Jquery-旋转光标角度

我需要旋转箭头与Jquery旋转，但我不知道光标的角度:(我尝试计算它，但脚本不起作用。

我想要这样的结果http://www.lonhosford.com/content/html5/canvas/rotate_to_mouse.html

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Answer 1

如果你查看你发布的例子的源代码，你会发现

 update: function() { // Distance from mouse x and center of canvas. this._dx = mouse.x - this.centerX; // Distance from mouse y and center of canvas. this._dy = mouse.y - this.centerY; // Radians for the canvas rotate method. this._radians = Math.atan2(this._dy,this._dx); } 

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要根据自己的需要调整此代码，请尝试

 function diff(x, y) { var centerItem = $('imageid'), centerLoc = centeItem.offset(); var dx = x - centerLoc.left + (centerItem.width() / 2); dy = y - centerLoc.top + (centerItem.height() / 2); return Math.atan2(dy, dx) * (180 / Math.PI); } 

例子在http://jsfiddle.net/gaby/xWtKc/1/