[Okular-devel] Re: About 265002 (Unreachable code in okular/ui/pageview.cpp (related to drag scroll))

[Денис Песоцкий]

>> Ok, I'm here.
>> It can happen in 2 cases:
>> 1) Mouse is moved by more than (screen height)/2 vetically between
>> event loops. I did that with my thinkpoint and it drags not as
>> excepted if I move cursor fast.
> Hmm, this is unfortunate we really never though that could be possible, are
> you really able to reproduce this easily?
Yes i do. If I press my trackpoint firm enought, it happens.
I think, you can repdroduce it with mouse, if make high enought sensitivity.

>> 2) Cursor had wrapped somewhere in other place of code. If it wraps
>> here, it will do d->mouseGrabPos = mousePos; anyway. As I can see, it
>> can also wrap while zooming, but it can it happen in the same time it
>> is draggin?
> Yes, just drag drag the mouse to the bottom of the screen and continue
> dragging and see what happens.

I know :). Look at your code:

                    if ( mousePos.y() <= mouseContainer.top() + 4 &&
                         verticalScrollBar()->value() <
verticalScrollBar()->maximum() - 10 )
                    {
                        mousePos.setY( mouseContainer.bottom() - 5 );
                        QCursor::setPos( mousePos );
                    }
                    // wrap mouse from bottom to top
                    else if ( mousePos.y() >= mouseContainer.bottom() - 4 &&
                              verticalScrollBar()->value() > 10 )
                    {
                        mousePos.setY( mouseContainer.top() + 5 );
                        QCursor::setPos( mousePos );
                    }
                    // remember last position
                    d->mouseGrabPos = mousePos;

It remembers new mouse position anyways. Ever if it wrapped,
mouseGrabPos corresponds to it. That's why there is no need to check
if it wrapped last time.

Now you understand me?