source/gdi/atslayout.cxx

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#include "tools/debug.hxx"

#include "aqua/saldata.hxx"
#include "aqua/salgdi.h"
#include "aqua/salatsuifontutils.hxx"

#include "sallayout.hxx"
#include "salgdi.hxx"

#include <math.h>

// =======================================================================

class ATSLayout : public SalLayout
{
public:
                    ATSLayout( ATSUStyle&, float fFontScale );
	virtual         ~ATSLayout();

	virtual bool	LayoutText( ImplLayoutArgs& );
	virtual void	AdjustLayout( ImplLayoutArgs& );
	virtual void	DrawText( SalGraphics& ) const;

	virtual int		GetNextGlyphs( int nLen, sal_GlyphId* pGlyphs, Point& rPos, int&,
						sal_Int32* pGlyphAdvances, int* pCharIndexes ) const;

	virtual long    GetTextWidth() const;
	virtual long    FillDXArray( long* pDXArray ) const;
	virtual int     GetTextBreak( long nMaxWidth, long nCharExtra, int nFactor ) const;
	virtual void    GetCaretPositions( int nArraySize, long* pCaretXArray ) const;
	virtual bool    GetGlyphOutlines( SalGraphics&, PolyPolyVector& ) const;
	virtual bool    GetBoundRect( SalGraphics&, Rectangle& ) const;

	const ImplFontData* GetFallbackFontData( sal_GlyphId ) const;

	virtual void    InitFont();
	virtual void    MoveGlyph( int nStart, long nNewXPos );
	virtual void    DropGlyph( int nStart );
	virtual void    Simplify( bool bIsBase );

private:
	ATSUStyle&			mrATSUStyle;
	ATSUTextLayout		maATSULayout;
	int					mnCharCount;		// ==mnEndCharPos-mnMinCharPos
	// to prevent ATS overflowing the Fixed16.16 values
	// ATS font requests get size limited by downscaling huge fonts
	// in these cases the font scale becomes something bigger than 1.0
	float				mfFontScale;

private:
	bool	InitGIA( ImplLayoutArgs* pArgs = NULL ) const;
	bool	GetIdealX() const;
	bool	GetDeltaY() const;
	void	InvalidateMeasurements();

	int	Fixed2Vcl( Fixed ) const;       // convert ATSU-Fixed units to VCL units
	int	AtsuPix2Vcl( int ) const;       // convert ATSU-Pixel units to VCL units
	Fixed	Vcl2Fixed( int ) const;     // convert VCL units to ATSU-Fixed units

    // cached details about the resulting layout
    // mutable members since these details are all lazy initialized
    mutable int			mnGlyphCount;			// glyph count
    mutable Fixed		mnCachedWidth;			// cached value of resulting typographical width
    int					mnTrailingSpaceWidth;   // in Pixels

	mutable ATSGlyphRef*	mpGlyphIds;			// ATSU glyph ids
    mutable Fixed*			mpCharWidths;       // map relative charpos to charwidth
    mutable int*			mpChars2Glyphs;     // map relative charpos to absolute glyphpos
    mutable int*			mpGlyphs2Chars;     // map absolute glyphpos to absolute charpos
    mutable bool*			mpGlyphRTLFlags;    // BiDi status for glyphs: true if RTL
    mutable Fixed*			mpGlyphAdvances;	// contains glyph widths for the justified layout
    mutable Fixed*			mpGlyphOrigAdvs;	// contains glyph widths for the unjustified layout
    mutable Fixed*			mpDeltaY;			// vertical offset from the baseline

	struct SubPortion { int mnMinCharPos, mnEndCharPos; Fixed mnXOffset; };
	typedef std::vector<SubPortion> SubPortionVector;
	mutable SubPortionVector	maSubPortions;		// Writer&ATSUI layouts can differ quite a bit...

    // storing details about fonts used in glyph-fallback for this layout
    mutable class FallbackInfo*	mpFallbackInfo;

    // x-offset relative to layout origin
    // currently only used in RTL-layouts
    mutable Fixed			mnBaseAdv;
};

class FallbackInfo
{
public:
        FallbackInfo() : mnMaxLevel(0) {}
    int AddFallback( ATSUFontID );
    const ImplFontData* GetFallbackFontData( int nLevel ) const;

private:
    const ImplMacFontData* maFontData[ MAX_FALLBACK ];
    ATSUFontID             maATSUFontId[ MAX_FALLBACK ];
    int                    mnMaxLevel;
};

// =======================================================================

ATSLayout::ATSLayout( ATSUStyle& rATSUStyle, float fFontScale )
:   mrATSUStyle( rATSUStyle ),
	maATSULayout( NULL ),
	mnCharCount( 0 ),
	mfFontScale( fFontScale ),
	mnGlyphCount( -1 ),
	mnCachedWidth( 0 ),
	mnTrailingSpaceWidth( 0 ),
	mpGlyphIds( NULL ),
	mpCharWidths( NULL ),
	mpChars2Glyphs( NULL ),
	mpGlyphs2Chars( NULL ),
	mpGlyphRTLFlags( NULL ),
	mpGlyphAdvances( NULL ),
	mpGlyphOrigAdvs( NULL ),
	mpDeltaY( NULL ),
	mpFallbackInfo( NULL ),
	mnBaseAdv( 0 )
{}

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

ATSLayout::~ATSLayout()
{
    if( mpDeltaY )
        ATSUDirectReleaseLayoutDataArrayPtr( NULL,
            kATSUDirectDataBaselineDeltaFixedArray, (void**)&mpDeltaY );

    if( maATSULayout )
        ATSUDisposeTextLayout( maATSULayout );

    delete[] mpGlyphRTLFlags;
    delete[] mpGlyphs2Chars;
    delete[] mpChars2Glyphs;
    if( mpCharWidths != mpGlyphAdvances )
        delete[] mpCharWidths;
    delete[] mpGlyphIds;
    delete[] mpGlyphOrigAdvs;
    delete[] mpGlyphAdvances;

    delete mpFallbackInfo;
}

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

inline int ATSLayout::Fixed2Vcl( Fixed nFixed ) const
{
	float fFloat = mfFontScale * FixedToFloat( nFixed );
	return static_cast<int>(fFloat + 0.5);
}

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

inline int ATSLayout::AtsuPix2Vcl( int nAtsuPixel) const
{
	float fVclPixel = mfFontScale * nAtsuPixel;
	fVclPixel += (fVclPixel>=0) ? +0.5 : -0.5;	// prepare rounding to int
	int nVclPixel = static_cast<int>( fVclPixel);
	return nVclPixel;
}

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

inline Fixed ATSLayout::Vcl2Fixed( int nPixel ) const
{
	return FloatToFixed( nPixel / mfFontScale );
}

// -----------------------------------------------------------------------
/**
 * ATSLayout::LayoutText : Manage text layouting
 *
 * @param rArgs: contains array of char to be layouted, starting and ending position of the text to layout
 *
 * Typographic layout of text by using the style maATSUStyle
 *
 * @return : true if everything is ok
**/
bool ATSLayout::LayoutText( ImplLayoutArgs& rArgs )
{
	if( maATSULayout )
		ATSUDisposeTextLayout( maATSULayout );

    maATSULayout = NULL;

	// Layout text
	// set up our locals, verify parameters...
    DBG_ASSERT( (rArgs.mpStr!=NULL), "ATSLayout::LayoutText() with rArgs.mpStr==NULL !!!");
    DBG_ASSERT( (mrATSUStyle!=NULL), "ATSLayout::LayoutText() with ATSUStyle==NULL !!!");

	SalLayout::AdjustLayout( rArgs );
	mnCharCount = mnEndCharPos - mnMinCharPos;

	// Workaround a bug in ATSUI with empty string
	if( mnCharCount<=0 )
		return false;

#if (OSL_DEBUG_LEVEL > 3)
	Fixed fFontSize = 0;
	ByteCount nDummy;
	ATSUGetAttribute( mrATSUStyle, kATSUSizeTag, sizeof(fFontSize), &fFontSize, &nDummy);
	String aUniName( &rArgs.mpStr[rArgs.mnMinCharPos], mnCharCount );
	ByteString aCName( aUniName, RTL_TEXTENCODING_UTF8 );
	fprintf( stderr, "ATSLayout( \"%s\" %d..%d of %d) with h=%4.1f\n",
    	aCName.GetBuffer(),rArgs.mnMinCharPos,rArgs.mnEndCharPos,rArgs.mnLength,Fix2X(fFontSize) );
#endif

	// create the ATSUI layout
	UniCharCount nRunLengths[1] = { mnCharCount };
	const int nRunCount = sizeof(nRunLengths)/sizeof(*nRunLengths);
	OSStatus eStatus = ATSUCreateTextLayoutWithTextPtr( rArgs.mpStr,
        rArgs.mnMinCharPos, mnCharCount, rArgs.mnLength,
        nRunCount, &nRunLengths[0], &mrATSUStyle,
		&maATSULayout);

	DBG_ASSERT( (eStatus==noErr), "ATSUCreateTextLayoutWithTextPtr failed\n");
	if( eStatus != noErr )
		return false;

	// prepare setting of layout controls
	static const int nMaxTagCount = 1;
	ATSUAttributeTag aTagAttrs[ nMaxTagCount ];
	ByteCount aTagSizes[ nMaxTagCount ];
	ATSUAttributeValuePtr aTagValues[ nMaxTagCount ];

	// prepare control of "glyph fallback"
	const SalData* pSalData = GetSalData();
	ATSUFontFallbacks aFontFallbacks = pSalData->mpFontList->maFontFallbacks;
	aTagAttrs[0]  = kATSULineFontFallbacksTag;
	aTagSizes[0]  = sizeof( ATSUFontFallbacks );
	aTagValues[0] = &aFontFallbacks;

	// set paragraph layout controls
	ATSUSetLayoutControls( maATSULayout, 1, aTagAttrs, aTagSizes, aTagValues );

	// enable "glyph fallback"
	ATSUSetTransientFontMatching( maATSULayout, true );

	// control run-specific layout controls
	if( (rArgs.mnFlags & SAL_LAYOUT_BIDI_STRONG) != 0 )
	{
		// control BiDi defaults
		BOOL nLineDirTag = kATSULeftToRightBaseDirection;
		if( (rArgs.mnFlags & SAL_LAYOUT_BIDI_RTL) != 0 )
			nLineDirTag = kATSURightToLeftBaseDirection;
		aTagAttrs[0] = kATSULineDirectionTag;
		aTagSizes[0] = sizeof( nLineDirTag );
		aTagValues[0] = &nLineDirTag;
		// set run-specific layout controls
#if 0 // why don't line-controls work as reliably as layout-controls???
		ATSUSetLineControls( maATSULayout, rArgs.mnMinCharPos, 1, aTagAttrs, aTagSizes, aTagValues );
#else
		ATSUSetLayoutControls( maATSULayout, 1, aTagAttrs, aTagSizes, aTagValues );
#endif
	}

	return true;
}

// -----------------------------------------------------------------------
/**
 * ATSLayout::AdjustLayout : Adjust layout style
 *
 * @param rArgs: contains attributes relevant to do a text specific layout
 *
 * Adjust text layout by moving glyphs to match the requested logical widths
 *
 * @return : none
**/
void ATSLayout::AdjustLayout( ImplLayoutArgs& rArgs )
{
	int nOrigWidth = GetTextWidth();
	int nPixelWidth = rArgs.mnLayoutWidth;
	if( !nPixelWidth && rArgs.mpDXArray ) {
		// for now we are only interested in the layout width
		// TODO: use all mpDXArray elements for layouting
		nPixelWidth = rArgs.mpDXArray[ mnCharCount - 1 ];

		// workaround for ATSUI not using trailing spaces for justification
		int i = mnCharCount;
		while( (--i >= 0) && IsSpacingGlyph( rArgs.mpStr[mnMinCharPos+i]|GF_ISCHAR ) ) {}
		if( i < 0 ) // nothing to do if the text is all spaces
			return;
		// #i91685# trailing letters are left aligned (right aligned for RTL)
		mnTrailingSpaceWidth = rArgs.mpDXArray[ mnCharCount-1 ];
		if( i > 0 )
			mnTrailingSpaceWidth -= rArgs.mpDXArray[ i-1 ];
        InitGIA(); // ensure valid mpCharWidths[], TODO: use GetIdealX() instead?
		mnTrailingSpaceWidth -= Fixed2Vcl( mpCharWidths[i] );
		// ignore trailing space for calculating the available width
		nOrigWidth -= mnTrailingSpaceWidth;
		nPixelWidth -= mnTrailingSpaceWidth;
		// in RTL-layouts trailing spaces are leftmost
		// TODO: use BiDi-algorithm to thoroughly check this assumption
		if( rArgs.mnFlags & SAL_LAYOUT_BIDI_RTL)
			mnBaseAdv = mnTrailingSpaceWidth;
	}
	// return early if there is nothing to do
	if( !nPixelWidth )
		return;

	// HACK: justification requests which change the width by just one pixel were probably
	// #i86038# introduced by lossy conversions between integer based coordinate system
	// => ignoring such requests has many more benefits than eventual drawbacks
	if( (nOrigWidth >= nPixelWidth-1) && (nOrigWidth <= nPixelWidth+1) )
		return;

	// changing the layout will make all previous measurements invalid
	InvalidateMeasurements();

	ATSUAttributeTag nTags[3];
	ATSUAttributeValuePtr nVals[3];
	ByteCount nBytes[3];

	Fixed nFixedWidth = Vcl2Fixed( nPixelWidth );
	mnCachedWidth = nFixedWidth;
	Fract nFractFactor = kATSUFullJustification;
	ATSLineLayoutOptions nLineLayoutOptions = kATSLineHasNoHangers | kATSLineHasNoOpticalAlignment | kATSLineBreakToNearestCharacter;

	nTags[0] = kATSULineWidthTag;
	nVals[0] = &nFixedWidth;
	nBytes[0] = sizeof(Fixed);
	nTags[1] = kATSULineLayoutOptionsTag;
	nVals[1] = &nLineLayoutOptions;
	nBytes[1] = sizeof(ATSLineLayoutOptions);
	nTags[2] = kATSULineJustificationFactorTag;
	nVals[2] = &nFractFactor;
	nBytes[2] = sizeof(Fract);

	OSStatus eStatus = ATSUSetLayoutControls( maATSULayout, 3, nTags, nBytes, nVals );
	if( eStatus != noErr )
		return;

	// update the measurements of the justified layout to match the justification request
	if( rArgs.mpDXArray )
		InitGIA( &rArgs );
}

// -----------------------------------------------------------------------
/**
 * ATSLayout::DrawText : Draw text to screen
 *
 * @param rGraphics: device to draw to
 *
 * Draw the layouted text to the CGContext
 *
 * @return : none
**/
void ATSLayout::DrawText( SalGraphics& rGraphics ) const
{
	AquaSalGraphics& rAquaGraphics = static_cast<AquaSalGraphics&>(rGraphics);

	// short circuit if there is nothing to do
	if( (mnCharCount <= 0)
	||  !rAquaGraphics.CheckContext() )
		return;

	// the view is vertically flipped => flipped glyphs
    // so apply a temporary transformation that it flips back
	// also compensate if the font was size limited
    CGContextSaveGState( rAquaGraphics.mrContext );
    CGContextScaleCTM( rAquaGraphics.mrContext, +mfFontScale, -mfFontScale );
    CGContextSetShouldAntialias( rAquaGraphics.mrContext, !rAquaGraphics.mbNonAntialiasedText );

	// prepare ATSUI drawing attributes
	static const ItemCount nMaxControls = 8;
	ATSUAttributeTag theTags[ nMaxControls ];
	ByteCount theSizes[ nMaxControls];
	ATSUAttributeValuePtr theValues[ nMaxControls ];
	ItemCount numcontrols = 0;

	// Tell ATSUI to use CoreGraphics
    theTags[numcontrols] = kATSUCGContextTag;
    theSizes[numcontrols] = sizeof( CGContextRef );
    theValues[numcontrols++] = &rAquaGraphics.mrContext;

	// Rotate if necessary
	if( rAquaGraphics.mnATSUIRotation != 0 )
	{
		Fixed theAngle = rAquaGraphics.mnATSUIRotation;
		theTags[numcontrols] = kATSULineRotationTag;
		theSizes[numcontrols] = sizeof( Fixed );
		theValues[numcontrols++] = &theAngle;
	}

	DBG_ASSERT( (numcontrols <= nMaxControls), "ATSLayout::DrawText() numcontrols overflow" );
	OSStatus theErr = ATSUSetLayoutControls (maATSULayout, numcontrols, theTags, theSizes, theValues);
	DBG_ASSERT( (theErr==noErr), "ATSLayout::DrawText ATSUSetLayoutControls failed!\n" );

	// Draw the text
	const Point aPos = GetDrawPosition( Point(mnBaseAdv,0) );
	const Fixed nFixedX = Vcl2Fixed( +aPos.X() );
	const Fixed nFixedY = Vcl2Fixed( -aPos.Y() ); // adjusted for y-mirroring
	if( maSubPortions.empty() )
		ATSUDrawText( maATSULayout, mnMinCharPos, mnCharCount, nFixedX, nFixedY );
	else
	{
		// draw the sub-portions and apply individual adjustments
		SubPortionVector::const_iterator it = maSubPortions.begin();
		for(; it != maSubPortions.end(); ++it )
		{
			const SubPortion& rSubPortion = *it;
			// calculate sub-portion offset for rotated text
			Fixed nXOfsFixed = 0, nYOfsFixed = 0;
			if( rAquaGraphics.mnATSUIRotation != 0 )
			{
				const double fRadians = rAquaGraphics.mnATSUIRotation * (M_PI/0xB40000);
				nXOfsFixed = static_cast<Fixed>(static_cast<double>(+rSubPortion.mnXOffset) * cos( fRadians ));
				nYOfsFixed = static_cast<Fixed>(static_cast<double>(+rSubPortion.mnXOffset) * sin( fRadians ));
			}

			// draw sub-portions
			ATSUDrawText( maATSULayout,
				rSubPortion.mnMinCharPos, rSubPortion.mnEndCharPos - rSubPortion.mnMinCharPos,
				nFixedX + nXOfsFixed, nFixedY + nYOfsFixed );
		}
	}

	// request an update of the changed window area
	if( rAquaGraphics.IsWindowGraphics() )
	{
		Rect drawRect; // rectangle of the changed area
		theErr = ATSUMeasureTextImage( maATSULayout,
			mnMinCharPos, mnCharCount, nFixedX, nFixedY, &drawRect );
		if( theErr == noErr )
        {
            // FIXME: transformation from baseline to top left
            // with the simple approach below we invalidate too much
            short d = drawRect.bottom - drawRect.top;
            drawRect.top -= d;
            drawRect.bottom += d;
            CGRect aRect = CGRectMake( drawRect.left, drawRect.top,
                                       drawRect.right - drawRect.left,
                                       drawRect.bottom - drawRect.top );
            aRect = CGContextConvertRectToDeviceSpace( rAquaGraphics.mrContext, aRect );
			rAquaGraphics.RefreshRect( aRect );
        }
	}

    // restore the original graphic context transformations
	CGContextRestoreGState( rAquaGraphics.mrContext );
}

// -----------------------------------------------------------------------
/**
 * ATSLayout::GetNextGlyphs : Get info about next glyphs in the layout
 *
 * @param nLen: max number of char
 * @param pGlyphs: returned array of glyph ids
 * @param rPos: returned x starting position
 * @param nStart: index of the first requested glyph
 * @param pGlyphAdvances: returned array of glyphs advances
 * @param pCharIndexes: returned array of char indexes
 *
 * Returns infos about the next glyphs in the text layout
 *
 * @return : number of glyph details that were provided
**/
int ATSLayout::GetNextGlyphs( int nLen, sal_GlyphId* pGlyphIDs, Point& rPos, int& nStart,
    sal_Int32* pGlyphAdvances, int* pCharIndexes ) const
{
	if( nStart < 0 )                // first glyph requested?
		nStart = 0;

	// get glyph measurements
	InitGIA();
	// some measurements are only needed for multi-glyph results
	if( nLen > 1 )
	{
		GetIdealX();
		GetDeltaY();
	}

	if( nStart >= mnGlyphCount )    // no glyph left?
		return 0;

	// calculate glyph position relative to layout base
    // TODO: avoid for nStart!=0 case by reusing rPos
    Fixed nXOffset = mnBaseAdv;
    for( int i = 0; i < nStart; ++i )
        nXOffset += mpGlyphAdvances[ i ];
    // if sub-portion offsets are involved there is an additional x-offset
    if( !maSubPortions.empty() )
    {
    	// prepare to find the sub-portion
        int nCharPos = nStart + mnMinCharPos;
        if( mpGlyphs2Chars )
            nCharPos = mpGlyphs2Chars[nStart];

    	// find the matching subportion
    	// TODO: is a non-linear search worth it?
    	SubPortionVector::const_iterator it = maSubPortions.begin();
        for(; it != maSubPortions.end(); ++it) {
            const SubPortion& r = *it;
            if( nCharPos < r.mnMinCharPos )
                continue;
            if( nCharPos >= r.mnEndCharPos )
                continue;
            // apply the sub-portion xoffset
            nXOffset += r.mnXOffset;
            break;
    	}
    }

	Fixed nYOffset = 0;
	if( mpDeltaY )
		nYOffset = mpDeltaY[ nStart ];

    // calculate absolute position in pixel units
    const Point aRelativePos( Fix2Long(static_cast<Fixed>(nXOffset*mfFontScale)), Fix2Long(static_cast<Fixed>(nYOffset*mfFontScale)) );
    rPos = GetDrawPosition( aRelativePos );

	// update return values
	int nCount = 0;
    while( nCount < nLen )
    {
        ++nCount;
        sal_GlyphId nGlyphId = mpGlyphIds[nStart];

       	// check if glyph fallback is needed for this glyph
        // TODO: use ATSUDirectGetLayoutDataArrayPtrFromTextLayout(kATSUDirectDataStyleIndex) API instead?
        const int nCharPos = mpGlyphs2Chars ? mpGlyphs2Chars[nStart] : nStart + mnMinCharPos;
        ATSUFontID nFallbackFontID = kATSUInvalidFontID;
        UniCharArrayOffset nChangedOffset = 0;
        UniCharCount nChangedLength = 0;
        OSStatus eStatus = ATSUMatchFontsToText( maATSULayout, nCharPos, kATSUToTextEnd,
                      &nFallbackFontID, &nChangedOffset, &nChangedLength );
        if( (eStatus == kATSUFontsMatched) && ((int)nChangedOffset == nCharPos) )
        {
            // fallback is needed
            if( !mpFallbackInfo )
                mpFallbackInfo = new FallbackInfo;
            // register fallback font
            const int nLevel = mpFallbackInfo->AddFallback( nFallbackFontID );
       	    // update sal_GlyphId with fallback level
            nGlyphId |= (nLevel << GF_FONTSHIFT);
        }

        // update resulting glyphid array
        *(pGlyphIDs++) = nGlyphId;

        // update returned glyph advance array
        if( pGlyphAdvances )
            *(pGlyphAdvances++) = Fixed2Vcl( mpGlyphAdvances[nStart] );

        // update returned index-into-string array
        if( pCharIndexes )
        {
            int nCharPos;
            if( mpGlyphs2Chars )
                nCharPos = mpGlyphs2Chars[nStart];
            else
                nCharPos = nStart + mnMinCharPos;
            *(pCharIndexes++) = nCharPos;
        }

        // stop at last glyph
        if( ++nStart >= mnGlyphCount )
            break;

        // stop when next the x-position is unexpected
        if( !maSubPortions.empty() )
            break;	 // TODO: finish the complete sub-portion
        if( !pGlyphAdvances && mpGlyphOrigAdvs )
            if( mpGlyphAdvances[nStart-1] != mpGlyphOrigAdvs[nStart-1] )
                break;

        // stop when the next y-position is unexpected
        if( mpDeltaY )
            if( mpDeltaY[nStart-1] != mpDeltaY[nStart] )
                break;
    }

    return nCount;
}

// -----------------------------------------------------------------------
/**
 * ATSLayout::GetTextWidth : Get typographic width of layouted text
 *
 * Get typographic bounds of the text
 *
 * @return : text width
**/
long ATSLayout::GetTextWidth() const
{
	if( mnCharCount <= 0 )
		return 0;

	DBG_ASSERT( (maATSULayout!=NULL), "ATSLayout::GetTextWidth() with maATSULayout==NULL !\n");
	if( !maATSULayout )
		return 0;

	if( !mnCachedWidth )
	{
		// prepare precise measurements on pixel based or reference-device
		const UInt16 eTypeOfBounds = kATSUseFractionalOrigins;

		// determine number of needed measurement trapezoids
		ItemCount nMaxBounds = 0;
		OSStatus err = ATSUGetGlyphBounds( maATSULayout, 0, 0, mnMinCharPos, mnCharCount,
			eTypeOfBounds, 0, NULL, &nMaxBounds );
		if( (err != noErr)
		||  (nMaxBounds <= 0) )
			return 0;

		// get the trapezoids
		typedef std::vector<ATSTrapezoid> TrapezoidVector;
		TrapezoidVector aTrapezoidVector( nMaxBounds );
		ItemCount nBoundsCount = 0;
		err = ATSUGetGlyphBounds( maATSULayout, 0, 0, mnMinCharPos, mnCharCount,
			eTypeOfBounds, nMaxBounds, &aTrapezoidVector[0], &nBoundsCount );
		if( err != noErr )
			return 0;

		DBG_ASSERT( (nBoundsCount <= nMaxBounds), "ATSLayout::GetTextWidth() : too many trapezoids !\n");

		// find the bound extremas
		Fixed nLeftBound = 0;
		Fixed nRightBound = 0;
		for( ItemCount i = 0; i < nBoundsCount; ++i )
		{
			const ATSTrapezoid& rTrap = aTrapezoidVector[i];
			if( (i == 0) || (nLeftBound < rTrap.lowerLeft.x) )
				nLeftBound = rTrap.lowerLeft.x;
			if( (i == 0) || (nRightBound > rTrap.lowerRight.x) )
				nRightBound = rTrap.lowerRight.x;
		}

		// measure the bound extremas
		mnCachedWidth = nRightBound - nLeftBound;
		// adjust for eliminated trailing space widths
	}

    int nScaledWidth = Fixed2Vcl( mnCachedWidth );
	nScaledWidth += mnTrailingSpaceWidth;
    return nScaledWidth;
}

// -----------------------------------------------------------------------
/**
 * ATSLayout::FillDXArray : Get Char widths
 *
 * @param pDXArray: array to be filled with x-advances
 *
 * Fill the pDXArray with horizontal deltas : CharWidths
 *
 * @return : typographical width of the complete text layout
**/
long ATSLayout::FillDXArray( long* pDXArray ) const
{
    // short circuit requests which don't need full details
    if( !pDXArray )
        return GetTextWidth();

	// check assumptions
	DBG_ASSERT( !mnTrailingSpaceWidth, "ATSLayout::FillDXArray() with nTSW!=0" );

	// initialize details about the resulting layout
    InitGIA();

    // distribute the widths among the string elements
    int nPixWidth = 0;
    mnCachedWidth = 0;
    for( int i = 0; i < mnCharCount; ++i )
    {
        // convert and adjust for accumulated rounding errors
        mnCachedWidth += mpCharWidths[i];
        const int nOldPixWidth = nPixWidth;
        nPixWidth = Fixed2Vcl( mnCachedWidth );
        pDXArray[i] = nPixWidth - nOldPixWidth;
    }

    return nPixWidth;
}

// -----------------------------------------------------------------------
/**
 * ATSLayout::GetTextBreak : Find line break depending on width
 *
 * @param nMaxWidth : maximal logical text width in subpixel units
 * @param nCharExtra: expanded/condensed spacing in subpixel units
 * @param nFactor:    number of subpixel units per pixel
 *
 * Measure the layouted text to find the typographical line break
 * the result is needed by the language specific line breaking
 *
 * @return : string index corresponding to the suggested line break
**/
int ATSLayout::GetTextBreak( long nMaxWidth, long nCharExtra, int nFactor ) const
{
	if( !maATSULayout )
		return STRING_LEN;

	// the semantics of the legacy use case (nCharExtra!=0) cannot be mapped to ATSUBreakLine()
	if( nCharExtra != 0 )
	{
		// prepare the measurement by layouting and measuring the un-expanded/un-condensed text
		if( !InitGIA() )
			return STRING_LEN;

		// TODO: use a better way than by testing each the char position
		ATSUTextMeasurement nATSUSumWidth = 0;
		const ATSUTextMeasurement nATSUMaxWidth = Vcl2Fixed( nMaxWidth / nFactor );
		const ATSUTextMeasurement nATSUExtraWidth = Vcl2Fixed( nCharExtra ) / nFactor;
		for( int i = 0; i < mnCharCount; ++i )
		{
			nATSUSumWidth += mpCharWidths[i];
			if( nATSUSumWidth >= nATSUMaxWidth )
				return (mnMinCharPos + i);
			nATSUSumWidth += nATSUExtraWidth;
			if( nATSUSumWidth >= nATSUMaxWidth )
				if( i+1 < mnCharCount )
					return (mnMinCharPos + i);
		}

		return STRING_LEN;
	}

	// get a quick overview on what could fit
    const long nPixelWidth = (nMaxWidth - (nCharExtra * mnCharCount)) / nFactor;
    if( nPixelWidth <= 0 )
        return mnMinCharPos;

	// check assumptions
	DBG_ASSERT( !mnTrailingSpaceWidth, "ATSLayout::GetTextBreak() with nTSW!=0" );

	// initial measurement of text break position
	UniCharArrayOffset nBreakPos = mnMinCharPos;
	const ATSUTextMeasurement nATSUMaxWidth = Vcl2Fixed( nPixelWidth );
	if( nATSUMaxWidth <= 0xFFFF ) // #i108584# avoid ATSU rejecting the parameter
		return mnMinCharPos;      //           or do ATSUMaxWidth=0x10000;
	OSStatus eStatus = ATSUBreakLine( maATSULayout, mnMinCharPos,
		nATSUMaxWidth, false, &nBreakPos );
	if( (eStatus != noErr) && (eStatus != kATSULineBreakInWord) )
		return STRING_LEN;

	// the result from ATSUBreakLine() doesn't match the semantics expected by its
	// application layer callers from SW+SVX+I18N. Adjust the results to the expectations:

	// ATSU reports that everything fits even when trailing spaces would break the line
	// #i89789# OOo's application layers expect STRING_LEN if everything fits
	if( nBreakPos >= static_cast<UniCharArrayOffset>(mnEndCharPos) )
		return STRING_LEN;

	// GetTextBreak()'s callers expect it to return the "stupid visual line break".
	// Returning anything else result.s in subtle problems in the application layers.
	static const bool bInWord = true; // TODO: add as argument to GetTextBreak() method
	if( !bInWord )
		return nBreakPos;

	// emulate stupid visual line breaking by line breaking for the remaining width
	ATSUTextMeasurement nLeft, nRight, nDummy;
	eStatus = ATSUGetUnjustifiedBounds( maATSULayout, mnMinCharPos, nBreakPos-mnMinCharPos,
		&nLeft, &nRight, &nDummy, &nDummy );
	if( eStatus != noErr )
		return nBreakPos;
	const ATSUTextMeasurement nATSURemWidth = nATSUMaxWidth - (nRight - nLeft);
	if( nATSURemWidth <= 0xFFFF ) // #i108584# avoid ATSU rejecting the parameter
		return nBreakPos;
	UniCharArrayOffset nBreakPosInWord = nBreakPos;
	eStatus = ATSUBreakLine( maATSULayout, nBreakPos, nATSURemWidth, false, &nBreakPosInWord );
	return nBreakPosInWord;
}

// -----------------------------------------------------------------------
/**
 * ATSLayout::GetCaretPositions : Find positions of carets
 *
 * @param nMaxIndex position to which we want to find the carets
 *
 * Fill the array of positions of carets (for cursors and selections)
 *
 * @return : none
**/
void ATSLayout::GetCaretPositions( int nMaxIndex, long* pCaretXArray ) const
{
	DBG_ASSERT( ((nMaxIndex>0)&&!(nMaxIndex&1)),
		"ATSLayout::GetCaretPositions() : invalid number of caret pairs requested");

