Qt5 implement SalSurface support for cairo

Current qt5+cairo uses the plain VCL canvas. This patch is just a
copy of Gtk3Surface (minus comments) with a different update call.
This way the Cairo path now uses the Cairo canvas instead.

It fixes at least tdf#122668 for me, but other Impress bugs might
be fixed this way too.

Change-Id: Iba511c851001753328293c28e53eaa4acc4315d0
Reviewed-on: https://gerrit.libreoffice.org/72921
Reviewed-by: Michael Weghorn <m.weghorn@posteo.de>
Tested-by: Jenkins
Reviewed-by: Aleksei Nikiforov <darktemplar@basealt.ru>

1 files changed, 13 insertions, 10 deletions

diff --git a/vcl/inc/qt5/Qt5Frame.hxx b/vcl/inc/qt5/Qt5Frame.hxx
index 9b9c13b4b7fa..a42a95aac3bd 100644
--- a/vcl/inc/qt5/Qt5Frame.hxx
+++ b/vcl/inc/qt5/Qt5Frame.hxx
@@ -30,18 +30,19 @@
 
 #include <QtCore/QObject>
 
+class Qt5DragSource;
+class Qt5DropTarget;
 class Qt5Graphics;
 class Qt5Instance;
-class Qt5Menu;
-class QWidget;
 class Qt5MainWindow;
-class Qt5DragSource;
-class Qt5DropTarget;
+class Qt5Menu;
+class Qt5SvpGraphics;
+
+class QImage;
 class QMimeData;
 class QPaintDevice;
 class QScreen;
-class QImage;
-class SvpSalGraphics;
+class QWidget;
 
 class VCLPLUG_QT5_PUBLIC Qt5Frame : public QObject, public SalFrame
 {
@@ -56,11 +57,11 @@ class VCLPLUG_QT5_PUBLIC Qt5Frame : public QObject, public SalFrame
     std::unique_ptr<QImage> m_pQImage;
     std::unique_ptr<Qt5Graphics> m_pQt5Graphics;
     UniqueCairoSurface m_pSurface;
-    std::unique_ptr<SvpSalGraphics> m_pOurSvpGraphics;
+    std::unique_ptr<Qt5SvpGraphics> m_pOurSvpGraphics;
     // in base class, this ptr is the same as m_pOurSvpGraphic
     // in derived class, it can point to a derivative
-    // of SvpSalGraphics (which the derived class then owns)
-    SvpSalGraphics* m_pSvpGraphics;
+    // of Qt5SvpGraphics (which the derived class then owns)
+    Qt5SvpGraphics* m_pSvpGraphics;
     DamageHandler m_aDamageHandler;
     QRegion m_aRegion;
     bool m_bNullRegion;
@@ -124,7 +125,7 @@ public:
     void Damage(sal_Int32 nExtentsX, sal_Int32 nExtentsY, sal_Int32 nExtentsWidth,
                 sal_Int32 nExtentsHeight) const;
 
-    virtual void InitSvpSalGraphics(SvpSalGraphics* pSvpSalGraphics);
+    void InitQt5SvpGraphics(Qt5SvpGraphics* pQt5SvpGraphics);
     virtual SalGraphics* AcquireGraphics() override;
     virtual void ReleaseGraphics(SalGraphics* pGraphics) override;
 
@@ -190,6 +191,8 @@ public:
     virtual void SetApplicationID(const OUString&) override;
 
     inline bool CallCallback(SalEvent nEvent, const void* pEvent) const;
+
+    cairo_t* getCairoContext() const;
 };
 
 inline bool Qt5Frame::CallCallback(SalEvent nEvent, const void* pEvent) const