QCustomPlot 绘制卡顿问题-Toy模板网

这篇具有很好参考价值的文章主要介绍了QCustomPlot 绘制卡顿问题。希望对大家有所帮助。如果存在错误或未考虑完全的地方，请大家不吝赐教，您也可以点击"举报违法"按钮提交疑问。

大数据量导致曲线绘制卡顿问题
这里提供一个思路在跟踪源码中发现底层卡顿在vector的resize() 此处扩容中

所以尽量使用下面的接口

/*! \overload
  
  Adds the provided data point as \a key and \a value to the current data.
  
  Alternatively, you can also access and modify the data directly via the \ref data method, which
  returns a pointer to the internal data container.
*/
void QCPGraph::addData(double key, double value)
{
  mDataContainer->add(QCPGraphData(key, value));
}

而不是使用addData这个接口，还有setData这个接口文章来源地址https://www.toymoban.com/news/detail-682667.html

/*! \overload
  
  Adds the provided points in \a keys and \a values to the current data. The provided vectors
  should have equal length. Else, the number of added points will be the size of the smallest
  vector.
  
  If you can guarantee that the passed data points are sorted by \a keys in ascending order, you
  can set \a alreadySorted to true, to improve performance by saving a sorting run.
  
  Alternatively, you can also access and modify the data directly via the \ref data method, which
  returns a pointer to the internal data container.
*/
void QCPGraph::addData(const QVector<double> &keys, const QVector<double> &values, bool alreadySorted)
{
  if (keys.size() != values.size())
    qDebug() << Q_FUNC_INFO << "keys and values have different sizes:" << keys.size() << values.size();
  const int n = qMin(keys.size(), values.size());
  QVector<QCPGraphData> tempData(n);
  QVector<QCPGraphData>::iterator it = tempData.begin();
  const QVector<QCPGraphData>::iterator itEnd = tempData.end();
  int i = 0;
  while (it != itEnd)
  {
    it->key = keys[i];
    it->value = values[i];
    ++it;
    ++i;
  }
  mDataContainer->add(tempData, alreadySorted); // don't modify tempData beyond this to prevent copy on write
}