GL paint-flushing guard re-work.

Unfortunately, since we can have 2x SalGraphics' on a OutputDevice,
and one of these can be a printer - things got very confused around
which context to glFlush. This de-tangles the various reference-counts.

Conflicts:
vcl/inc/generic/genpspgraphics.h
vcl/win/source/gdi/salgdi.cxx

Change-Id: I1062be0b02a91fc9009deaa3ec29c5dbb227df20
Reviewed-on: https://gerrit.libreoffice.org/18611
Reviewed-by: Tor Lillqvist <tml@collabora.com>
Tested-by: Tor Lillqvist <tml@collabora.com>

17 files changed, 77 insertions, 88 deletions

diff --git a/include/vcl/outdev.hxx b/include/vcl/outdev.hxx
index f0057b3b54c0..dbd57e6ad339 100644
--- a/include/vcl/outdev.hxx
+++ b/include/vcl/outdev.hxx
@@ -608,9 +608,21 @@ public:
                                     const Point& rSrcPt,  const Size& rSrcSize,
                                     bool bWindowInvalidate = false );
 
-    // Call before and after a paint operation to reduce flushing
-    void                        BeginPaint();
-    void                        EndPaint();
+    /**
+     * Instantiate across a paint operation to defer flushing
+     * to the end.
+     *
+     * NB. holding a handle avoids problems with
+     * the underlying SalGraphics and it's implementation
+     * changing.
+     */
+    class PaintScope {
+        void *pHandle;
+    public:
+        PaintScope(OutputDevice *);
+        ~PaintScope();
+        void flush();
+    };
 
 protected:
 
diff --git a/vcl/inc/generic/genpspgraphics.h b/vcl/inc/generic/genpspgraphics.h
index 8b78faa8d0b1..2049e26aa651 100644
--- a/vcl/inc/generic/genpspgraphics.h
+++ b/vcl/inc/generic/genpspgraphics.h
@@ -208,9 +208,6 @@ public:
     virtual css::uno::Any   GetNativeSurfaceHandle(cairo::SurfaceSharedPtr& rSurface, const basegfx::B2ISize& rSize) const SAL_OVERRIDE;
 
     virtual SystemFontData  GetSysFontData( int nFallbacklevel ) const SAL_OVERRIDE;
-
-    virtual void BeginPaint() SAL_OVERRIDE { };
-    virtual void EndPaint() SAL_OVERRIDE { };
 };
 
 #endif // INCLUDED_VCL_INC_GENERIC_GENPSPGRAPHICS_H
diff --git a/vcl/inc/headless/svpgdi.hxx b/vcl/inc/headless/svpgdi.hxx
index 9b8a25a6c414..f4503e8f9824 100644
--- a/vcl/inc/headless/svpgdi.hxx
+++ b/vcl/inc/headless/svpgdi.hxx
@@ -215,9 +215,6 @@ public:
     void                    clipRegion(cairo_t* cr);
 
 #endif // ENABLE_CAIRO_CANVAS
-
-    virtual void            BeginPaint() SAL_OVERRIDE { };
-    virtual void            EndPaint() SAL_OVERRIDE { };
 };
 
 #endif
diff --git a/vcl/inc/openglgdiimpl.hxx b/vcl/inc/openglgdiimpl.hxx
index e16dd611dd77..55f2e7039471 100644
--- a/vcl/inc/openglgdiimpl.hxx
+++ b/vcl/inc/openglgdiimpl.hxx
@@ -326,8 +326,7 @@ public:
 
     virtual bool drawGradient(const tools::PolyPolygon& rPolygon, const Gradient& rGradient) SAL_OVERRIDE;
 
-    virtual void beginPaint() SAL_OVERRIDE;
-    virtual void endPaint() SAL_OVERRIDE;
+    virtual OpenGLContext *beginPaint() SAL_OVERRIDE;
 private:
 };
 
diff --git a/vcl/inc/quartz/salgdi.h b/vcl/inc/quartz/salgdi.h
index 12c314482bba..518390ccf994 100644
--- a/vcl/inc/quartz/salgdi.h
+++ b/vcl/inc/quartz/salgdi.h
@@ -421,9 +421,6 @@ public:
     virtual css::uno::Any   GetNativeSurfaceHandle(cairo::SurfaceSharedPtr& rSurface, const ::basegfx::B2ISize& rSize) const SAL_OVERRIDE;
     virtual SystemFontData  GetSysFontData( int /* nFallbacklevel */ ) const SAL_OVERRIDE;
 
-    virtual void            BeginPaint() SAL_OVERRIDE { };
-    virtual void            EndPaint() SAL_OVERRIDE { };
-
 private:
     // differences between VCL, Quartz and kHiThemeOrientation coordinate systems
     // make some graphics seem to be vertically-mirrored from a VCL perspective
diff --git a/vcl/inc/salgdi.hxx b/vcl/inc/salgdi.hxx
index f00aae421d13..afd3b429fcdc 100644
--- a/vcl/inc/salgdi.hxx
+++ b/vcl/inc/salgdi.hxx
@@ -433,8 +433,7 @@ public:
                                     sal_uInt8 nTransparency,
                                     const OutputDevice *pOutDev );
 
-    virtual void                BeginPaint() = 0;
-    virtual void                EndPaint() = 0;
+    virtual OpenGLContext      *BeginPaint() { return NULL; }
 
     virtual SystemGraphicsData  GetGraphicsData() const = 0;
 
diff --git a/vcl/inc/salgdiimpl.hxx b/vcl/inc/salgdiimpl.hxx
index b29405d73f5f..97daa8081040 100644
--- a/vcl/inc/salgdiimpl.hxx
+++ b/vcl/inc/salgdiimpl.hxx
@@ -36,6 +36,7 @@ class SalGraphics;
 class SalBitmap;
 class SalFrame;
 class Gradient;
+class OpenGLContext;
 class SalVirtualDevice;
 
 class VCL_PLUGIN_PUBLIC SalGraphicsImpl
@@ -216,8 +217,7 @@ public:
 
     virtual bool drawGradient(const tools::PolyPolygon& rPolygon, const Gradient& rGradient) = 0;
 
-    virtual void beginPaint() = 0;
-    virtual void endPaint() = 0;
+    virtual OpenGLContext *beginPaint() { return NULL; }
 };
 
 #endif
diff --git a/vcl/inc/unx/salgdi.h b/vcl/inc/unx/salgdi.h
index a44ef1edfa72..84f1e8ff14eb 100644
--- a/vcl/inc/unx/salgdi.h
+++ b/vcl/inc/unx/salgdi.h
@@ -269,8 +269,7 @@ public:
     virtual css::uno::Any           GetNativeSurfaceHandle(cairo::SurfaceSharedPtr& rSurface, const basegfx::B2ISize& rSize) const SAL_OVERRIDE;
     virtual SystemFontData          GetSysFontData( int nFallbackLevel ) const SAL_OVERRIDE;
 
-    virtual void                    BeginPaint() SAL_OVERRIDE;
-    virtual void                    EndPaint() SAL_OVERRIDE;
+    virtual OpenGLContext          *BeginPaint() SAL_OVERRIDE;
 
     bool TryRenderCachedNativeControl(ControlCacheKey& aControlCacheKey,
                                       int nX, int nY);
diff --git a/vcl/inc/win/salgdi.h b/vcl/inc/win/salgdi.h
index f499a31d4e8e..18b7ecfb3c2e 100644
--- a/vcl/inc/win/salgdi.h
+++ b/vcl/inc/win/salgdi.h
@@ -445,8 +445,7 @@ public:
     virtual css::uno::Any      GetNativeSurfaceHandle(cairo::SurfaceSharedPtr& rSurface, const ::basegfx::B2ISize& rSize) const SAL_OVERRIDE;
     virtual SystemFontData     GetSysFontData( int nFallbacklevel ) const SAL_OVERRIDE;
 
-    virtual void               BeginPaint() SAL_OVERRIDE;
-    virtual void               EndPaint() SAL_OVERRIDE;
+    virtual OpenGLContext     *BeginPaint() SAL_OVERRIDE;
 
     /// Update settings based on the platform values
     static void updateSettingsNative( AllSettings& rSettings );
diff --git a/vcl/opengl/gdiimpl.cxx b/vcl/opengl/gdiimpl.cxx
index 9ea8a7c87fc8..d452f5d18cd8 100644
--- a/vcl/opengl/gdiimpl.cxx
+++ b/vcl/opengl/gdiimpl.cxx
@@ -1873,30 +1873,12 @@ bool OpenGLSalGraphicsImpl::drawGradient(const tools::PolyPolygon& rPolyPoly,
     return true;
 }
 
-void OpenGLSalGraphicsImpl::beginPaint()
+OpenGLContext *OpenGLSalGraphicsImpl::beginPaint()
 {
-    if( !AcquireContext() )
-        return;
-
-    mpContext->mnPainting++;
-}
-
-void OpenGLSalGraphicsImpl::endPaint()
-{
-    if( !AcquireContext() )
-        return;
-
-    mpContext->mnPainting--;
-    assert( mpContext->mnPainting >= 0 );
-    if( mpContext->mnPainting == 0 && !mbOffscreen )
-    {
-        mpContext->makeCurrent();
-        mpContext->AcquireDefaultFramebuffer();
-        glFlush();
-        mpContext->swapBuffers();
-
-        CHECK_GL_ERROR();
-    }
+    if( mbOffscreen || !AcquireContext() )
+        return NULL;
+    else
+        return mpContext.get();
 }
 
