标记绘图的事件

// 示例代码：使用节流函数优化mousemove事件
function throttle(func, limit) {
  let inThrottle;
  return function() {
    const args = arguments;
    const context = this;
    if (!inThrottle) {
      func.apply(context, args);
      inThrottle = true;
      setTimeout(() => inThrottle = false, limit);
    }
  };
}

const handleMouseMove = throttle((event) => {
  // 处理绘图逻辑
}, 100);

canvas.addEventListener('mousemove', handleMouseMove);

// 示例代码：正确绑定事件监听器
canvas.addEventListener('mousedown', (event) => {
  // 处理mousedown事件
});

canvas.addEventListener('mousemove', (event) => {
  // 处理mousemove事件
});

canvas.addEventListener('mouseup', (event) => {
  // 处理mouseup事件
});

// 示例代码：获取准确的绘图坐标
canvas.addEventListener('mousemove', (event) => {
  const rect = canvas.getBoundingClientRect();
  const x = event.clientX - rect.left;
  const y = event.clientY - rect.top;
  // 使用x和y进行绘图
});