include/vcl/alpha.hxx

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  19
  20 #ifndef INCLUDED_VCL_ALPHA_HXX
  21 #define INCLUDED_VCL_ALPHA_HXX
  22
  23 #include <sal/config.h>
  24
  25 #include <utility>
  26
  27 #include <vcl/dllapi.h>
  28 #include <vcl/bitmap.hxx>
  29
  30 class BitmapEx;
  31
  32 class VCL_DLLPUBLIC AlphaMask final : public Bitmap
  33 {
  34 public:
  35
  36                 AlphaMask();
  37     explicit    AlphaMask( const Bitmap& rBitmap );
  38                 AlphaMask( const AlphaMask& rAlphaMask );
  39                 AlphaMask( AlphaMask&& rAlphaMask );
  40     explicit    AlphaMask( const Size& rSizePixel, const sal_uInt8* pEraseTransparency = nullptr );
  41     virtual     ~AlphaMask() override;
  42
  43     AlphaMask&  operator=( const Bitmap& rBitmap );
  44     AlphaMask&  operator=( const AlphaMask& rAlphaMask ) { return static_cast<AlphaMask&>( Bitmap::operator=( rAlphaMask ) ); }
  45     AlphaMask&  operator=( AlphaMask&& rAlphaMask ) noexcept { return static_cast<AlphaMask&>( Bitmap::operator=( std::move(rAlphaMask) ) ); }
  46     bool        operator==( const AlphaMask& rAlphaMask ) const { return Bitmap::operator==(rAlphaMask); }
  47     bool        operator!=( const AlphaMask& rAlphaMask ) const { return Bitmap::operator!=(rAlphaMask); }
  48
  49     Bitmap const & GetBitmap() const;
  50
  51     void        Erase( sal_uInt8 cTransparency );
  52     void        BlendWith(const Bitmap& rOther);
  53
  54     // check if alpha is used, returns true if at least one pixel has transparence
  55     bool        hasAlpha() const;
  56
  57     BitmapReadAccess*  AcquireAlphaReadAccess() { return Bitmap::AcquireReadAccess(); }
  58     BitmapWriteAccess* AcquireAlphaWriteAccess() { return Bitmap::AcquireWriteAccess(); }
  59
  60     void        ReleaseAccess( BitmapReadAccess* pAccess );
  61
  62     typedef vcl::ScopedBitmapAccess<BitmapReadAccess, AlphaMask, &AlphaMask::AcquireAlphaReadAccess> ScopedReadAccess;
  63
  64     using Bitmap::IsEmpty;
  65
  66 private:
  67     friend class BitmapEx;
  68     friend class ::OutputDevice;
  69     friend bool VCL_DLLPUBLIC ReadDIBBitmapEx(BitmapEx& rTarget, SvStream& rIStm, bool bFileHeader, bool bMSOFormat);
  70
  71     SAL_DLLPRIVATE const Bitmap&    ImplGetBitmap() const;
  72     SAL_DLLPRIVATE void             ImplSetBitmap( const Bitmap& rBitmap );
  73
  74 };
  75
  76 #endif // INCLUDED_VCL_ALPHA_HXX
  77
  78 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */