Wrap CGLayer into a CGLayerHolder class and move code to use it

Change-Id: I52539f6582d099ef80048d9a25266c88e1f6d783
Reviewed-on: https://gerrit.libreoffice.org/72439
Tested-by: Jenkins
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>

5 files changed, 85 insertions, 88 deletions

diff --git a/vcl/quartz/salbmp.cxx b/vcl/quartz/salbmp.cxx
index 12daa7567f42..745b57bd82a9 100644
--- a/vcl/quartz/salbmp.cxx
+++ b/vcl/quartz/salbmp.cxx
@@ -69,10 +69,9 @@ QuartzSalBitmap::~QuartzSalBitmap()
     Destroy();
 }
 
-bool QuartzSalBitmap::Create( CGLayerRef xLayer, int nBitmapBits,
-    int nX, int nY, int nWidth, int nHeight, bool bFlipped )
+bool QuartzSalBitmap::Create(CGLayerHolder const & rLayerHolder, int nBitmapBits, int nX, int nY, int nWidth, int nHeight, bool bFlipped)
 {
-    SAL_WARN_IF( !xLayer, "vcl", "QuartzSalBitmap::Create() from non-layered context" );
+    SAL_WARN_IF(!rLayerHolder.isSet(), "vcl", "QuartzSalBitmap::Create() from non-layered context");
 
     // sanitize input parameters
     if( nX < 0 ) {
@@ -85,8 +84,8 @@ bool QuartzSalBitmap::Create( CGLayerRef xLayer, int nBitmapBits,
         nY = 0;
     }
 
-    const CGSize aLayerSize = CGLayerGetSize( xLayer );
-    SAL_INFO("vcl.cg", "CGLayerGetSize(" << xLayer << ") = " << aLayerSize );
+    const CGSize aLayerSize = CGLayerGetSize(rLayerHolder.get());
+    SAL_INFO("vcl.cg", "CGLayerGetSize(" << rLayerHolder.get() << ") = " << aLayerSize );
     if( nWidth >= static_cast<int>(aLayerSize.width) - nX )
         nWidth = static_cast<int>(aLayerSize.width) - nX;
 
@@ -108,7 +107,7 @@ bool QuartzSalBitmap::Create( CGLayerRef xLayer, int nBitmapBits,
     const CGPoint aSrcPoint = { static_cast<CGFloat>(-nX), static_cast<CGFloat>(-nY) };
     if(mxGraphicContext) // remove warning
     {
-        SAL_INFO("vcl.cg", "CGContextDrawLayerAtPoint(" << mxGraphicContext << "," << aSrcPoint << "," << xLayer << ")" );
+        SAL_INFO("vcl.cg", "CGContextDrawLayerAtPoint(" << mxGraphicContext << "," << aSrcPoint << "," << rLayerHolder.get() << ")" );
         if( bFlipped )
         {
             SAL_INFO( "vcl.cg", "CGContextTranslateCTM(" << mxGraphicContext << ",0," << mnHeight << ")" );
@@ -117,7 +116,7 @@ bool QuartzSalBitmap::Create( CGLayerRef xLayer, int nBitmapBits,
             CGContextScaleCTM( mxGraphicContext, +1, -1 );
         }
 
-        CGContextDrawLayerAtPoint( mxGraphicContext, aSrcPoint, xLayer );
+        CGContextDrawLayerAtPoint( mxGraphicContext, aSrcPoint, rLayerHolder.get() );
     }
     return true;
 }
diff --git a/vcl/quartz/salgdi.cxx b/vcl/quartz/salgdi.cxx
index a68f9e9736ef..846b7abbbc49 100644
--- a/vcl/quartz/salgdi.cxx
+++ b/vcl/quartz/salgdi.cxx
@@ -181,11 +181,7 @@ bool CoreTextFontFace::GetFontCapabilities(vcl::FontCapabilities &rFontCapabilit
 }
 
 AquaSalGraphics::AquaSalGraphics()
-    : mxLayer( nullptr )
-#ifdef MACOSX
-    , mpFrame( nullptr )
-#endif
-    , mpXorEmulation( nullptr )
+    : mpXorEmulation( nullptr )
     , mnXorMode( 0 )
     , mnWidth( 0 )
     , mnHeight( 0 )
@@ -197,6 +193,9 @@ AquaSalGraphics::AquaSalGraphics()
     , maFillColor( COL_BLACK )
     , maTextColor( COL_BLACK )
     , mbNonAntialiasedText( false )
+#ifdef MACOSX
+    , mpFrame( nullptr )
+#endif
     , mbPrinter( false )
     , mbVirDev( false )
 #ifdef MACOSX
@@ -238,10 +237,10 @@ AquaSalGraphics::~AquaSalGraphics()
     if (mbForeignContext)
         return;
 #endif
-    if( mxLayer )
+    if (maLayer.isSet())
     {
-        SAL_INFO("vcl.cg", "CGLayerRelease(" << mxLayer << ")" );
-        CGLayerRelease( mxLayer );
+        SAL_INFO("vcl.cg", "CGLayerRelease(" << maLayer.get() << ")" );
+        CGLayerRelease(maLayer.get());
     }
     else if (maContextHolder.isSet()
 #ifdef MACOSX
diff --git a/vcl/quartz/salgdicommon.cxx b/vcl/quartz/salgdicommon.cxx
index dc73d3c95b28..11fc42fc6cfc 100644
--- a/vcl/quartz/salgdicommon.cxx
+++ b/vcl/quartz/salgdicommon.cxx
@@ -347,14 +347,14 @@ void AquaSalGraphics::copyBits( const SalTwoRect& rPosAry, SalGraphics *pSrcGrap
     ApplyXorContext();
     pSrc->ApplyXorContext();
 
-    SAL_WARN_IF( !pSrc->mxLayer, "vcl.quartz",
-                 "AquaSalGraphics::copyBits() from non-layered graphics this=" << this );
+    SAL_WARN_IF (!pSrc->maLayer.isSet(), "vcl.quartz",
+                 "AquaSalGraphics::copyBits() from non-layered graphics this=" << this);
 
     const CGPoint aDstPoint = CGPointMake(+rPosAry.mnDestX - rPosAry.mnSrcX, rPosAry.mnDestY - rPosAry.mnSrcY);
-    if( (rPosAry.mnSrcWidth == rPosAry.mnDestWidth &&
+    if ((rPosAry.mnSrcWidth == rPosAry.mnDestWidth &&
          rPosAry.mnSrcHeight == rPosAry.mnDestHeight) &&
         (!mnBitmapDepth || (aDstPoint.x + pSrc->mnWidth) <= mnWidth)
-        && pSrc->mxLayer ) // workaround for a Quartz crash
+        && pSrc->maLayer.isSet()) // workaround for a Quartz crash
     {
         // in XOR mode the drawing context is redirected to the XOR mask
         // if source and target are identical then copyBits() paints onto the target context though
@@ -384,8 +384,8 @@ void AquaSalGraphics::copyBits( const SalTwoRect& rPosAry, SalGraphics *pSrcGrap
         }
 
         // TODO: pSrc->size() != this->size()
-        SAL_INFO( "vcl.cg", "CGContextDrawLayerAtPoint(" << xCopyContext << "," << aDstPoint << "," << pSrc->mxLayer << ")" );
-        CGContextDrawLayerAtPoint( xCopyContext, aDstPoint, pSrc->mxLayer );
+        SAL_INFO( "vcl.cg", "CGContextDrawLayerAtPoint(" << xCopyContext << "," << aDstPoint << "," << pSrc->maLayer.get() << ")");
+        CGContextDrawLayerAtPoint(xCopyContext, aDstPoint, pSrc->maLayer.get());
 
         SAL_INFO( "vcl.cg", "CGContextRestoreGState(" << xCopyContext << ")" );
         CGContextRestoreGState( xCopyContext );
@@ -478,11 +478,11 @@ void AquaSalGraphics::ApplyXorContext()
 void AquaSalGraphics::copyArea( long nDstX, long nDstY,long nSrcX, long nSrcY,
                                 long nSrcWidth, long nSrcHeight, bool /*bWindowInvalidate*/ )
 {
-    SAL_WARN_IF( !mxLayer, "vcl.quartz",
-                 "AquaSalGraphics::copyArea() for non-layered graphics this=" << this );
+    SAL_WARN_IF (!maLayer.isSet(), "vcl.quartz",
+                 "AquaSalGraphics::copyArea() for non-layered graphics this=" << this);
 
 #ifdef IOS
-    if( !mxLayer )
+    if (!maLayer.isSet())
         return;
 #endif
 
@@ -500,15 +500,15 @@ void AquaSalGraphics::copyArea( long nDstX, long nDstY,long nSrcX, long nSrcY,
     //       e.g. on OSX>=10.5 only this situation causes problems:
     //          mnBitmapDepth && (aDstPoint.x + pSrc->mnWidth) > mnWidth
 
-    CGLayerRef xSrcLayer = mxLayer;
+    CGLayerHolder sSourceLayerHolder(maLayer.get());
     // TODO: if( mnBitmapDepth > 0 )
     {
         const CGSize aSrcSize = CGSizeMake(nSrcWidth, nSrcHeight);
-        xSrcLayer = CGLayerCreateWithContext( xCopyContext, aSrcSize, nullptr );
-        SAL_INFO( "vcl.cg", "CGLayerCreateWithContext(" << xCopyContext << "," << aSrcSize << ",NULL) = " << xSrcLayer );
+        sSourceLayerHolder.set(CGLayerCreateWithContext(xCopyContext, aSrcSize, nullptr));
+        SAL_INFO( "vcl.cg", "CGLayerCreateWithContext(" << xCopyContext << "," << aSrcSize << ",NULL) = " << sSourceLayerHolder.get());
 
-        const CGContextRef xSrcContext = CGLayerGetContext( xSrcLayer );
-        SAL_INFO( "vcl.cg", "CGLayerGetContext(" << xSrcLayer << ") = " << xSrcContext );
+        const CGContextRef xSrcContext = CGLayerGetContext(sSourceLayerHolder.get());
+        SAL_INFO( "vcl.cg", "CGLayerGetContext(" << sSourceLayerHolder.get() << ") = " << xSrcContext);
 
         CGPoint aSrcPoint = CGPointMake(-nSrcX, -nSrcY);
         if( IsFlipped() )
@@ -519,20 +519,20 @@ void AquaSalGraphics::copyArea( long nDstX, long nDstY,long nSrcX, long nSrcY,
             CGContextScaleCTM( xSrcContext, +1, -1 );
             aSrcPoint.y = (nSrcY + nSrcHeight) - mnHeight;
         }
-        SAL_INFO( "vcl.cg", "CGContextDrawLayerAtPoint(" << xSrcContext << "," << aSrcPoint << "," << mxLayer << ")" );
-        CGContextDrawLayerAtPoint( xSrcContext, aSrcPoint, mxLayer );
+        SAL_INFO( "vcl.cg", "CGContextDrawLayerAtPoint(" << xSrcContext << "," << aSrcPoint << "," << maLayer.get() << ")" );
+        CGContextDrawLayerAtPoint(xSrcContext, aSrcPoint, maLayer.get());
     }
 
     // draw at new destination
     const CGPoint aDstPoint = CGPointMake(+nDstX, +nDstY);
-    SAL_INFO( "vcl.cg", "CGContextDrawLayerAtPoint(" << xCopyContext << "," << aDstPoint << "," << xSrcLayer << ")" );
-    CGContextDrawLayerAtPoint( xCopyContext, aDstPoint, xSrcLayer );
+    SAL_INFO( "vcl.cg", "CGContextDrawLayerAtPoint(" << xCopyContext << "," << aDstPoint << "," << sSourceLayerHolder.get() << ")" );
+    CGContextDrawLayerAtPoint(xCopyContext, aDstPoint, sSourceLayerHolder.get());
 
     // cleanup
-    if( xSrcLayer != mxLayer )
+    if (sSourceLayerHolder.get() != maLayer.get())
     {
-        SAL_INFO( "vcl.cg", "CGLayerRelease(" << xSrcLayer << ")" );
-        CGLayerRelease( xSrcLayer );
+        SAL_INFO( "vcl.cg", "CGLayerRelease(" << sSourceLayerHolder.get() << ")" );
+        CGLayerRelease(sSourceLayerHolder.get());
     }
     // mark the destination rectangle as updated
     RefreshRect( nDstX, nDstY, nSrcWidth, nSrcHeight );
@@ -1298,12 +1298,12 @@ sal_uInt16 AquaSalGraphics::GetBitCount() const
 
 std::shared_ptr<SalBitmap> AquaSalGraphics::getBitmap( long  nX, long  nY, long  nDX, long  nDY )
 {
-    SAL_WARN_IF( !mxLayer, "vcl.quartz", "AquaSalGraphics::getBitmap() with no layer this=" << this );
+    SAL_WARN_IF(!maLayer.isSet(), "vcl.quartz", "AquaSalGraphics::getBitmap() with no layer this=" << this);
 
     ApplyXorContext();
 
     std::shared_ptr<QuartzSalBitmap> pBitmap = std::make_shared<QuartzSalBitmap>();
-    if( !pBitmap->Create( mxLayer, mnBitmapDepth, nX, nY, nDX, nDY, IsFlipped()) )
+    if (!pBitmap->Create(maLayer, mnBitmapDepth, nX, nY, nDX, nDY, IsFlipped()))
     {
         pBitmap = nullptr;
     }
@@ -1345,7 +1345,7 @@ long AquaSalGraphics::GetGraphicsWidth() const
 Color AquaSalGraphics::getPixel( long nX, long nY )
 {
     // return default value on printers or when out of bounds
-    if( !mxLayer || (nX < 0) || (nX >= mnWidth) ||
+    if (!maLayer.isSet() || (nX < 0) || (nX >= mnWidth) ||
         (nY < 0) || (nY >= mnHeight))
     {
         return sal_uInt32(COL_BLACK);
@@ -1375,9 +1375,9 @@ Color AquaSalGraphics::getPixel( long nX, long nY )
         nY = mnHeight - nY;
     }
     const CGPoint aCGPoint = CGPointMake(-nX, -nY);
-    SAL_INFO( "vcl.cg", "CGContextDrawLayerAtPoint(" <<
-              xOnePixelContext << "," << aCGPoint << "," << mxLayer << ")" );
-    CGContextDrawLayerAtPoint( xOnePixelContext, aCGPoint, mxLayer );
+    SAL_INFO("vcl.cg", "CGContextDrawLayerAtPoint(" <<
+             xOnePixelContext << "," << aCGPoint << "," << maLayer.get() << ")");
+    CGContextDrawLayerAtPoint(xOnePixelContext, aCGPoint, maLayer.get());
 
     SAL_INFO( "vcl.cg", "CGContextRelease(" << xOnePixelContext << ")" );
     CGContextRelease( xOnePixelContext );
@@ -1851,7 +1851,7 @@ void AquaSalGraphics::SetXORMode( bool bSet, bool bInvertOnly )
     if( !mpXorEmulation )
     {
         mpXorEmulation = new XorEmulation();
-        mpXorEmulation->SetTarget( mnWidth, mnHeight, mnBitmapDepth, maContextHolder.get(), mxLayer );
+        mpXorEmulation->SetTarget(mnWidth, mnHeight, mnBitmapDepth, maContextHolder.get(), maLayer.get());
     }
 
     // change the XOR mode
@@ -2056,10 +2056,10 @@ bool XorEmulation::UpdateTarget()
     return true;
 }
 
-void AquaSalGraphics::SetVirDevGraphics( CGLayerRef xLayer, CGContextRef xContext,
-    int nBitmapDepth )
+void AquaSalGraphics::SetVirDevGraphics(CGLayerHolder const & rLayer, CGContextRef xContext,
+                                        int nBitmapDepth)
 {
-    SAL_INFO( "vcl.quartz", "SetVirDevGraphics() this=" << this << " layer=" << xLayer << " context=" << xContext );
+    SAL_INFO( "vcl.quartz", "SetVirDevGraphics() this=" << this << " layer=" << rLayer.get() << " context=" << xContext );
 
 #ifndef IOS
     mbWindow = false;
@@ -2070,7 +2070,7 @@ void AquaSalGraphics::SetVirDevGraphics( CGLayerRef xLayer, CGContextRef xContex
 #ifdef IOS
     (void) nBitmapDepth;
 
-    if( !xContext )
+    if (!xContext)
     {
         // We will return early a few lines lower.
         // Undo the "stack initialization" done at the initial call of
@@ -2080,7 +2080,7 @@ void AquaSalGraphics::SetVirDevGraphics( CGLayerRef xLayer, CGContextRef xContex
 #endif
 
     // set graphics properties
-    mxLayer = xLayer;
+    maLayer = rLayer;
     maContextHolder.set(xContext);
 
 #ifndef IOS
@@ -2096,7 +2096,7 @@ void AquaSalGraphics::SetVirDevGraphics( CGLayerRef xLayer, CGContextRef xContex
         return;
 
     // get new graphics properties
-    if( !mxLayer )
+    if (!maLayer.isSet())
     {
         mnWidth = CGBitmapContextGetWidth( maContextHolder.get() );
         mnHeight = CGBitmapContextGetHeight( maContextHolder.get() );
@@ -2105,10 +2105,10 @@ void AquaSalGraphics::SetVirDevGraphics( CGLayerRef xLayer, CGContextRef xContex
     }
     else
     {
-        const CGSize aSize = CGLayerGetSize( mxLayer );
+        const CGSize aSize = CGLayerGetSize(maLayer.get());
         mnWidth = static_cast<int>(aSize.width);
         mnHeight = static_cast<int>(aSize.height);
-        SAL_INFO( "vcl.cg", "CGLayerGetSize(" << mxLayer << ") = " << aSize );
+        SAL_INFO("vcl.cg", "CGLayerGetSize(" << maLayer.get() << ") = " << aSize);
     }
 
     // prepare graphics for drawing
@@ -2119,7 +2119,7 @@ void AquaSalGraphics::SetVirDevGraphics( CGLayerRef xLayer, CGContextRef xContex
     // re-enable XorEmulation for the new context
     if( mpXorEmulation )
     {
-        mpXorEmulation->SetTarget( mnWidth, mnHeight, mnBitmapDepth, maContextHolder.get(), mxLayer );
+        mpXorEmulation->SetTarget(mnWidth, mnHeight, mnBitmapDepth, maContextHolder.get(), maLayer.get());
         if( mpXorEmulation->IsEnabled() )
         {
             maContextHolder.set(mpXorEmulation->GetMaskContext());
diff --git a/vcl/quartz/salgdiutils.cxx b/vcl/quartz/salgdiutils.cxx
index 98213b7c3344..4c13ad788183 100644
--- a/vcl/quartz/salgdiutils.cxx
+++ b/vcl/quartz/salgdiutils.cxx
@@ -88,7 +88,7 @@ void AquaSalGraphics::UnsetState()
 }
 
 /**
- * (re-)create the off-screen mxLayer we render everything to if
+ * (re-)create the off-screen maLayer we render everything to if
  * necessary: eg. not initialized yet, or it has an incorrect size.
  */
 bool AquaSalGraphics::CheckContext()
@@ -106,15 +106,15 @@ bool AquaSalGraphics::CheckContext()
             mnWidth = nWidth;
             mnHeight = nHeight;
             // prepare to release the corresponding resources
-            if (mxLayer)
-                rReleaseLayer = mxLayer;
+            if (maLayer.isSet())
+                rReleaseLayer = maLayer.get();
             else if (maContextHolder.isSet())
             {
                 SAL_INFO("vcl.cg", "CGContextRelease(" << maContextHolder.get() << ")");
                 CGContextRelease(maContextHolder.get());
             }
             maContextHolder.set(nullptr);
-            mxLayer = nullptr;
+            maLayer.set(nullptr);
         }
 
         if (!maContextHolder.isSet())
@@ -124,12 +124,12 @@ bool AquaSalGraphics::CheckContext()
                 const CGSize aLayerSize = { static_cast<CGFloat>(nWidth), static_cast<CGFloat>(nHeight) };
                 NSGraphicsContext* pNSGContext = [NSGraphicsContext graphicsContextWithWindow: mpFrame->getNSWindow()];
                 CGContextRef xCGContext = [pNSGContext CGContext];
-                mxLayer = CGLayerCreateWithContext(xCGContext, aLayerSize, nullptr);
-                SAL_INFO("vcl.cg", "CGLayerCreateWithContext(" << xCGContext << "," << aLayerSize << ",NULL) = " << mxLayer);
-                if (mxLayer)
+                maLayer.set(CGLayerCreateWithContext(xCGContext, aLayerSize, nullptr));
+                SAL_INFO("vcl.cg", "CGLayerCreateWithContext(" << xCGContext << "," << aLayerSize << ",NULL) = " << maLayer.get());
+                if (maLayer.isSet())
                 {
-                    maContextHolder.set(CGLayerGetContext(mxLayer));
-                    SAL_INFO( "vcl.cg", "CGLayerGetContext(" << mxLayer << ") = " << maContextHolder.get() );
+                    maContextHolder.set(CGLayerGetContext(maLayer.get()));
+                    SAL_INFO( "vcl.cg", "CGLayerGetContext(" << maLayer.get() << ") = " << maContextHolder.get() );
                 }
 
                 if (rReleaseLayer)
@@ -168,7 +168,7 @@ bool AquaSalGraphics::CheckContext()
 
                 // re-enable XOR emulation for the new context
                 if (mpXorEmulation)
-                    mpXorEmulation->SetTarget(mnWidth, mnHeight, mnBitmapDepth, maContextHolder.get(), mxLayer);
+                    mpXorEmulation->SetTarget(mnWidth, mnHeight, mnBitmapDepth, maContextHolder.get(), maLayer.get());
             }
         }
     }
@@ -187,7 +187,7 @@ CGContextRef AquaSalGraphics::GetContext()
 }
 
 /**
- * Blit the contents of our internal mxLayer state to the
+ * Blit the contents of our internal maLayer state to the
  * associated window, if any; cf. drawRect event handling
  * on the frame.
  */
@@ -199,7 +199,7 @@ void AquaSalGraphics::UpdateWindow( NSRect& )
     }
 
     NSGraphicsContext* pContext = [NSGraphicsContext currentContext];
-    if( (mxLayer != nullptr) && (pContext != nullptr) )
+    if (maLayer.isSet() && pContext != nullptr)
     {
         CGContextRef rCGContext = [pContext CGContext];
         SAL_INFO( "vcl.cg", "[[NSGraphicsContext currentContext] CGContext] = " << rCGContext );
@@ -217,8 +217,8 @@ void AquaSalGraphics::UpdateWindow( NSRect& )
         }
 
         ApplyXorContext();
-        SAL_INFO( "vcl.cg", "CGContextDrawLayerAtPoint(" << rCGContext << "," << CGPointZero << "," << mxLayer << ")" );
-        CGContextDrawLayerAtPoint( rCGContext, CGPointZero, mxLayer );
+        SAL_INFO( "vcl.cg", "CGContextDrawLayerAtPoint(" << rCGContext << "," << CGPointZero << "," << maLayer.get() << ")" );
+        CGContextDrawLayerAtPoint( rCGContext, CGPointZero, maLayer.get() );
         if( rClip ) // cleanup clipping
         {
             CGContextRestoreGState( rCGContext );
diff --git a/vcl/quartz/salvd.cxx b/vcl/quartz/salvd.cxx
index a08345dfd1c1..84e6c7cf992f 100644
--- a/vcl/quartz/salvd.cxx
+++ b/vcl/quartz/salvd.cxx
@@ -67,7 +67,6 @@ AquaSalVirtualDevice::AquaSalVirtualDevice( AquaSalGraphics* pGraphic, long &nDX
   : mbGraphicsUsed( false )
   , mxBitmapContext( nullptr )
   , mnBitmapDepth( 0 )
-  , mxLayer( nullptr )
   , mnWidth(0)
   , mnHeight(0)
 {
@@ -90,11 +89,11 @@ AquaSalVirtualDevice::AquaSalVirtualDevice( AquaSalGraphics* pGraphic, long &nDX
         {
             nDY = 1;
         }
-        mxLayer = CGLayerCreateWithContext( pData->rCGContext, CGSizeMake( nDX, nDY), nullptr );
+        maLayer.set(CGLayerCreateWithContext(pData->rCGContext, CGSizeMake(nDX, nDY), nullptr));
         // Interrogate the context as to its real size
-        if (mxLayer)
+        if (maLayer.isSet())
         {
-            const CGSize aSize = CGLayerGetSize( mxLayer );
+            const CGSize aSize = CGLayerGetSize(maLayer.get());
             nDX = static_cast<long>(aSize.width);
             nDY = static_cast<long>(aSize.height);
         }
@@ -104,8 +103,8 @@ AquaSalVirtualDevice::AquaSalVirtualDevice( AquaSalGraphics* pGraphic, long &nDX
             nDY = 0;
         }
         SAL_INFO( "vcl.cg",  "CGLayerCreateWithContext(" << pData->rCGContext <<
-                  "," << CGSizeMake( nDX, nDY) << ",NULL) = " << mxLayer );
-        mpGraphics->SetVirDevGraphics( mxLayer, pData->rCGContext );
+                  "," << CGSizeMake( nDX, nDY) << ",NULL) = " << maLayer.get());
+        mpGraphics->SetVirDevGraphics(maLayer, pData->rCGContext);
     }
     else
     {
@@ -166,19 +165,19 @@ void AquaSalVirtualDevice::Destroy()
     if( mbForeignContext )
     {
         // Do not delete mxContext that we have received from outside VCL
-        mxLayer = nullptr;
+        maLayer.set(nullptr);
         return;
     }
 
-    if( mxLayer )
+    if (maLayer.isSet())
     {
         if( mpGraphics )
         {
-            mpGraphics->SetVirDevGraphics( nullptr, nullptr );
+            mpGraphics->SetVirDevGraphics(nullptr, nullptr);
         }
-        SAL_INFO( "vcl.cg",  "CGLayerRelease(" << mxLayer << ")" );
-        CGLayerRelease( mxLayer );
-        mxLayer = nullptr;
+        SAL_INFO("vcl.cg",  "CGLayerRelease(" << maLayer.get() << ")");
+        CGLayerRelease(maLayer.get());
+        maLayer.set(nullptr);
     }
 
     if( mxBitmapContext )
@@ -217,10 +216,10 @@ bool AquaSalVirtualDevice::SetSize( long nDX, long nDY )
         return true;
     }
 
-    if( mxLayer )
+    if (maLayer.isSet())
     {
-        const CGSize aSize = CGLayerGetSize( mxLayer );
-        SAL_INFO( "vcl.cg",  "CGlayerGetSize(" << mxLayer << ") = " << aSize );
+        const CGSize aSize = CGLayerGetSize(maLayer.get());
+        SAL_INFO( "vcl.cg",  "CGlayerGetSize(" << maLayer.get() << ") = " << aSize );
         if( (nDX == aSize.width) && (nDY == aSize.height) )
         {
             // Yay, we do not have to do anything :)
@@ -296,18 +295,18 @@ bool AquaSalVirtualDevice::SetSize( long nDX, long nDY )
     SAL_WARN_IF( !xCGContext, "vcl.quartz", "No context" );
 
     const CGSize aNewSize = { static_cast<CGFloat>(nDX), static_cast<CGFloat>(nDY) };
-    mxLayer = CGLayerCreateWithContext( xCGContext, aNewSize, nullptr );
-    SAL_INFO( "vcl.cg",  "CGLayerCreateWithContext(" << xCGContext << "," << aNewSize << ",NULL) = " << mxLayer );
+    maLayer.set(CGLayerCreateWithContext(xCGContext, aNewSize, nullptr));
+    SAL_INFO("vcl.cg",  "CGLayerCreateWithContext(" << xCGContext << "," << aNewSize << ",NULL) = " << maLayer.get());
 
-    if( mxLayer && mpGraphics )
+    if (maLayer.isSet() && mpGraphics)
     {
         // get the matching Quartz context
-        CGContextRef xDrawContext = CGLayerGetContext( mxLayer );
-        SAL_INFO( "vcl.cg",  "CGLayerGetContext(" << mxLayer << ") = " << xDrawContext );
-        mpGraphics->SetVirDevGraphics( mxLayer, xDrawContext, mnBitmapDepth );
+        CGContextRef xDrawContext = CGLayerGetContext( maLayer.get() );
+        SAL_INFO( "vcl.cg",  "CGLayerGetContext(" << maLayer.get() << ") = " << xDrawContext );
+        mpGraphics->SetVirDevGraphics(maLayer.get(), xDrawContext, mnBitmapDepth);
     }
 
-    return (mxLayer != nullptr);
+    return maLayer.isSet();
 }
 
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */