Issues with mapping with QTransform

[pkohut]

Is the pixmap a scene item too?

[spawn9997]

Is the pixmap a scene item too?

The way it is setup, the QGraphicsItem displays the 'correct' pixmap depending on level of detail. Part of the function of 'MyGraphicsItem' is to initially draw itself onto a pixmap and then use the painter function QPainter::drawPixmap() in the QGraphicsItem::paint() function.

Btw, using Qt 4.6.2.

[pkohut]

Can you calc the mid point of the source and then setPos on the pixmapItem?

Totally not tested (or compiled), but looks correct

QVector2d vTopLeft(rect.topLeft());
QVector2d vMid = vTopLeft + ((QVector(rect.bottomRight()) - vTopLeft) * 0.5);
pixmap->setPos(vMid->toPointF());

QVector2d vTopLeft(rect.topLeft());
QVector2d vMid = vTopLeft + ((QVector(rect.bottomRight()) - vTopLeft) * 0.5);
pixmap->setPos(vMid->toPointF());

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[spawn9997]

@pkohut I actually figured it out before I looked at this. I basically did exactly what you suggested. I forgot to set the new scaled Rectangle's center to the old Rectangle's center. The scaled rectangle is used to map points to the pixmap. I was mapping to a rectangle at the wrong position, Doh! When I called

QRectF tmp(x,y,w,h);
tmp.moveCenter(m_realRect.center());

QRectF tmp(x,y,w,h);
tmp.moveCenter(m_realRect.center());

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and then mapped the points to this rectangle, everything looked exactly as it was supposed to.

[pkohut]

QRectF tmp(x,y,w,h);
tmp.moveCenter(m_realRect.center());

QRectF tmp(x,y,w,h);
tmp.moveCenter(m_realRect.center());

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Ha, scanned right past center and moveCenter, was looking for middle.