Qt and keyboard events

So I’ve been messing around with integrating qt and urho. I have it set up to render frames with a qtimer (one frame at a time) and in my update event it won’t detect keyboard events. Mouse events work but it won’t detect any key presses. Is there something extra I have to do? My app is deriving from object and qapplication and has a run function which initializes engine.

1 Like

QWidget has virtual input event functions that can be overridden. A QMainWindow is a QWidget while a QApplication is not.
For example: You can use keyPressEvent(QKeyEvent* event) override to catch widget events.

From qwidget.h
    // Event handlers
    bool event(QEvent *event) Q_DECL_OVERRIDE;
    virtual void mousePressEvent(QMouseEvent *event);
    virtual void mouseReleaseEvent(QMouseEvent *event);
    virtual void mouseDoubleClickEvent(QMouseEvent *event);
    virtual void mouseMoveEvent(QMouseEvent *event);
#if QT_CONFIG(wheelevent)
    virtual void wheelEvent(QWheelEvent *event);
    virtual void keyPressEvent(QKeyEvent *event);
    virtual void keyReleaseEvent(QKeyEvent *event);
    virtual void focusInEvent(QFocusEvent *event);
    virtual void focusOutEvent(QFocusEvent *event);
    virtual void enterEvent(QEvent *event);
    virtual void leaveEvent(QEvent *event);
    virtual void paintEvent(QPaintEvent *event);
    virtual void moveEvent(QMoveEvent *event);
    virtual void resizeEvent(QResizeEvent *event);
    virtual void closeEvent(QCloseEvent *event);
    virtual void contextMenuEvent(QContextMenuEvent *event);
#if QT_CONFIG(tabletevent)
    virtual void tabletEvent(QTabletEvent *event);
#ifndef QT_NO_ACTION
    virtual void actionEvent(QActionEvent *event);

    virtual void dragEnterEvent(QDragEnterEvent *event);
    virtual void dragMoveEvent(QDragMoveEvent *event);
    virtual void dragLeaveEvent(QDragLeaveEvent *event);
    virtual void dropEvent(QDropEvent *event);

    virtual void showEvent(QShowEvent *event);
    virtual void hideEvent(QHideEvent *event);
    virtual bool nativeEvent(const QByteArray &eventType, void *message, long *result);

    // Misc. protected functions
    virtual void changeEvent(QEvent *);

You have to disable the input handling in Urho3D. If you need more than one instance of Urho3D running then there’s some tweaks you have to do to the handling of MM_FREE in Input.cpp.

When hosting you definitely want QT to be in charge as SDL input capture and handling is complete garbage anyways. Using QT for input will get you reliable captures, while SDL stands around wearing a wife beater and hurling slurs instead of doing anything to help you out.

But why would you do that?

I use multiple viewports instead. They are rendered to a texture using manual updates, which is then converted to a QPixmap. This way everything remains within the same context.

I decided to use QT only for the keyboard events because it’s apparently blocking the signals to Urho.

Heres a sample starter project integrating with qt if anyone is interested. Theres a handler for the keyboard and it uses a q timer and a widget as the external render window.

1 Like

Isolation only really. It would be nice to support multiple heads someday.

QPixmap or GL context sharing works.

1 Like