[help!] QGraphicsScene background image manipulation - adding the margin next to the background image

poorBob

Hello Qt deveopers :).

I have some problems regarding the QGraphicsScene image manipulation.

However, before describing my main problem I would like to ask You about different issue: some time ago I had registered here and today I wanted to log-in with that old account. I forgot my password so I followed the "password reseting" procedure, but it failed. I received an email with a new temporary pass but after typing it Qt-project web shown the login error... I reseted the password for 4 times but unsuccessfully... Do You know how to fix this?

Regarding my problem with the image: I have created the scene, view and some items placed on the scene. I set the background image with following way:

@
QString m_strBackgroundPath("/home/pic.jpg");
QImage oImage( m_strBackgroundPath );
m_pScene->setSceneRect( oImage.rect() );
m_pScene->setBackgroundBrush( oImage );
@

So far everything is fine: the picture is painted in the background, the items are painted/shown "on" this picture and everything is presented in the view.

But, sometimes, for certain items I would like to show a little information in the right side of the view. The information is shown in some-kind of information widget. The problem is that this information widget may overlap the item. In such case I would like to move the whole scene with all items to the left, so the focused item would be still visible. I figured out that in the right side of the scene I can add some margin and then "move" the view. I tried to extend the scene rectangle to the right with the following code:

@
QRectF myGraphicsScene::sceneRect() const
{
const QRectF oSceneRect = QGraphicsScene::sceneRect();
QRectF oAdjRect(oSceneRect);
oAdjRect.adjust(0,0,150,0);
qDebug() << "CPTGraphicsScene::sceneRect()" << oSceneRect << oAdjRect;
return oAdjRect;
}
@

and draw the margin this way:
@void myGraphicsScene::drawBackground(QPainter* pPainter, const QRectF& rRect)
{
QBrush oBrush = backgroundBrush();

QRectF oRect( rRect.x()-rRect.width(), rRect.y()
, 150, rRect.height() );
qDebug() << "CPTGraphicsScene::drawBackground!" << rRect << sceneRect() << oRect;

if ( oBrush.style() != Qt::NoBrush )
{
pPainter->save();
pPainter->setBrushOrigin(0, 0);
pPainter->fillRect(rRect, oBrush);
pPainter->fillRect( oRect, Qt::red );
pPainter->restore();
}
}//END drawBackground()@

Value "150" is just for tests here ;). Unfortunately this doesn't work... :(

Do You have any idea what I'm doing wrong...

I would be grateful for any hind and advice.

Robert :)

poorBob

Hello, hello again :). Do You have any idea?

poorBob

Bump, bump :(

poorBob

Any idea? Anybody?

raven-worx

the rRect parameter is the exposed rectangle in the scene. I believe you want the background image as the scene background, meaning it should scroll with the items?

try this:
@
void myGraphicsScene::drawBackground(QPainter* pPainter, const QRectF& rRect)
{
QBrush oBrush = backgroundBrush();
QRectF sceneRect = this->sceneRect();

 pPainter->save();
     pPainter->setClipRegion( QRegion( rRect.toRect() ) );   //just some optimization
     pPainter->fillRect( sceneRect, Qt::red );  //you may optimize this line
     pPainter->fillRect( sceneRect.translated(-150,0), oBrush );
 pPainter->restore();

}
@