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Painting the mouse trace with QGraphicsItem

  • Hello,

    I have a QGraphicsView with a scene that displays an image. What I am trying to do now is when I click the mouse and move without un-clicking, I want to draw the mouse trace until the mouse button is released. So basically to draw with the mouse.

    Could someone please guide me to what I need to do for this?

    So far what I am trying to do is subclassing QGraphicsRectItem and from the mouse events of the QGV call my own functions in the GraphicsItem subclass passing as a parameter the QMouseEvent and handling things there.

    I know I have to implement the paint event to draw, but I'm a bit lost how to approach this. I was thinking maybe getting the points of the trace and drawing small line segments in between, would this be a good possible way?

    I appreciate any help. Thanks.

  • Did you take a look at the Finger Paint example?
    You only replace QTouchEvent with QMouseEvent.


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