mousPressEvent off position when drawing on scene

Richter9.7

I'm trying to draw points on a scene but the points are drawn off position.


#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QGraphicsView>
#include <QGraphicsScene>
#include <QGraphicsEllipseItem>
#include <QMouseEvent>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();
    void mousePressEvent(QMouseEvent *e);

private:
    Ui::MainWindow *ui;
    QGraphicsScene *scene;
};

#endif // MAINWINDOW_H

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QGraphicsScene>
#include <QPointF>

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    scene = new QGraphicsScene();

    ui->graphicsView->setScene(scene);
}


MainWindow::~MainWindow()
{
    delete ui;
}

void MainWindow::mousePressEvent(QMouseEvent *e)
{

    double rad = 2;
    QPointF pt = ui->graphicsView->mapToScene(e->pos());
    scene->addEllipse(pt.x()-rad, pt.y()-rad, rad*2.0, rad*2.0, QPen(), QBrush(Qt::SolidPattern));
}

Any thoughts?
Thanks in advance!

SGaist

Hi and welcome to devnet,

You are mapping to the scene a point that is valid in your MainWindow not in your QGraphicsView

Richter9.7

Thank you for your reply!
This was simple and useful. Problem solved!