blureffect.cpp Example File

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 #include "blureffect.h"

 #include <QDebug>

 BlurEffect::BlurEffect(QGraphicsItem *item)
     : QGraphicsBlurEffect()
     , m_baseLine(200), item(item)
 {
 }

 void BlurEffect::adjustForItem()
 {
     qreal y = m_baseLine - item->pos().y();
     qreal radius = qBound(qreal(0.0), y / 32, qreal(16.0));
     setBlurRadius(radius);
 }

 QRectF BlurEffect::boundingRect() const
 {
     const_cast<BlurEffect *>(this)->adjustForItem();
     return QGraphicsBlurEffect::boundingRect();
 }

 void BlurEffect::draw(QPainter *painter)
 {
     adjustForItem();
     QGraphicsBlurEffect::draw(painter);
 }