source/gdi/alpha.cxx

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 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
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// MARKER(update_precomp.py): autogen include statement, do not remove
#include "precompiled_vcl.hxx"
#include <tools/debug.hxx>
#include <vcl/bmpacc.hxx>
#include <tools/color.hxx>
#include <vcl/alpha.hxx>

// -------------
// - AlphaMask -
// -------------

AlphaMask::AlphaMask()
{
}

// -----------------------------------------------------------------------------

AlphaMask::AlphaMask( const Bitmap& rBitmap ) :
	Bitmap( rBitmap )
{
	if( !!rBitmap )
		Bitmap::Convert( BMP_CONVERSION_8BIT_GREYS );
}

// -----------------------------------------------------------------------------

AlphaMask::AlphaMask( const AlphaMask& rAlphaMask ) :
	Bitmap( rAlphaMask )
{
}

// -----------------------------------------------------------------------------

AlphaMask::AlphaMask( const Size& rSizePixel, sal_uInt8* pEraseTransparency ) :
	Bitmap( rSizePixel, 8, &Bitmap::GetGreyPalette( 256 ) )
{
	if( pEraseTransparency )
		Bitmap::Erase( Color( *pEraseTransparency, *pEraseTransparency, *pEraseTransparency ) );
}

// -----------------------------------------------------------------------------

AlphaMask::~AlphaMask()
{
}

// -----------------------------------------------------------------------------

AlphaMask& AlphaMask::operator=( const Bitmap& rBitmap )
{
	*(Bitmap*) this = rBitmap;

	if( !!rBitmap )
		Bitmap::Convert( BMP_CONVERSION_8BIT_GREYS );

	return *this;
}

// -----------------------------------------------------------------------------

const Bitmap& AlphaMask::ImplGetBitmap() const
{
	return( (const Bitmap&) *this );
}

// -----------------------------------------------------------------------------

void AlphaMask::ImplSetBitmap( const Bitmap& rBitmap )
{
    DBG_ASSERT( ( 8 == rBitmap.GetBitCount() ) && rBitmap.HasGreyPalette(), "AlphaMask::ImplSetBitmap: invalid bitmap" );
	*(Bitmap*) this = rBitmap;
}

// -----------------------------------------------------------------------------

Bitmap AlphaMask::GetBitmap() const
{
	return ImplGetBitmap();
}

// -----------------------------------------------------------------------------

sal_Bool AlphaMask::Crop( const Rectangle& rRectPixel )
{
	return Bitmap::Crop( rRectPixel );
}

// -----------------------------------------------------------------------------

sal_Bool AlphaMask::Expand( sal_uLong nDX, sal_uLong nDY, sal_uInt8* pInitTransparency )
{
	Color aColor;

	if( pInitTransparency )
		aColor = Color( *pInitTransparency, *pInitTransparency, *pInitTransparency );

	return Bitmap::Expand( nDX, nDY, pInitTransparency ? &aColor : NULL );
}

// -----------------------------------------------------------------------------

sal_Bool AlphaMask::CopyPixel( const Rectangle& rRectDst, const Rectangle& rRectSrc,
						   const AlphaMask* pAlphaSrc )
{
    // Note: this code is copied from Bitmap::CopyPixel but avoids any palette lookups
    // this optimization is possible because the palettes of AlphaMasks are always identical (8bit GreyPalette, see ctor)

	const Size	aSizePix( GetSizePixel() );
	Rectangle	aRectDst( rRectDst );
	sal_Bool		bRet = sal_False;

	aRectDst.Intersection( Rectangle( Point(), aSizePix ) );

	if( !aRectDst.IsEmpty() )
	{
		if( pAlphaSrc && ( *pAlphaSrc != *this ) )
		{
			Bitmap* 		pSrc = (Bitmap*) pAlphaSrc;
			const Size		aCopySizePix( pSrc->GetSizePixel() );
			Rectangle		aRectSrc( rRectSrc );

			aRectSrc.Intersection( Rectangle( Point(), aCopySizePix ) );

			if( !aRectSrc.IsEmpty() )
			{
				BitmapReadAccess* pReadAcc = pSrc->AcquireReadAccess();

				if( pReadAcc )
				{
					BitmapWriteAccess* pWriteAcc = AcquireWriteAccess();

					if( pWriteAcc )
					{
						const long	nWidth = Min( aRectSrc.GetWidth(), aRectDst.GetWidth() );
						const long	nHeight = Min( aRectSrc.GetHeight(), aRectDst.GetHeight() );
						const long	nSrcEndX = aRectSrc.Left() + nWidth;
						const long	nSrcEndY = aRectSrc.Top() + nHeight;
						long		nDstY = aRectDst.Top();

						for( long nSrcY = aRectSrc.Top(); nSrcY < nSrcEndY; nSrcY++, nDstY++ )
							for( long nSrcX = aRectSrc.Left(), nDstX = aRectDst.Left(); nSrcX < nSrcEndX; nSrcX++, nDstX++ )
								pWriteAcc->SetPixel( nDstY, nDstX, pReadAcc->GetPixel( nSrcY, nSrcX ) );

