Thanks, solution found, similar to what you are suggesting.
I dug a bit further into Qt docs and found the entry for setPointsConfiguration, which takes data in the form of
QHash<int, QHash<QXYSeries::PointConfiguration, QVariant>>
So my new code for setting the colors looks like:
QHash<int, QHash<QXYSeries::PointConfiguration, QVariant>> ptsConfig;
QList<BrthPosnPlots>::iterator brthItr = m_brthPosns.begin();
MultiLineSeries *thisSrs = GetLineSeries(srs);
QList<QPointF> srspts = thisSrs->points();
quint32 ctSrs = srspts.size();
if ((ctSrs < 1))
return;
qsizetype bpos;
for (brthItr = m_brthPosns.begin(); brthItr != m_brthPosns.end(); brthItr++) {
if ((*brthItr).GetEEPos() > ctSrs)
continue;
if (((*brthItr).GetEIPos() > 1) && ((*brthItr).GetEEPos() > (*brthItr).GetEIPos() + 5)) {
for (bpos = (*brthItr).GetEIPos(); bpos < (*brthItr).GetEEPos(); bpos++) {
ptsConfig.insert_or_assign(bpos, conf);
// thisSrs->setPointConfiguration(bpos, conf);
}
}
}
if (!ptsConfig.isEmpty()) {
thisSrs->setPointsConfiguration(ptsConfig);
}
The speedup is truly amazing! From over 2 sec down to < 20 msec for this method.
Thanks to all for feedback and tips.
