mythpainterwindow.h

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#ifndef MYTHPAINTERWINDOW_H
#define MYTHPAINTERWINDOW_H
 
// Qt
#include <QTimer>
#include <QWidget>
 
// MythTV
#include "mythuiexp.h"
#include "mythrender_base.h"
 
#ifdef USING_WAYLANDEXTRAS
class MythWaylandDevice;
#endif
 
// Not entirely sure when this started and was fixed (if it is fixed?)
// no issue with 5.11 - broken in 5.14.2, I'm guessing introduced with:-
// https://github.com/qt/qtwayland/commit/88a0246a46c30e08e9730d16cf8739773447d058
// but that was meant to be fixed in:-
// https://github.com/qt/qtwayland/commit/7451faab740ec6294159be60d8a713f5e8070c09
// Ringfence here to ensure the workaround does not live on forever.
//
// Note: There appears to be an additional, possibly related issue running Ubuntu under
// Wayland (20.10, Qt 5.14.2) and using XCB (not Wayland directly). On startup
// the UI is unresponsive and paint events are received roughly once per second.
// Forcing an expose event (al-tab away and back) fixes it - otherwise it resolves
// itself after 10-15seconds. The following define can be enabled to debug events
// received by the window
//#define DEBUG_PAINTERWIN_EVENTS
 
#if QT_VERSION < QT_VERSION_CHECK(5,15,0)
#define USING_WAYLAND_EXPOSE_HACK 1
#endif
 
class MythMainWindow;
class MythPainter;
 
class MythPainterWindow : public QWidget
{
    Q_OBJECT
 
  public:
    static MUI_PUBLIC QString GetDefaultPainter();
    static MUI_PUBLIC QStringList GetPainters();
    static QString CreatePainters(MythMainWindow* MainWin,
                                  MythPainterWindow*& PaintWin,
                                  MythPainter*& Paint);
    static void    DestroyPainters(MythPainterWindow*& PaintWin,
                                   MythPainter*& Painter);
 
    MythRender* GetRenderDevice();
    bool        RenderIsShared ();
    void        resizeEvent    (QResizeEvent* /*ResizeEvent*/) override;
#if defined(DEBUG_PAINTERWIN_EVENTS)
    bool        event(QEvent* Event) override;
#endif
 
  protected:
    explicit MythPainterWindow(MythMainWindow* MainWin);
   ~MythPainterWindow() override;
 
    MythRender* m_render { nullptr };
 
  private:
    Q_DISABLE_COPY(MythPainterWindow)
 
 
#ifdef USING_WAYLAND_EXPOSE_HACK
  protected slots:
    void CheckWindowIsExposed();
 
  private:
    QTimer* m_exposureCheckTimer { nullptr };
#endif
#ifdef USING_WAYLANDEXTRAS
    MythWaylandDevice* m_waylandDev { nullptr };
#endif
};
 
#endif