Keep Cursor in a widget

[TheClerk]

Thanks for your answers so far. This is basicly what i tried before. Your example works fine for me and I agree with you that one could solve the issue of fast mouse moving with a timer. But if I try to implement this in my program it does not work. I had a look at the debugger and i think my geometry does not work properly. And I think this might be because i did something wrong with the derivation of my classes.

Would it help if I post my whole code here or what informations are required to help me with this issue?

Edit:
I have the problem that the upper and the left margin are ca. as twice as big as the lower and the right margin. Anyone has an idea why this is the case?

void MapView::mouseMoveEvent(QMouseEvent *event){
    int marginThickness = 30;
 
    int globalX = event->globalX();
    int globalY = event->globalY();
 
    int geoX = geometry().x();
    int geoY = geometry().y();
 
    QPoint globalGeo (this->mapToGlobal(QPoint(geoX, geoY)));
 
    QPoint newPos(globalX, globalY);
 
    if (globalY < globalGeo.y() + marginThickness){
        newPos.setY(globalGeo.y() + marginThickness);
    } else if (globalY > globalGeo.y() + height() - marginThickness){
        newPos.setY(globalGeo.y() + height() - marginThickness);
    }
    if (globalX < globalGeo.x() + marginThickness){
        newPos.setX(globalGeo.x() + marginThickness);
    } else if (globalX > globalGeo.x() + width() - marginThickness){
        newPos.setX(globalGeo.x() + width() - marginThickness);
    }
    this->cursor().setPos(newPos);
}

void MapView::mouseMoveEvent(QMouseEvent *event){
    int marginThickness = 30;

    int globalX = event->globalX();
    int globalY = event->globalY();

    int geoX = geometry().x();
    int geoY = geometry().y();

    QPoint globalGeo (this->mapToGlobal(QPoint(geoX, geoY)));

    QPoint newPos(globalX, globalY);

    if (globalY < globalGeo.y() + marginThickness){
        newPos.setY(globalGeo.y() + marginThickness);
    } else if (globalY > globalGeo.y() + height() - marginThickness){
        newPos.setY(globalGeo.y() + height() - marginThickness);
    }
    if (globalX < globalGeo.x() + marginThickness){
        newPos.setX(globalGeo.x() + marginThickness);
    } else if (globalX > globalGeo.x() + width() - marginThickness){
        newPos.setX(globalGeo.x() + width() - marginThickness);
    }
    this->cursor().setPos(newPos);
}

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[john_god]

Remove mapToGlobal from line 10, you dont need it sense geometry() is already global. Then check if it works

[TheClerk]

I am afraid this does not work. If I remove the mapToGlobal the following happens:

The area that can't be left by the Cursor stays in the top left corner of the screen. If i move the application a bit down and a bit right the boarder to the bottom and to the right become larger and i can leave the application to the top and the left of the frame because it won't get any mouseEvent then.

Edit:
If you want i can send you the whole code zipped. I think this makes things much easier.

[john_god]

Can you show me a printscreen of your game, and point the area where the cursor should be grabbed ?

[TheClerk]

Okay. Here we go:



This is how it looks at the moment. All things painted in red are included by me with photoshop and not part of the program. I want to keep the Cursor within the red rectangular. A and B indicate the width and the height of QGraphicsView. C and D show the actual Position of the Cursor in the QGraphicsView. This works correct so far. I just can't get the correct coordinates to set the Cursor when it is close the edge of the widget.

Thanks for your constant help by the way. I am sure we can manage this

Regards,
Simon

[TheClerk]

I figured it our myself now. Thanks for your help though.

Regards