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/vcl/source/opengl/OpenGLHelper.cxx b/vcl/source/opengl/OpenGLHelper.cxx
index 1b48fec9216a..58408538dcf7 100644
--- a/vcl/source/opengl/OpenGLHelper.cxx
+++ b/vcl/source/opengl/OpenGLHelper.cxx
@@ -27,7 +27,7 @@
 #include <vector>
 
 #include "svdata.hxx"
-
+#include "salgdi.hxx"
 #include "salinst.hxx"
 #include "opengl/zone.hxx"
 #include "opengl/watchdog.hxx"
@@ -816,4 +816,48 @@ GLXFBConfig OpenGLHelper::GetPixmapFBConfig( Display* pDisplay, bool& bInverted
 
 #endif
 
+OutputDevice::PaintScope::PaintScope(OutputDevice *pDev)
+    : pHandle( NULL )
+{
+    if( pDev->mpGraphics || pDev->AcquireGraphics() )
+    {
+        OpenGLContext *pContext = pDev->mpGraphics->BeginPaint();
+        if( pContext )
+        {
+            assert( pContext->mnPainting >= 0 );
+            pContext->mnPainting++;
+            pContext->acquire();
+            pHandle = static_cast<void *>( pContext );
+        }
+    }
+}
+
+/**
+ * Flush all the queued rendering commands to the screen for this context.
+ */
+void OutputDevice::PaintScope::flush()
+{
+    if( pHandle )
+    {
+        OpenGLContext *pContext = static_cast<OpenGLContext *>( pHandle );
+        pHandle = NULL;
+        pContext->mnPainting--;
+        assert( pContext->mnPainting >= 0 );
+        if( pContext->mnPainting == 0 )
+        {
+            pContext->makeCurrent();
+            pContext->AcquireDefaultFramebuffer();
+            glFlush();
+            pContext->swapBuffers();
+            CHECK_GL_ERROR();
+        }
+        pContext->release();
+    }
+}
+
+OutputDevice::PaintScope::~PaintScope()
+{
+    flush();
+}
+
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/vcl/source/outdev/outdev.cxx b/vcl/source/outdev/outdev.cxx
index 0d9842de39dc..1c295599af19 100644
--- a/vcl/source/outdev/outdev.cxx
+++ b/vcl/source/outdev/outdev.cxx
@@ -870,16 +870,4 @@ bool OutputDevice::DrawEPS( const Point& rPoint, const Size& rSize,
     return bDrawn;
 }
 
-void OutputDevice::BeginPaint()
-{
-    if( mpGraphics || AcquireGraphics() )
-        mpGraphics->BeginPaint();
-}
-
-void OutputDevice::EndPaint()
-{
-    if( mpGraphics || AcquireGraphics() )
-        mpGraphics->EndPaint();
-}
-
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/vcl/source/window/paint.cxx b/vcl/source/window/paint.cxx
index ae846ae59a54..79aa1ed37438 100644
--- a/vcl/source/window/paint.cxx
+++ b/vcl/source/window/paint.cxx
@@ -276,7 +276,7 @@ void PaintHelper::DoPaint(const vcl::Region* pRegion)
         VCL_GL_INFO("vcl.opengl", "PaintHelper::DoPaint on " <<
                     typeid( *m_pWindow ).name() << " '" << m_pWindow->GetText() << "' begin");
 
-        m_pWindow->BeginPaint();
+        OutputDevice::PaintScope aScope( m_pWindow );
 
         // double-buffering: setup the buffer if it does not exist
         if (!pFrameData->mbInBufferedPaint && m_pWindow->SupportsDoubleBuffering())
@@ -306,8 +306,6 @@ void PaintHelper::DoPaint(const vcl::Region* pRegion)
             m_pWindow->Paint(*m_pWindow, m_aPaintRect);
         }
 
-        m_pWindow->EndPaint();
-
         VCL_GL_INFO("vcl.opengl", "PaintHelper::DoPaint end on " <<
                     typeid( *m_pWindow ).name() << " '" << m_pWindow->GetText() << "'");
     }
@@ -629,10 +627,8 @@ void Window::ImplCallOverlapPaint()
     {
         // - RTL - notify ImplCallPaint to check for re-mirroring (CHECKRTL)
         //         because we were called from the Sal layer
-        OutputDevice *pOutDev = GetOutDev();
-        pOutDev->BeginPaint();
+        OutputDevice::PaintScope aScope( GetOutDev() );
         ImplCallPaint(NULL, mpWindowImpl->mnPaintFlags /*| IMPL_PAINT_CHECKRTL */);
-        pOutDev->EndPaint();
     }
 }
 
