The image is not covering the full background

[A.H.M. Mahfuzur Rahman]

I have implemented the drawBackground() funciton of QGraphicsScene to draw a background from a pixmap image. Here is what I have done:

void GraphicsScene::drawBackground(QPainter* painter, const QRectF &rect){

painter->drawPixmap( 0, 0,
renderBackground( sceneRect().size().toSize() , false ));

}

Here rendereBackground( QSize& Mapsize, true) returns a pixmap of size Mapsize and it is working correctly.

But, the background image is not covering the full background

What should be the problem??

Thank You
Mahfuz