; i++) { 
  // I want to do something when draw circle with one pointable 
   if (gesture.type == "circle" && gesture.state == "stop" && gesture.pointableIds.length == 1) {
    var isClockWise = ? ;//  how to know the direction of circle ?
  }
}
} );

如何通过手势对象知道圆圈顺时针还是逆时针？

我使用跳跃动作只有2天，真的需要你的帮助。

Answer 1

Leap.loop({enableGestures: true},function(frame) {
var gestures = frame.gestures,
    circle,
    pointable,
    direction,
    normal;
// Check if is there any gesture going on
if(gestures.length > 0) {
    // In this example we will focus only on the first gesture, for the sake of simplicity
    if(gestures[0].type == 'circle') {
        circle = gestures[0];
        // Get Pointable object
        circle.pointable = frame.pointable(circle.pointableIds[0]);
        // Reset circle gesture variables as nedded, not really necessary in this case
        if(circle.state == 'start') {
            clockwise = true;
        } else if (circle.state == 'update') {
            direction = circle.pointable.direction;
            // Check if pointable exists
            if(direction) {
                normal = circle.normal;
                // Check if product of vectors is going forwards or backwards
                // Since Leap uses a right hand rule system
                // forward is into the screen, while backwards is out of it
                clockwise = Leap.vec3.dot(direction, normal) > 0;
                if(clockwise) {
                    //Do clockwose stuff
                } else {
                    //Do counterclockwise stuff
                }
            }
        }
    }
}

}）;

Answer 2

查看在飞跃网站上给出的C ++示例，给出了一段代码来检测圆是顺时针的。

C ++代码：

if (circle.pointable().direction().angleTo(circle.normal()) <= PI/4)
   {
      clockwiseness = "clockwise";
   }
   else
   {
      clockwiseness = "counterclockwise";
   }

我没有使用过Javascript API，但我认为这可能是等价的此代码尚未经过测试，但在Javascript中可能类似于：

// considere your gesture is a circle, and there is at least one pointable object.
if (gesture.type == "circle" && gesture.state == "stop" && gesture.pointableIds.length >= 1)
{
  var dir = frame.pointables[gesture.pointableIds[0] ].direction; // get direction of the Pointable used for the circle gesture
  var angle = dir.AngleTo (circle.normal);
  var isClockWise =  angle <= (3.14 / 4);
}

从GitHub和Leap Motion Developers site

获取Leap JS API的所有信息

- ＆GT;小心frame.pointables以任意顺序返回指针对象。（Cf JS API doc）。这段代码仅用于解释算法

Answer 3

这是查找

的最简单方法

var isClockwise = (circleGesture.normal[2] <= 0);

它将返回true或false

Answer 4

在此页面上尝试了其他答案并且无法使其工作，简化了一些代码并最终使其正常工作。 pointableID根据圆形手势的方向记录正常为负/正。

function pageScrollDown() {
   window.scrollBy(0,10);
};
function pageScrollUp(){
   window.scrollBy(0,-15);
};

$(window).bind('circle', function(e, gesture){

var circle = gesture;

circle.pointable = circle.pointableIds[0];
direction = gesture.normal[1];

    if(direction < 0 ) {
      pageScrollDown();
      } else {
        pageScrollUp();
}
});

Answer 5

我一直在为我的项目使用“Leap Cursor库”，这真的很酷。使用此库可以非常简单地识别元素上的圆形手势。

var circleTrackElements = document.querySelectorAll(".myDOMElements");
for (var i = 0; i < allTiles.length; i++) {
    circleTrackElements[i].addEventListener("leap-circle-stop", function(e) {
        console.log("CIRCLE DETECTED");
    });
};
LeapManager.init({
    maxCursors : 1,
    interactiveSelector : ".myDOMElements"
});

GITHUB link for the library

如何检测圆圈手势方向？

5 个答案: