masses of coverity FORWARD_NULL warnings from copied assert

Change-Id: I8f698bbcf4d53a4477cc0ee0c3f2c7f08e521f8a

15 files changed, 75 insertions, 67 deletions

diff --git a/vcl/source/outdev/bitmap.cxx b/vcl/source/outdev/bitmap.cxx
index f59e441523a6..718cef96f455 100644
--- a/vcl/source/outdev/bitmap.cxx
+++ b/vcl/source/outdev/bitmap.cxx
@@ -36,7 +36,7 @@
 
 void OutputDevice::DrawBitmap( const Point& rDestPt, const Bitmap& rBitmap )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     const Size aSizePix( rBitmap.GetSizePixel() );
     DrawBitmap( rDestPt, PixelToLogic( aSizePix ), Point(), aSizePix, rBitmap, MetaActionType::BMP );
@@ -44,7 +44,7 @@ void OutputDevice::DrawBitmap( const Point& rDestPt, const Bitmap& rBitmap )
 
 void OutputDevice::DrawBitmap( const Point& rDestPt, const Size& rDestSize, const Bitmap& rBitmap )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     DrawBitmap( rDestPt, rDestSize, Point(), rBitmap.GetSizePixel(), rBitmap, MetaActionType::BMPSCALE );
 }
@@ -54,7 +54,7 @@ void OutputDevice::DrawBitmap( const Point& rDestPt, const Size& rDestSize,
                                    const Point& rSrcPtPixel, const Size& rSrcSizePixel,
                                    const Bitmap& rBitmap, const MetaActionType nAction )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if( ImplIsRecordLayout() )
         return;
@@ -236,7 +236,7 @@ Bitmap OutputDevice::GetDownsampledBitmap( const Size& rDstSz,
 void OutputDevice::DrawBitmapEx( const Point& rDestPt,
                                  const BitmapEx& rBitmapEx )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if( ImplIsRecordLayout() )
         return;
@@ -255,7 +255,7 @@ void OutputDevice::DrawBitmapEx( const Point& rDestPt,
 void OutputDevice::DrawBitmapEx( const Point& rDestPt, const Size& rDestSize,
                                  const BitmapEx& rBitmapEx )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if( ImplIsRecordLayout() )
         return;
@@ -275,7 +275,7 @@ void OutputDevice::DrawBitmapEx( const Point& rDestPt, const Size& rDestSize,
                                  const Point& rSrcPtPixel, const Size& rSrcSizePixel,
                                  const BitmapEx& rBitmapEx, const MetaActionType nAction )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if( ImplIsRecordLayout() )
         return;
@@ -492,7 +492,7 @@ void OutputDevice::DrawDeviceBitmap( const Point& rDestPt, const Size& rDestSize
                                      const Point& rSrcPtPixel, const Size& rSrcSizePixel,
                                      BitmapEx& rBitmapEx )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if (rBitmapEx.IsAlpha())
     {
@@ -622,7 +622,7 @@ void OutputDevice::DrawDeviceAlphaBitmap( const Bitmap& rBmp, const AlphaMask& r
                                     const Point& rDestPt, const Size& rDestSize,
                                     const Point& rSrcPtPixel, const Size& rSrcSizePixel )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     Point     aOutPt(LogicToPixel(rDestPt));
     Size      aOutSz(LogicToPixel(rDestSize));
@@ -918,7 +918,7 @@ private:
 
 void OutputDevice::DrawDeviceAlphaBitmapSlowPath(const Bitmap& rBitmap, const AlphaMask& rAlpha, Rectangle aDstRect, Rectangle aBmpRect, Size& aOutSize, Point& aOutPoint)
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     VirtualDevice* pOldVDev = mpAlphaVDev;
 
@@ -1036,7 +1036,7 @@ bool OutputDevice::DrawTransformBitmapExDirect(
         const basegfx::B2DHomMatrix& aFullTransform,
         const BitmapEx& rBitmapEx)
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     bool bDone = false;
 
@@ -1157,7 +1157,7 @@ void OutputDevice::DrawTransformedBitmapEx(
     const basegfx::B2DHomMatrix& rTransformation,
     const BitmapEx& rBitmapEx)
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if( ImplIsRecordLayout() )
         return;
@@ -1330,7 +1330,7 @@ namespace
 
 void OutputDevice::DrawImage( const Point& rPos, const Image& rImage, DrawImageFlags nStyle )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     DrawImage( rPos, Size(), rImage, nStyle );
 }
@@ -1338,7 +1338,7 @@ void OutputDevice::DrawImage( const Point& rPos, const Image& rImage, DrawImageF
 void OutputDevice::DrawImage( const Point& rPos, const Size& rSize,
                               const Image& rImage, DrawImageFlags nStyle )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     bool bIsSizeValid = rSize.getWidth() != 0 && rSize.getHeight() != 0;
 
diff --git a/vcl/source/outdev/curvedshapes.cxx b/vcl/source/outdev/curvedshapes.cxx
index db8f7d6ad7de..0190a4d67fd4 100644
--- a/vcl/source/outdev/curvedshapes.cxx
+++ b/vcl/source/outdev/curvedshapes.cxx
@@ -25,7 +25,7 @@
 
 void OutputDevice::DrawEllipse( const Rectangle& rRect )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if ( mpMetaFile )
         mpMetaFile->AddAction( new MetaEllipseAction( rRect ) );
@@ -73,7 +73,7 @@ void OutputDevice::DrawEllipse( const Rectangle& rRect )
 void OutputDevice::DrawArc( const Rectangle& rRect,
                             const Point& rStartPt, const Point& rEndPt )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if ( mpMetaFile )
         mpMetaFile->AddAction( new MetaArcAction( rRect, rStartPt, rEndPt ) );
@@ -117,7 +117,7 @@ void OutputDevice::DrawArc( const Rectangle& rRect,
 void OutputDevice::DrawPie( const Rectangle& rRect,
                             const Point& rStartPt, const Point& rEndPt )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if ( mpMetaFile )
         mpMetaFile->AddAction( new MetaPieAction( rRect, rStartPt, rEndPt ) );
@@ -168,7 +168,7 @@ void OutputDevice::DrawPie( const Rectangle& rRect,
 void OutputDevice::DrawChord( const Rectangle& rRect,
                               const Point& rStartPt, const Point& rEndPt )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if ( mpMetaFile )
         mpMetaFile->AddAction( new MetaChordAction( rRect, rStartPt, rEndPt ) );
diff --git a/vcl/source/outdev/gradient.cxx b/vcl/source/outdev/gradient.cxx
index ca0e9490dc97..41c245558899 100644
--- a/vcl/source/outdev/gradient.cxx
+++ b/vcl/source/outdev/gradient.cxx
@@ -32,7 +32,7 @@
 void OutputDevice::DrawGradient( const Rectangle& rRect,
                                  const Gradient& rGradient )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     // Convert rectangle to a tools::PolyPolygon by first converting to a Polygon
     Polygon aPolygon ( rRect );
@@ -44,7 +44,7 @@ void OutputDevice::DrawGradient( const Rectangle& rRect,
 void OutputDevice::DrawGradient( const tools::PolyPolygon& rPolyPoly,
                                  const Gradient& rGradient )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if ( mnDrawMode & DrawModeFlags::NoGradient )
         return;     // nothing to draw!
@@ -172,7 +172,7 @@ void OutputDevice::ClipAndDrawGradientMetafile ( const Gradient &rGradient, cons
 void OutputDevice::DrawGradientToMetafile ( const tools::PolyPolygon& rPolyPoly,
                                             const Gradient& rGradient )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if ( !mpMetaFile )
         return;
@@ -260,7 +260,7 @@ void OutputDevice::DrawLinearGradient( const Rectangle& rRect,
                                        const Gradient& rGradient,
                                        const tools::PolyPolygon* pClixPolyPoly )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     // get BoundRect of rotated rectangle
     Rectangle aRect;
@@ -438,11 +438,19 @@ void OutputDevice::DrawLinearGradient( const Rectangle& rRect,
     }
 }
 
+void OutputDevice::assert_if_double_buffered_window() const
+{
+#ifndef NDEBUG
+    const vcl::Window *pWindow = dynamic_cast<const vcl::Window*>(this);
+    assert(!pWindow || !pWindow->SupportsDoubleBuffering());
+#endif
+}
+
 void OutputDevice::DrawComplexGradient( const Rectangle& rRect,
                                         const Gradient& rGradient,
                                         const tools::PolyPolygon* pClixPolyPoly )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     // Determine if we output via Polygon or PolyPolygon
     // For all rasteroperations other then Overpaint always use PolyPolygon,
@@ -608,7 +616,7 @@ void OutputDevice::DrawComplexGradient( const Rectangle& rRect,
 void OutputDevice::DrawLinearGradientToMetafile( const Rectangle& rRect,
                                                  const Gradient& rGradient )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     // get BoundRect of rotated rectangle
     Rectangle aRect;
@@ -788,7 +796,7 @@ void OutputDevice::DrawLinearGradientToMetafile( const Rectangle& rRect,
 void OutputDevice::DrawComplexGradientToMetafile( const Rectangle& rRect,
                                                   const Gradient& rGradient )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     // Determine if we output via Polygon or PolyPolygon
     // For all rasteroperations other then Overpaint always use PolyPolygon,
diff --git a/vcl/source/outdev/hatch.cxx b/vcl/source/outdev/hatch.cxx
index a33fae384222..1ccdcc7c4195 100644
--- a/vcl/source/outdev/hatch.cxx
+++ b/vcl/source/outdev/hatch.cxx
@@ -44,7 +44,7 @@ extern "C" int SAL_CALL HatchCmpFnc( const void* p1, const void* p2 )
 
 void OutputDevice::DrawHatch( const tools::PolyPolygon& rPolyPoly, const Hatch& rHatch )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     Hatch aHatch( rHatch );
 
@@ -139,7 +139,7 @@ void OutputDevice::AddHatchActions( const tools::PolyPolygon& rPolyPoly, const H
 
 void OutputDevice::DrawHatch( const tools::PolyPolygon& rPolyPoly, const Hatch& rHatch, bool bMtf )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if(rPolyPoly.Count())
     {
@@ -322,7 +322,7 @@ void OutputDevice::CalcHatchValues( const Rectangle& rRect, long nDist, sal_uInt
 void OutputDevice::DrawHatchLine( const Line& rLine, const tools::PolyPolygon& rPolyPoly,
                                       Point* pPtBuffer, bool bMtf )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     double  fX, fY;
     long    nAdd, nPCounter = 0;
diff --git a/vcl/source/outdev/line.cxx b/vcl/source/outdev/line.cxx
index f37280fbb52f..f8eba4ab6089 100644
--- a/vcl/source/outdev/line.cxx
+++ b/vcl/source/outdev/line.cxx
@@ -35,7 +35,7 @@
 void OutputDevice::DrawLine( const Point& rStartPt, const Point& rEndPt,
                              const LineInfo& rLineInfo )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if ( rLineInfo.IsDefault() )
     {
@@ -89,7 +89,7 @@ void OutputDevice::DrawLine( const Point& rStartPt, const Point& rEndPt,
 
 void OutputDevice::DrawLine( const Point& rStartPt, const Point& rEndPt )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if ( mpMetaFile )
         mpMetaFile->AddAction( new MetaLineAction( rStartPt, rEndPt ) );
diff --git a/vcl/source/outdev/mask.cxx b/vcl/source/outdev/mask.cxx
index 29737a1d5f75..facbb9ae7c04 100644
--- a/vcl/source/outdev/mask.cxx
+++ b/vcl/source/outdev/mask.cxx
@@ -34,7 +34,7 @@ extern const sal_uLong nVCLLut[ 256 ];
 void OutputDevice::DrawMask( const Point& rDestPt,
                              const Bitmap& rBitmap, const Color& rMaskColor )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     const Size aSizePix( rBitmap.GetSizePixel() );
     DrawMask( rDestPt, PixelToLogic( aSizePix ), Point(), aSizePix, rBitmap, rMaskColor, MetaActionType::MASK );
@@ -43,7 +43,7 @@ void OutputDevice::DrawMask( const Point& rDestPt,
 void OutputDevice::DrawMask( const Point& rDestPt, const Size& rDestSize,
                              const Bitmap& rBitmap, const Color& rMaskColor )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     DrawMask( rDestPt, rDestSize, Point(), rBitmap.GetSizePixel(), rBitmap, rMaskColor, MetaActionType::MASKSCALE );
 }
@@ -53,7 +53,7 @@ void OutputDevice::DrawMask( const Point& rDestPt, const Size& rDestSize,
                              const Bitmap& rBitmap, const Color& rMaskColor,
                              const MetaActionType nAction )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if( ImplIsRecordLayout() )
         return;
@@ -108,7 +108,7 @@ void OutputDevice::DrawDeviceMask( const Bitmap& rMask, const Color& rMaskColor,
                               const Point& rDestPt, const Size& rDestSize,
                               const Point& rSrcPtPixel, const Size& rSrcSizePixel )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     const ImpBitmap* pImpBmp = rMask.ImplGetImpBitmap();
     if ( pImpBmp )
diff --git a/vcl/source/outdev/nativecontrols.cxx b/vcl/source/outdev/nativecontrols.cxx
index 6e9279c8c75c..071102141a31 100644
--- a/vcl/source/outdev/nativecontrols.cxx
+++ b/vcl/source/outdev/nativecontrols.cxx
@@ -273,7 +273,7 @@ bool OutputDevice::DrawNativeControl( ControlType nType,
                             const ImplControlValue& aValue,
                             const OUString& aCaption )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if( !EnableNativeWidget( *this ) )
         return false;
diff --git a/vcl/source/outdev/pixel.cxx b/vcl/source/outdev/pixel.cxx
index c4f65283970f..8310a72c3d0b 100644
--- a/vcl/source/outdev/pixel.cxx
+++ b/vcl/source/outdev/pixel.cxx
@@ -57,7 +57,7 @@ Color OutputDevice::GetPixel( const Point& rPt ) const
 
 void OutputDevice::DrawPixel( const Point& rPt )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if ( mpMetaFile )
         mpMetaFile->AddAction( new MetaPointAction( rPt ) );
@@ -87,7 +87,7 @@ void OutputDevice::DrawPixel( const Point& rPt )
 
 void OutputDevice::DrawPixel( const Point& rPt, const Color& rColor )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     Color aColor = ImplDrawModeToColor( rColor );
 
@@ -116,7 +116,7 @@ void OutputDevice::DrawPixel( const Point& rPt, const Color& rColor )
 
 void OutputDevice::DrawPixel( const Polygon& rPts, const Color* pColors )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if ( !pColors )
     {
@@ -163,7 +163,7 @@ void OutputDevice::DrawPixel( const Polygon& rPts, const Color* pColors )
 
 void OutputDevice::DrawPixel( const Polygon& rPts, const Color& rColor )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if( rColor != COL_TRANSPARENT && ! ImplIsRecordLayout() )
     {
diff --git a/vcl/source/outdev/polygon.cxx b/vcl/source/outdev/polygon.cxx
index c25025c09026..9b703a09be79 100644
--- a/vcl/source/outdev/polygon.cxx
+++ b/vcl/source/outdev/polygon.cxx
@@ -33,7 +33,7 @@
 
 void OutputDevice::DrawPolyPolygon( const tools::PolyPolygon& rPolyPoly )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if( mpMetaFile )
         mpMetaFile->AddAction( new MetaPolyPolygonAction( rPolyPoly ) );
@@ -131,7 +131,7 @@ void OutputDevice::DrawPolyPolygon( const tools::PolyPolygon& rPolyPoly )
 
 void OutputDevice::DrawPolygon( const basegfx::B2DPolygon& rB2DPolygon)
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     // AW: Do NOT paint empty polygons
     if(rB2DPolygon.count())
@@ -143,7 +143,7 @@ void OutputDevice::DrawPolygon( const basegfx::B2DPolygon& rB2DPolygon)
 
 void OutputDevice::DrawPolygon( const Polygon& rPoly )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if( mpMetaFile )
         mpMetaFile->AddAction( new MetaPolygonAction( rPoly ) );
@@ -239,7 +239,7 @@ void OutputDevice::DrawPolygon( const Polygon& rPoly )
 
 void OutputDevice::DrawPolyPolygon( const basegfx::B2DPolyPolygon& rB2DPolyPoly )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if( mpMetaFile )
         mpMetaFile->AddAction( new MetaPolyPolygonAction( tools::PolyPolygon( rB2DPolyPoly ) ) );
diff --git a/vcl/source/outdev/polyline.cxx b/vcl/source/outdev/polyline.cxx
index 236d2cd21671..3be82cfadd9a 100644
--- a/vcl/source/outdev/polyline.cxx
+++ b/vcl/source/outdev/polyline.cxx
@@ -31,7 +31,7 @@
 
 void OutputDevice::DrawPolyLine( const Polygon& rPoly )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if( mpMetaFile )
         mpMetaFile->AddAction( new MetaPolyLineAction( rPoly ) );
@@ -101,7 +101,7 @@ void OutputDevice::DrawPolyLine( const Polygon& rPoly )
 
 void OutputDevice::DrawPolyLine( const Polygon& rPoly, const LineInfo& rLineInfo )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if ( rLineInfo.IsDefault() )
     {
@@ -129,7 +129,7 @@ void OutputDevice::DrawPolyLine( const basegfx::B2DPolygon& rB2DPolygon,
                                  basegfx::B2DLineJoin eLineJoin,
                                  css::drawing::LineCap eLineCap)
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if( mpMetaFile )
     {
@@ -275,7 +275,7 @@ bool OutputDevice::DrawPolyLineDirect( const basegfx::B2DPolygon& rB2DPolygon,
                                        css::drawing::LineCap eLineCap,
                                        bool bBypassAACheck )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     // AW: Do NOT paint empty PolyPolygons
     if(!rB2DPolygon.count())
diff --git a/vcl/source/outdev/rect.cxx b/vcl/source/outdev/rect.cxx
index 44923529c1ad..a9ebc0a676d2 100644
--- a/vcl/source/outdev/rect.cxx
+++ b/vcl/source/outdev/rect.cxx
@@ -29,7 +29,7 @@
 
 void OutputDevice::DrawRect( const Rectangle& rRect )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if ( mpMetaFile )
         mpMetaFile->AddAction( new MetaRectAction( rRect ) );
@@ -68,7 +68,7 @@ void OutputDevice::DrawRect( const Rectangle& rRect )
 void OutputDevice::DrawRect( const Rectangle& rRect,
                              sal_uLong nHorzRound, sal_uLong nVertRound )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if ( mpMetaFile )
         mpMetaFile->AddAction( new MetaRoundRectAction( rRect, nHorzRound, nVertRound ) );
@@ -128,7 +128,7 @@ void OutputDevice::DrawRect( const Rectangle& rRect,
 
