#include "Widget.h"
#include <QPainter>
#include <QPainterPath>
#include <QRectF>

void Widget::paintEvent(QPaintEvent* /*event*/)
{
	// create objects to draw
	constexpr qreal size = 2e-12; // play with this
	QRectF rect(0, 0, size, size);
	QPainterPath path;
	path.addEllipse(rect);

	// set up painter
	QPainter painter(this);
	painter.setRenderHint(QPainter::Antialiasing);
	painter.setPen(QPen(Qt::black, 0));
	painter.scale(width() / size, height() / size);

	// draw objects
	painter.drawEllipse(rect); // this is ok
	painter.drawPath(path); // this fails for small sizes
}