@@ -651,7 +647,7 @@ IMPL_LINK_NOARG_TYPED(Window, ImplHandlePaintHdl, Idle *, void)
         return;
     }
 
-    BeginPaint();
+    OutputDevice::PaintScope aScope(this);
 
     // save paint events until resizing or initial sizing done
     if (!ImplDoTiledRendering() && mpWindowImpl->mbFrame &&
@@ -664,15 +660,13 @@ IMPL_LINK_NOARG_TYPED(Window, ImplHandlePaintHdl, Idle *, void)
     {
         ImplCallOverlapPaint();
     }
-
-    EndPaint();
 }
 
 IMPL_LINK_NOARG_TYPED(Window, ImplHandleResizeTimerHdl, Idle *, void)
 {
     if( mpWindowImpl->mbReallyVisible )
     {
-        BeginPaint();
+        OutputDevice::PaintScope aScope(this);
 
         ImplCallResize();
         if( ImplDoTiledRendering() )
@@ -684,8 +678,6 @@ IMPL_LINK_NOARG_TYPED(Window, ImplHandleResizeTimerHdl, Idle *, void)
             mpWindowImpl->mpFrameData->maPaintIdle.Stop();
             mpWindowImpl->mpFrameData->maPaintIdle.GetIdleHdl().Call( NULL );
         }
-
-        EndPaint();
     }
 }
 
diff --git a/vcl/unx/generic/gdi/gdiimpl.hxx b/vcl/unx/generic/gdi/gdiimpl.hxx
index 2cf40f9ce701..6e8a2788daf7 100644
--- a/vcl/unx/generic/gdi/gdiimpl.hxx
+++ b/vcl/unx/generic/gdi/gdiimpl.hxx
@@ -275,9 +275,6 @@ public:
 
     virtual bool drawGradient(const tools::PolyPolygon& rPolygon, const Gradient& rGradient) SAL_OVERRIDE;
 
-    virtual void beginPaint() SAL_OVERRIDE { }
-    virtual void endPaint() SAL_OVERRIDE { }
-
 public:
     // implementation of X11GraphicsImpl
 
diff --git a/vcl/unx/generic/gdi/salgdi.cxx b/vcl/unx/generic/gdi/salgdi.cxx
index e9262e13e311..e2a25b5de4b6 100644
--- a/vcl/unx/generic/gdi/salgdi.cxx
+++ b/vcl/unx/generic/gdi/salgdi.cxx
@@ -548,16 +548,11 @@ bool X11SalGraphics::drawGradient(const tools::PolyPolygon& rPoly, const Gradien
     return mxImpl->drawGradient(rPoly, rGradient);
 }
 
-void X11SalGraphics::BeginPaint()
+OpenGLContext *X11SalGraphics::BeginPaint()
 {
     return mxImpl->beginPaint();
 }
 
-void X11SalGraphics::EndPaint()
-{
-    return mxImpl->endPaint();
-}
-
 SalGeometryProvider *X11SalGraphics::GetGeometryProvider() const
 {
     if (m_pFrame)
diff --git a/vcl/win/source/gdi/gdiimpl.hxx b/vcl/win/source/gdi/gdiimpl.hxx
index 82a8333eb49f..8e7d7f8b427c 100644
--- a/vcl/win/source/gdi/gdiimpl.hxx
+++ b/vcl/win/source/gdi/gdiimpl.hxx
@@ -225,9 +225,6 @@ public:
     virtual bool drawGradient(const tools::PolyPolygon& rPolygon,
             const Gradient& rGradient) SAL_OVERRIDE;
 
-    virtual void beginPaint() SAL_OVERRIDE { }
-    virtual void endPaint() SAL_OVERRIDE { }
-
     virtual bool TryRenderCachedNativeControl(ControlCacheKey& rControlCacheKey, int nX, int nY);
 
     virtual bool RenderAndCacheNativeControl(OpenGLCompatibleDC& rWhite, OpenGLCompatibleDC& rBlack,
diff --git a/vcl/win/source/gdi/salgdi.cxx b/vcl/win/source/gdi/salgdi.cxx
index 99cebeee5fbf..3ed0c073c05c 100644
--- a/vcl/win/source/gdi/salgdi.cxx
+++ b/vcl/win/source/gdi/salgdi.cxx
@@ -1210,14 +1210,9 @@ css::uno::Any WinSalGraphics::GetNativeSurfaceHandle(cairo::SurfaceSharedPtr& rS
     return css::uno::Any( args );
 }
 
-void WinSalGraphics::BeginPaint()
+OpenGLContext *WinSalGraphics::BeginPaint()
 {
     return mpImpl->beginPaint();
 }
 
-void WinSalGraphics::EndPaint()
-{
-    return mpImpl->endPaint();
-}
-
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */