From 4678c8d368c3accd85c57745cf58218f5ea1b907 Mon Sep 17 00:00:00 2001

From: Miklos Vajna <vmiklos@collabora.co.uk>

Date: Thu, 1 Oct 2015 14:17:21 +0200

Subject: [PATCH 168/398] desktop, vcl: support transparency in VirtualDevices

 with user-provided memory

Change-Id: I65c31995c02a644aa436aecd065255fab38045e4

(cherry picked from commit 1d3b613318654ceb2d34996ef8ca653cfe32a8ea)

---

 desktop/source/lib/init.cxx | 24 +++++++++++++++++++++++-

 include/vcl/virdev.hxx      |  2 ++

 vcl/source/gdi/virdev.cxx   | 12 ++++++++----

 3 files changed, 33 insertions(+), 5 deletions(-)

diff --git a/desktop/source/lib/init.cxx b/desktop/source/lib/init.cxx

index 4432ec8ea889..1f87146bacf8 100644

--- a/desktop/source/lib/init.cxx

+++ b/desktop/source/lib/init.cxx

@@ -754,10 +754,21 @@ void doc_paintTile (LibreOfficeKitDocument* pThis,

     InitSvpForLibreOfficeKit();

     ScopedVclPtrInstance< VirtualDevice > pDevice(nullptr, Size(1, 1), (sal_uInt16)32) ;

+

+    // Set background to transparent by default.

+    memset(pBuffer, 0, nCanvasWidth * nCanvasHeight * 4);

+    pDevice->SetBackground(Wallpaper(Color(COL_TRANSPARENT)));

+

     boost::shared_array< sal_uInt8 > aBuffer( pBuffer, NoDelete< sal_uInt8 >() );

+

+    // Allocate a separate buffer for the alpha device.

+    std::vector<sal_uInt8> aAlpha(nCanvasWidth * nCanvasHeight);

+    memset(aAlpha.data(), 0, nCanvasWidth * nCanvasHeight);

+    boost::shared_array<sal_uInt8> aAlphaBuffer(aAlpha.data(), NoDelete<sal_uInt8>());

+

     pDevice->SetOutputSizePixelScaleOffsetAndBuffer(

                 Size(nCanvasWidth, nCanvasHeight), Fraction(1.0), Point(),

-                aBuffer, true );

+                aBuffer, aAlphaBuffer, true );

     pDoc->paintTile(*pDevice.get(), nCanvasWidth, nCanvasHeight,

                     nTilePosX, nTilePosY, nTileWidth, nTileHeight);

@@ -771,6 +782,17 @@ void doc_paintTile (LibreOfficeKitDocument* pThis,

                     nTilePosX, nTilePosY, nTileWidth, nTileHeight);

 #endif

+    // Overwrite pBuffer's alpha channel with the separate alpha buffer.

+    for (int nRow = 0; nRow < nCanvasHeight; ++nRow)

+    {

+        for (int nCol = 0; nCol < nCanvasWidth; ++nCol)

+        {

+            const int nOffset = (nCanvasHeight * nRow) + nCol;

+            // VCL's transparent is 0, RGBA's transparent is 0xff.

+            pBuffer[nOffset * 4 +3] = 0xff - aAlpha[nOffset];

+        }

+    }

+

     static bool bDebug = getenv("LOK_DEBUG") != 0;

     if (bDebug)

     {

diff --git a/include/vcl/virdev.hxx b/include/vcl/virdev.hxx

index 3720a19c98f3..85e0afd78131 100644

--- a/include/vcl/virdev.hxx

+++ b/include/vcl/virdev.hxx

@@ -48,6 +48,7 @@ private:

                                                      const bool bTopDown );

     SAL_DLLPRIVATE bool ImplSetOutputSizePixel( const Size& rNewSize, bool bErase,

                                                 const basebmp::RawMemorySharedArray &pBuffer,

+                                                const basebmp::RawMemorySharedArray &pAlphaBuffer,

                                                 const bool bTopDown );

     VirtualDevice (const VirtualDevice &) SAL_DELETED_FUNCTION;

@@ -127,6 +128,7 @@ public:

                                                                 const Fraction& rScale,

                                                                 const Point& rNewOffset,

                                                                 const basebmp::RawMemorySharedArray &pBuffer,

+                                                                const basebmp::RawMemorySharedArray &pAlphaBuffer,

                                                                 const bool bTopDown = false );

     bool                SetOutputSize( const Size& rNewSize, bool bErase = true )

                             { return SetOutputSizePixel( LogicToPixel( rNewSize ), bErase ); }

diff --git a/vcl/source/gdi/virdev.cxx b/vcl/source/gdi/virdev.cxx

index b24378de4b25..ee44d30267e8 100644

--- a/vcl/source/gdi/virdev.cxx

+++ b/vcl/source/gdi/virdev.cxx

@@ -393,6 +393,7 @@ void VirtualDevice::ImplFillOpaqueRectangle( const Rectangle& rRect )

 bool VirtualDevice::ImplSetOutputSizePixel( const Size& rNewSize, bool bErase,

                                             const basebmp::RawMemorySharedArray &pBuffer,

+                                            const basebmp::RawMemorySharedArray &pAlphaBuffer,

                                             const bool bTopDown )

 {

     if( InnerImplSetOutputSizePixel(rNewSize, bErase, pBuffer, bTopDown) )

@@ -409,7 +410,7 @@ bool VirtualDevice::ImplSetOutputSizePixel( const Size& rNewSize, bool bErase,

             {

                 mpAlphaVDev = VclPtr<VirtualDevice>::Create( *this, mnAlphaDepth );

                 mpAlphaVDev->InnerImplSetOutputSizePixel(rNewSize, bErase,

-                                                         basebmp::RawMemorySharedArray(),

+                                                         pAlphaBuffer,

                                                          bTopDown );

             }

@@ -443,13 +444,16 @@ void VirtualDevice::EnableRTL( bool bEnable )

 bool VirtualDevice::SetOutputSizePixel( const Size& rNewSize, bool bErase )

 {

-    return ImplSetOutputSizePixel( rNewSize, bErase, basebmp::RawMemorySharedArray(), false );

+    return ImplSetOutputSizePixel( rNewSize, bErase, basebmp::RawMemorySharedArray(), basebmp::RawMemorySharedArray(), false );

 }

 bool VirtualDevice::SetOutputSizePixelScaleOffsetAndBuffer(

     const Size& rNewSize, const Fraction& rScale, const Point& rNewOffset,

-    const basebmp::RawMemorySharedArray &pBuffer, const bool bTopDown )

+    const basebmp::RawMemorySharedArray &pBuffer, const basebmp::RawMemorySharedArray &pAlphaBuffer, const bool bTopDown )

 {

+    if (pAlphaBuffer)

+        mnAlphaDepth = 8;

+

     if (pBuffer) {

         MapMode mm = GetMapMode();

         mm.SetOrigin( rNewOffset );

@@ -457,7 +461,7 @@ bool VirtualDevice::SetOutputSizePixelScaleOffsetAndBuffer(

         mm.SetScaleY( rScale );

         SetMapMode( mm );

     }

-    return ImplSetOutputSizePixel( rNewSize, true, pBuffer, bTopDown );

+    return ImplSetOutputSizePixel( rNewSize, true, pBuffer, pAlphaBuffer, bTopDown );

 }

 void VirtualDevice::SetReferenceDevice( RefDevMode i_eRefDevMode )

-- 

2.12.0