Fabric js stickman -以编程方式设置肢体动画，并维护所有圆和线之间的关节

// 创建Canvas对象
var canvas = new fabric.Canvas('canvas');

// 创建Stickman的各个部分
var head = new fabric.Circle({
  radius: 20,
  fill: 'yellow',
  left: 100,
  top: 100
});

var body = new fabric.Line([100, 120, 100, 200], {
  stroke: 'black',
  strokeWidth: 2
});

var leftArm = new fabric.Line([80, 140, 60, 160], {
  stroke: 'black',
  strokeWidth: 2
});

var rightArm = new fabric.Line([120, 140, 140, 160], {
  stroke: 'black',
  strokeWidth: 2
});

var leftLeg = new fabric.Line([100, 200, 80, 240], {
  stroke: 'black',
  strokeWidth: 2
});

var rightLeg = new fabric.Line([100, 200, 120, 240], {
  stroke: 'black',
  strokeWidth: 2
});

// 将Stickman的各个部分添加到Canvas中
canvas.add(head, body, leftArm, rightArm, leftLeg, rightLeg);

// 设置肢体动画
fabric.util.animate({
  startValue: 140,
  endValue: 100,
  duration: 1000,
  onChange: function(value) {
    leftArm.set({ y2: value });
    rightArm.set({ y2: value });
    canvas.renderAll();
  },
  onComplete: function() {
    // 动画完成后的回调函数
  }
});