javascript - 模态内的Fabricjs画布导致鼠标坐标偏移

Question

我是Fabric.js库的新手。我的鼠标坐标有问题。我想克隆模态内的标记，但坐标不正确。我制作了这个jsfiddle示例，您将在其中更好地了解发生了什么。

这是我的代码：

<!-- Button trigger modal -->
<button type="button" class="btn btn-primary btn-lg" data-toggle="modal" data-target="#myModal">
  Launch demo modal
</button>

<!-- Modal -->
<div class="modal fade" id="myModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true">
  <div class="modal-dialog">
    <div class="modal-content">
      <div class="modal-header">
        <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span></button>
        <h4 class="modal-title" id="myModalLabel">Modal title</h4>
      </div>
      <div class="modal-body">
        <canvas id="c" height="600" width="632"></canvas>
      </div>
      <div class="modal-footer">
        <button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
        <button type="button" class="btn btn-primary">Save changes</button>
      </div>
    </div>
  </div>
</div>

JavaScript：

var canvas = new fabric.Canvas('c');


$('#myModal').on('show.bs.modal', function (e) {

    // Ugly! Wish there was a better way than waiting for the modal to load!
    setTimeout(function(){
        canvas.calcOffset();
    }, 1000);
    
});


var mousecursor = new fabric.Circle({ 
  left: 0, 
  top: 0, 
  radius: 5, 
  fill: '#9f9', 
  originX: 'right', 
  originY: 'bottom',
})

canvas.add(mousecursor);

canvas.on('mouse:move', function(obj) {
  mousecursor.top = obj.e.y - mousecursor.radius;
  mousecursor.left = obj.e.x - mousecursor.radius;
  canvas.renderAll()
})

canvas.on('mouse:out', function(obj) {
  // put circle off screen
  mousecursor.top = -100;
  mousecursor.left = -100;
  canvas.renderAll()
})

canvas.on('mouse:up', function(obj) {
  canvas.add(mousecursor.clone())
  canvas.renderAll()
})

标签： javascriptmouseeventfabricjs