The startangle value of drawArc is slightly off center.

[IknowQT]

void CustomIndicator::drawProgress(QPainter* painter)
{
	painter->save();
	{
		QPoint	center = this->rect().center();
		QRect	drawingRect(
			center.x() - m_nOffsetCenter,
			center.y() - m_nOffsetCenter,
			this->size().height() * 60 / 100,
			this->size().height() * 60 / 100);


		QBrush	brushBackgnd(m_ClrAnm);
		if (m_eStatus == CustomIndicator::INDICATOR_STATUS::ING)
		{
			brushBackgnd.setColor(m_ClrProgress);
			if (!m_pTimer->isActive())
				brushBackgnd.setColor(m_ClrBackground);
		}
		else
			brushBackgnd.setColor(m_ClrProgress);

		QPen	pen(QBrush(brushBackgnd), m_nThinkness);
		painter->setPen(pen);
		painter->setBrush(brushBackgnd);

		int nAngle = m_eStatus == CustomIndicator::INDICATOR_STATUS::ING || m_eStatus == CustomIndicator::INDICATOR_STATUS::STOP ? -45 * 16 : 360 * 16;

		if (m_eStatus == CustomIndicator::INDICATOR_STATUS::GENERAL)
			painter->drawArc(drawingRect, 90 * 16, m_rCurAngle * 16);
		else
			painter->drawArc(drawingRect, (m_rCurAngle--) * 16, nAngle);
	}
	
	painter->restore();
}

I set the startangle to 90 degrees and ran it.
The starting position is not in the center and there is some offset
What is wrong?

[mchinand]

Could be due to the pen's CapStyle. Try setting it to Qt::FlatCap.

[IknowQT]

@mchinand

I think you're right. thank you.