How to draw "Draw Arc Ticks".

IknowQT

void wCtrl_Indicator::paintEvent(QPaintEvent* e)
{

	QPainter		painter(this);
	
	drawBackGround(&painter);
	drawTicks(&painter);
}

void wCtrl_Indicator::drawTicks(QPainter* painter)
{
	QRect		drawingRect(this->rect());
	//drawingRect.adjusted(15, 15, -20, -20);

	QBrush		brushActive(Qt::red);
	QPen		pen(QBrush(brushActive), 2);
	pen.setCapStyle(Qt::FlatCap);

	painter->setPen(pen);
	painter->setBrush(brushActive);
	painter->setRenderHints(QPainter::Antialiasing | QPainter::SmoothPixmapTransform);
	
	qreal dStartAngle	= 225;
	qreal dEndAngle		= -45;
	painter->rotate(-dStartAngle);

	qreal dAngleStep = (-dEndAngle + dStartAngle) / m_nStep;
	for (int i = 0; i < m_nStep; i++)
	{
		//painter->drawLine((drawingRect.center().x(), drawingRect.center().y());
		painter->drawLine(30, 0, 40, 0);
		painter->rotate(dAngleStep);
	}
}

void wCtrl_Indicator::drawBackGround(QPainter* painter)
{
	QRect		drawingRect(0, 0, this->size().height(), this->size().height());
	QBrush		brushBackgnd(QColor(63, 67, 70));
	QPen		pen(QBrush(brushBackgnd), 10);
	pen.setCapStyle(Qt::FlatCap);

	painter->setPen(pen);
	painter->setBrush(brushBackgnd);
	painter->setRenderHints(QPainter::Antialiasing | QPainter::SmoothPixmapTransform);
	painter->drawArc(drawingRect.adjusted(15, 15, -20, -20), 90 * 16, ConvertAngle(m_nMax) * 16);
}

I want to draw Tick, how can I approach it?

mpergand

painter.drawEllipse(rect().center(),20,20);

Put this line before any translation.

IknowQT

How do I calculate the position?

mpergand

  QPoint c=rect().center();
        painter.translate(c);
        painter.rotate(-225);
        float step=20;
        
        for(int s=0;s<=step;s++)
            {
            painter.drawLine(30,0,40,0);
            painter.rotate(270/step);
            }
        
        float val=50; 
        float maxVal=100;    // range 0-100
        painter.resetTransform();
        painter.translate(c);
        painter.rotate(-225);
        painter.rotate(270*val/maxVal);
        painter.drawLine(00,0,40,0);

[EDIT] better code and adding current value position

IknowQT

@mpergand

When drawing an oval progress, it seems to be a problem due to increasing the pen thickness and changing the drawing right (adjusted), but can you automatically adjust the center even if the thickness is increased?

mpergand

@IknowQT said in How to draw "Draw Arc Ticks".:

When drawing an oval progress, it seems to be a problem due to increasing the pen thickness and changing the drawing right (adjusted), but can you automatically adjust the center even if the thickness is increased?

Sorry I don't understand what you want to do.

IknowQT

@mpergand

I'm not good at English, so please understand

I want to move the ellipse to the center

============================================

Add
The move to the center was successful, but why is the ellipse cut off to the sides?

void wCtrl_Indicator::drawBackGround(QPainter* painter)
{
	//QRect		drawingRect(this->rect());
	QPoint		p = this->rect().center();
	QRect drawingRect(1, 1, this->size().width(), this->size().height());
	QBrush		brushBackgnd(QColor(63, 67, 70));
	QPen		pen(QBrush(brushBackgnd), 10);
	pen.setCapStyle(Qt::FlatCap);

	painter->setPen(pen);
	painter->setBrush(brushBackgnd);
	painter->setRenderHints(QPainter::Antialiasing | QPainter::SmoothPixmapTransform);
	painter->drawArc(drawingRect, 90 * 16, ConvertAngle(m_nMax) * 16);
	/*painter->drawArc(drawingRect.center().x(), drawingRect.center().y(), this->size().width(), this->size().height(),
		90 * 16, ConvertAngle(m_nMax) * 16);*/
}

I think there's a problem with drawing right.