 void OutputDevice::DrawCheckered(const Point& rPos, const Size& rSize, sal_uInt32 nLen, Color aStart, Color aEnd)
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     const sal_uInt32 nMaxX(rPos.X() + rSize.Width());
     const sal_uInt32 nMaxY(rPos.Y() + rSize.Height());
@@ -154,7 +154,7 @@ void OutputDevice::DrawCheckered(const Point& rPos, const Size& rSize, sal_uInt3
 
 void OutputDevice::DrawGrid( const Rectangle& rRect, const Size& rDist, DrawGridFlags nFlags )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     Rectangle aDstRect( PixelToLogic( Point() ), GetOutputSize() );
     aDstRect.Intersection( rRect );
diff --git a/vcl/source/outdev/text.cxx b/vcl/source/outdev/text.cxx
index 15e59bf6cd83..639151d50a76 100644
--- a/vcl/source/outdev/text.cxx
+++ b/vcl/source/outdev/text.cxx
@@ -838,7 +838,7 @@ void OutputDevice::DrawText( const Point& rStartPt, const OUString& rStr,
                              MetricVector* pVector, OUString* pDisplayText
                              )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if(nLen == 0x0FFFF)
     {
@@ -961,7 +961,7 @@ void OutputDevice::DrawTextArray( const Point& rStartPt, const OUString& rStr,
                                   const long* pDXAry,
                                   sal_Int32 nIndex, sal_Int32 nLen, SalLayoutFlags flags )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if(nLen == 0x0FFFF)
     {
@@ -1166,7 +1166,7 @@ void OutputDevice::DrawStretchText( const Point& rStartPt, sal_uLong nWidth,
                                     const OUString& rStr,
                                     sal_Int32 nIndex, sal_Int32 nLen)
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if(nIndex < 0 || nIndex == 0x0FFFF || nLen == 0x0FFFF)
     {
@@ -1840,7 +1840,7 @@ void OutputDevice::DrawText( const Rectangle& rRect, const OUString& rOrigStr, D
                              MetricVector* pVector, OUString* pDisplayText,
                              vcl::ITextLayout* _pTextLayout )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if (mpOutDevData->mpRecordLayout)
     {
@@ -2148,7 +2148,7 @@ void OutputDevice::DrawCtrlText( const Point& rPos, const OUString& rStr,
                                  sal_Int32 nIndex, sal_Int32 nLen,
                                  DrawTextFlags nStyle, MetricVector* pVector, OUString* pDisplayText )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if(nLen == 0x0FFFF)
     {
diff --git a/vcl/source/outdev/textline.cxx b/vcl/source/outdev/textline.cxx
index 8e55eca4656e..551e55649cec 100644
--- a/vcl/source/outdev/textline.cxx
+++ b/vcl/source/outdev/textline.cxx
@@ -941,7 +941,7 @@ void OutputDevice::DrawTextLine( const Point& rPos, long nWidth,
                                  FontUnderline eOverline,
                                  bool bUnderlineAbove )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if ( mpMetaFile )
         mpMetaFile->AddAction( new MetaTextLineAction( rPos, nWidth, eStrikeout, eUnderline, eOverline ) );
@@ -985,7 +985,7 @@ void OutputDevice::DrawTextLine( const Point& rPos, long nWidth,
 
 void OutputDevice::DrawWaveLine( const Point& rStartPos, const Point& rEndPos )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if ( !IsDeviceOutputNecessary() || ImplIsRecordLayout() )
         return;
diff --git a/vcl/source/outdev/transparent.cxx b/vcl/source/outdev/transparent.cxx
index 7d4e0270d80d..6827fc3b0f30 100644
--- a/vcl/source/outdev/transparent.cxx
+++ b/vcl/source/outdev/transparent.cxx
@@ -218,7 +218,7 @@ void OutputDevice::ImplPrintTransparent( const Bitmap& rBmp, const Bitmap& rMask
 
 void OutputDevice::DrawTransparent( const basegfx::B2DPolyPolygon& rB2DPolyPoly, double fTransparency)
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     // AW: Do NOT paint empty PolyPolygons
     if(!rB2DPolyPoly.count())
@@ -282,7 +282,7 @@ void OutputDevice::DrawTransparent( const basegfx::B2DPolyPolygon& rB2DPolyPoly,
 
 void OutputDevice::DrawInvisiblePolygon( const tools::PolyPolygon& rPolyPoly )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     // short circuit if the polygon border is invisible too
     if( !mbLineColor )
@@ -298,7 +298,7 @@ void OutputDevice::DrawInvisiblePolygon( const tools::PolyPolygon& rPolyPoly )
 bool OutputDevice::DrawTransparentNatively ( const tools::PolyPolygon& rPolyPoly,
                                              sal_uInt16 nTransparencePercent )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     bool bDrawn = false;
 
@@ -607,7 +607,7 @@ void OutputDevice::EmulateDrawTransparent ( const tools::PolyPolygon& rPolyPoly,
 void OutputDevice::DrawTransparent( const tools::PolyPolygon& rPolyPoly,
                                     sal_uInt16 nTransparencePercent )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     // short circuit for drawing an opaque polygon
     if( (nTransparencePercent < 1) || (mnDrawMode & DrawModeFlags::NoTransparency) )
@@ -659,7 +659,7 @@ void OutputDevice::DrawTransparent( const tools::PolyPolygon& rPolyPoly,
 void OutputDevice::DrawTransparent( const GDIMetaFile& rMtf, const Point& rPos,
                                     const Size& rSize, const Gradient& rTransparenceGradient )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     const Color aBlack( COL_BLACK );
 
diff --git a/vcl/source/outdev/wallpaper.cxx b/vcl/source/outdev/wallpaper.cxx
index c9f3c4c02db1..367eceae7f7e 100644
--- a/vcl/source/outdev/wallpaper.cxx
+++ b/vcl/source/outdev/wallpaper.cxx
@@ -26,7 +26,7 @@
 void OutputDevice::DrawWallpaper( const Rectangle& rRect,
                                   const Wallpaper& rWallpaper )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if ( mpMetaFile )
         mpMetaFile->AddAction( new MetaWallpaperAction( rRect, rWallpaper ) );
@@ -54,7 +54,7 @@ void OutputDevice::DrawWallpaper( long nX, long nY,
                                   long nWidth, long nHeight,
                                   const Wallpaper& rWallpaper )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     if( rWallpaper.IsBitmap() )
         DrawBitmapWallpaper( nX, nY, nWidth, nHeight, rWallpaper );
@@ -68,7 +68,7 @@ void OutputDevice::DrawColorWallpaper( long nX, long nY,
                                        long nWidth, long nHeight,
                                        const Wallpaper& rWallpaper )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     // draw wallpaper without border
     Color aOldLineColor = GetLineColor();
@@ -107,7 +107,7 @@ void OutputDevice::DrawBitmapWallpaper( long nX, long nY,
                                             long nWidth, long nHeight,
                                             const Wallpaper& rWallpaper )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     BitmapEx aBmpEx;
     const BitmapEx* pCached = rWallpaper.ImplGetImpWallpaper()->ImplGetCachedBitmap();
@@ -345,7 +345,7 @@ void OutputDevice::DrawGradientWallpaper( long nX, long nY,
                                           long nWidth, long nHeight,
                                           const Wallpaper& rWallpaper )
 {
-    assert(!dynamic_cast<vcl::Window*>(this) || !dynamic_cast<vcl::Window*>(this)->SupportsDoubleBuffering());
+    assert_if_double_buffered_window();
 
     Rectangle aBound;
     GDIMetaFile* pOldMetaFile = mpMetaFile;