						ReleaseAccess( pWriteAcc );
						bRet = ( nWidth > 0L ) && ( nHeight > 0L );
					}

					pSrc->ReleaseAccess( pReadAcc );
				}
			}
		}
		else
		{
			Rectangle aRectSrc( rRectSrc );

			aRectSrc.Intersection( Rectangle( Point(), aSizePix ) );

			if( !aRectSrc.IsEmpty() && ( aRectSrc != aRectDst ) )
			{
				BitmapWriteAccess*	pWriteAcc = AcquireWriteAccess();

				if( pWriteAcc )
				{
					const long	nWidth = Min( aRectSrc.GetWidth(), aRectDst.GetWidth() );
					const long	nHeight = Min( aRectSrc.GetHeight(), aRectDst.GetHeight() );
					const long	nSrcX = aRectSrc.Left();
					const long	nSrcY = aRectSrc.Top();
					const long	nSrcEndX1 = nSrcX + nWidth - 1L;
					const long	nSrcEndY1 = nSrcY + nHeight - 1L;
					const long	nDstX = aRectDst.Left();
					const long	nDstY = aRectDst.Top();
					const long	nDstEndX1 = nDstX + nWidth - 1L;
					const long	nDstEndY1 = nDstY + nHeight - 1L;

					if( ( nDstX <= nSrcX ) && ( nDstY <= nSrcY ) )
					{
						for( long nY = nSrcY, nYN = nDstY; nY <= nSrcEndY1; nY++, nYN++ )
							for( long nX = nSrcX, nXN = nDstX; nX <= nSrcEndX1; nX++, nXN++ )
								pWriteAcc->SetPixel( nYN, nXN, pWriteAcc->GetPixel( nY, nX ) );
					}
					else if( ( nDstX <= nSrcX ) && ( nDstY >= nSrcY ) )
					{
						for( long nY = nSrcEndY1, nYN = nDstEndY1; nY >= nSrcY; nY--, nYN-- )
							for( long nX = nSrcX, nXN = nDstX; nX <= nSrcEndX1; nX++, nXN++ )
								pWriteAcc->SetPixel( nYN, nXN, pWriteAcc->GetPixel( nY, nX ) );
					}
					else if( ( nDstX >= nSrcX ) && ( nDstY <= nSrcY ) )
					{
						for( long nY = nSrcY, nYN = nDstY; nY <= nSrcEndY1; nY++, nYN++ )
							for( long nX = nSrcEndX1, nXN = nDstEndX1; nX >= nSrcX; nX--, nXN-- )
								pWriteAcc->SetPixel( nYN, nXN, pWriteAcc->GetPixel( nY, nX ) );
					}
					else
					{
						for( long nY = nSrcEndY1, nYN = nDstEndY1; nY >= nSrcY; nY--, nYN-- )
							for( long nX = nSrcEndX1, nXN = nDstEndX1; nX >= nSrcX; nX--, nXN-- )
								pWriteAcc->SetPixel( nYN, nXN, pWriteAcc->GetPixel( nY, nX ) );
					}

					ReleaseAccess( pWriteAcc );
					bRet = sal_True;
				}
			}
		}
	}

	return bRet;

}

// -----------------------------------------------------------------------------

sal_Bool AlphaMask::Erase( sal_uInt8 cTransparency )
{
	return Bitmap::Erase( Color( cTransparency, cTransparency, cTransparency ) );
}

// -----------------------------------------------------------------------------

sal_Bool AlphaMask::Invert()
{
	BitmapWriteAccess*	pAcc = AcquireWriteAccess();
	sal_Bool				bRet = sal_False;

	if( pAcc && pAcc->GetBitCount() == 8 )
	{
		BitmapColor	aCol( 0 );
		const long	nWidth = pAcc->Width(),	nHeight = pAcc->Height();
		sal_uInt8*		pMap = new sal_uInt8[ 256 ];

		for( long i = 0; i < 256; i++ )
			pMap[ i ] = ~(sal_uInt8) i;

		for( long nY = 0L; nY < nHeight; nY++ )
		{
			for( long nX = 0L; nX < nWidth; nX++ )
			{
				aCol.SetIndex( pMap[ pAcc->GetPixel( nY, nX ).GetIndex() ] );
				pAcc->SetPixel( nY, nX, aCol );
			}
		}

		delete[] pMap;
		bRet = sal_True;
	}

	if( pAcc )
		ReleaseAccess( pAcc );

	return bRet;
}

// -----------------------------------------------------------------------------

sal_Bool AlphaMask::Mirror( sal_uLong nMirrorFlags )
{
	return Bitmap::Mirror( nMirrorFlags );
}

// -----------------------------------------------------------------------------

sal_Bool AlphaMask::Scale( const Size& rNewSize, sal_uLong nScaleFlag )
{
	sal_Bool bRet = Bitmap::Scale( rNewSize, nScaleFlag );

	if( bRet && ( nScaleFlag == BMP_SCALE_INTERPOLATE ) )
		Bitmap::Convert( BMP_CONVERSION_8BIT_GREYS );

	return bRet;
}

// -----------------------------------------------------------------------------

sal_Bool AlphaMask::Scale( const double& rScaleX, const double& rScaleY, sal_uLong nScaleFlag )
{
	sal_Bool bRet = Bitmap::Scale( rScaleX, rScaleY, nScaleFlag );

	if( bRet && ( nScaleFlag == BMP_SCALE_INTERPOLATE ) )
		Bitmap::Convert( BMP_CONVERSION_8BIT_GREYS );

	return bRet;
}

// -----------------------------------------------------------------------------

sal_Bool AlphaMask::Rotate( long nAngle10, sal_uInt8 cFillTransparency )
{
	return Bitmap::Rotate( nAngle10, Color( cFillTransparency, cFillTransparency, cFillTransparency ) );
}

// -----------------------------------------------------------------------------

sal_Bool AlphaMask::Replace( const Bitmap& rMask, sal_uInt8 cReplaceTransparency )
{
	BitmapReadAccess*	pMaskAcc = ( (Bitmap&) rMask ).AcquireReadAccess();
	BitmapWriteAccess*	pAcc = AcquireWriteAccess();
	sal_Bool				bRet = sal_False;

	if( pMaskAcc && pAcc )
	{
		const BitmapColor	aReplace( cReplaceTransparency );
		const long			nWidth = Min( pMaskAcc->Width(), pAcc->Width() );
		const long			nHeight = Min( pMaskAcc->Height(), pAcc->Height() );
		const BitmapColor	aMaskWhite( pMaskAcc->GetBestMatchingColor( Color( COL_WHITE ) ) );

		for( long nY = 0L; nY < nHeight; nY++ )
			for( long nX = 0L; nX < nWidth; nX++ )
				if( pMaskAcc->GetPixel( nY, nX ) == aMaskWhite )
					pAcc->SetPixel( nY, nX, aReplace );
	}

	( (Bitmap&) rMask ).ReleaseAccess( pMaskAcc );
	ReleaseAccess( pAcc );

	return bRet;
}

// -----------------------------------------------------------------------------

sal_Bool AlphaMask::Replace( sal_uInt8 cSearchTransparency, sal_uInt8 cReplaceTransparency, sal_uLong
#ifdef DBG_UTIL
nTol
#endif
)
{
	BitmapWriteAccess*	pAcc = AcquireWriteAccess();
	sal_Bool				bRet = sal_False;

	DBG_ASSERT( !nTol, "AlphaMask::Replace: nTol not used yet" );

	if( pAcc && pAcc->GetBitCount() == 8 )
	{
		const long nWidth = pAcc->Width(), nHeight = pAcc->Height();

		if( pAcc->GetScanlineFormat() == BMP_FORMAT_8BIT_PAL )
		{
			for( long nY = 0L; nY < nHeight; nY++ )
			{
				Scanline pScan = pAcc->GetScanline( nY );

				for( long nX = 0L; nX < nWidth; nX++, pScan++ )
				{
					if( *pScan == cSearchTransparency )
						*pScan = cReplaceTransparency;
				}
			}
		}
		else
		{
			BitmapColor	aReplace( cReplaceTransparency );

			for( long nY = 0L; nY < nHeight; nY++ )
			{
				for( long nX = 0L; nX < nWidth; nX++ )
				{
					if( pAcc->GetPixel( nY, nX ).GetIndex() == cSearchTransparency )
						pAcc->SetPixel( nY, nX, aReplace );
				}
			}
		}

		bRet = sal_True;
	}

	if( pAcc )
		ReleaseAccess( pAcc );

	return bRet;
}

// -----------------------------------------------------------------------------

sal_Bool AlphaMask::Replace( sal_uInt8* pSearchTransparencies, sal_uInt8* pReplaceTransparencies,
						 sal_uLong nColorCount, sal_uLong* pTols )
{
	Color*	pSearchColors = new Color[ nColorCount ];
	Color*	pReplaceColors = new Color[ nColorCount ];
	sal_Bool	bRet;

	for( sal_uLong i = 0; i < nColorCount; i++ )
	{
		const sal_uInt8 cSearchTransparency = pSearchTransparencies[ i ];
		const sal_uInt8 cReplaceTransparency = pReplaceTransparencies[ i ];

		pSearchColors[ i ] = Color( cSearchTransparency, cSearchTransparency, cSearchTransparency );
		pReplaceColors[ i ] = Color( cReplaceTransparency, cReplaceTransparency, cReplaceTransparency );
	}

	bRet = Bitmap::Replace( pSearchColors, pReplaceColors, nColorCount, pTols ) &&
		   Bitmap::Convert( BMP_CONVERSION_8BIT_GREYS );

	delete[] pSearchColors;
	delete[] pReplaceColors;

	return bRet;
}

// -----------------------------------------------------------------------------

void AlphaMask::ReleaseAccess( BitmapReadAccess* pAccess )
{
	if( pAccess )
	{
		Bitmap::ReleaseAccess( pAccess );
		Bitmap::Convert( BMP_CONVERSION_8BIT_GREYS );
	}
}