Constant velocity problem for variable length Text Animation?

Dear Everyone!

I am animating text using QTimeline & QGraphicsItem Class. I am facing problem of varing velocity (speed of text) of text if text size is not equal for multiple animation. I want to constant velocity (animation speed constant) for variable length text. What can I do for this.

I am putting the code for that....

Code:

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QGraphicsTextItem *scrItem = new QGraphicsTextItem(txtScrollEdit->toPlainText());
	QDir::setCurrent(QDir::currentPath ()+"/media");
	QGraphicsScene *scene=new QGraphicsScene();
 
	scrItem->setDefaultTextColor(Qt::red);
	scene->setBackgroundBrush(Qt::yellow);
 
 
	QGraphicsItemAnimation *animation = new QGraphicsItemAnimation;
 
    animation->setItem(scrItem);
 
 
	float n;
	view=new QGraphicsView(scene,btgScrollText);
	view->setWindowFlags (Qt::FramelessWindowHint);
 
	scene->addItem(scrItem);
 
	view->setVerticalScrollBarPolicy( Qt::ScrollBarAlwaysOff );
	view->setHorizontalScrollBarPolicy( Qt::ScrollBarAlwaysOff );
	view->setCacheMode(QGraphicsView::CacheBackground);
 
	n=355;	/*Width of txtScrollEdit TextEdit*/
 
	qreal h=scene->height()/2-scrItem->boundingRect().height()/2;
 
 
    register int velocity=40;
	register int tl=n*velocity;
 
	timer = new QTimeLine(tl);
 
 
	timer->setCurveShape(QTimeLine::LinearCurve);
	timer->setLoopCount(0);
	animation->setTimeLine(timer);
	animation1->setTimeLine(timer);
 
 
	register int scrItembrw=scrItem->boundingRect().width();
	for (register int i=0; i<(n+scrItembrw); i=i+1)
	{
		register QPointF p(0,h); //sets the position of scrItem
		p.setX(n-i);
		p.setY(h);
		animation->setPosAt(i/(n+scrItembrw),p);
 
	 }//end for
 
	view->show();
	timer->start();

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Thanks in Advance!

Your problem is that your animation "frames" number is a function of the text size.
You should have that as a constant, if you want the same speed effect.

Code:

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register int scrItembrw=scrItem->boundingRect().width();
for (register int i=0; i<(n+scrItembrw) /*this should be a constant*/; i=i+1)
    {
        register QPointF p(0,h); //sets the position of scrItem
        p.setX(n-i);
        p.setY(h);
        animation->setPosAt(i/(n+scrItembrw),p);
 
     }//end for

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