	// initialize the caret positions
    for( int i = 0; i < nMaxIndex; ++i )
        pCaretXArray[ i ] = -1;

	for( int n = 0; n <= mnCharCount; ++n )
	{
		// measure the characters cursor position
		typedef unsigned char Boolean;
		const Boolean bIsLeading = true;
		ATSUCaret aCaret0, aCaret1;
		Boolean bIsSplit;
		OSStatus eStatus = ATSUOffsetToCursorPosition( maATSULayout,
			mnMinCharPos + n, bIsLeading, kATSUByCharacter,
			&aCaret0, &aCaret1, &bIsSplit );
		if( eStatus != noErr )
			continue;
		const Fixed nFixedPos = mnBaseAdv + aCaret0.fX;
		// convert the measurement to pixel units
		const int nPixelPos = Fixed2Vcl( nFixedPos );
		// update previous trailing position
		if( n > 0 )
			pCaretXArray[2*n-1] = nPixelPos;
		// update current leading position
		if( 2*n >= nMaxIndex )
			break;
		pCaretXArray[2*n+0] = nPixelPos;
	}
}

// -----------------------------------------------------------------------
/**
 * ATSLayout::GetBoundRect : Get rectangle dim containing the layouted text
 *
 * @param rVCLRect: rectangle of text image (layout) measures
 *
 * Get ink bounds of the text
 *
 * @return : measurement valid
**/
bool ATSLayout::GetBoundRect( SalGraphics&, Rectangle& rVCLRect ) const
{
	const Point aPos = GetDrawPosition( Point(mnBaseAdv, 0) );
	const Fixed nFixedX = Vcl2Fixed( +aPos.X() );
	const Fixed nFixedY = Vcl2Fixed( +aPos.Y() );

	Rect aMacRect;
	OSStatus eStatus = ATSUMeasureTextImage( maATSULayout,
		mnMinCharPos, mnCharCount, nFixedX, nFixedY, &aMacRect );
	if( eStatus != noErr )
	    return false;

	// ATSU top-bottom are vertically flipped from a VCL aspect
	rVCLRect.Left()   = AtsuPix2Vcl( aMacRect.left );
	rVCLRect.Top()    = AtsuPix2Vcl( aMacRect.top );
	rVCLRect.Right()  = AtsuPix2Vcl( aMacRect.right );
	rVCLRect.Bottom() = AtsuPix2Vcl( aMacRect.bottom );
	return true;
}

// -----------------------------------------------------------------------
/**
 * ATSLayout::InitGIA() : get many informations about layouted text
 *
 * Fills arrays of information about the gylph layout previously done
 *	in ASTLayout::LayoutText() : glyph advance (width), glyph delta Y (from baseline),
 *  mapping between glyph index and character index, chars widths
 *
 * @return : true if everything could be computed, otherwise false
**/
bool ATSLayout::InitGIA( ImplLayoutArgs* pArgs ) const
{
	// no need to run InitGIA more than once on the same ATSLayout object
	if( mnGlyphCount >= 0 )
		return true;
	mnGlyphCount = 0;

	// Workaround a bug in ATSUI with empty string
	if( mnCharCount <=  0 )
		return false;

	// initialize character details
	mpCharWidths	= new Fixed[ mnCharCount ];
	mpChars2Glyphs	= new int[ mnCharCount ];
	for( int n = 0; n < mnCharCount; ++n )
	{
		mpCharWidths[ n ] = 0;
		mpChars2Glyphs[ n ] = -1;
	}

	// get details about the glyph layout
	ItemCount iLayoutDataCount;
	const ATSLayoutRecord* pALR;
	OSStatus eStatus = ATSUDirectGetLayoutDataArrayPtrFromTextLayout(
		maATSULayout, mnMinCharPos, kATSUDirectDataLayoutRecordATSLayoutRecordCurrent,
		(void**)&pALR, &iLayoutDataCount );
	DBG_ASSERT( (eStatus==noErr), "ATSLayout::InitGIA() : no ATSLayoutRecords!\n");
	if( (eStatus != noErr)
	|| (iLayoutDataCount <= 1) )
		return false;

	// initialize glyph details
	mpGlyphIds      = new ATSGlyphRef[ iLayoutDataCount ];
	mpGlyphAdvances	= new Fixed[ iLayoutDataCount ];
	mpGlyphs2Chars	= new int[ iLayoutDataCount ];

	// measure details of the glyph layout
	Fixed nLeftPos = 0;
	for( ItemCount i = 0; i < iLayoutDataCount; ++i )
	{
		const ATSLayoutRecord& rALR = pALR[i];

		// distribute the widths as fairly as possible among the chars
		const int nRelativeIdx = (rALR.originalOffset / 2);
		if( i+1 < iLayoutDataCount )
			mpCharWidths[ nRelativeIdx ] += pALR[i+1].realPos - rALR.realPos;

		// new glyph is available => finish measurement of old glyph
		if( mnGlyphCount > 0 )
			mpGlyphAdvances[ mnGlyphCount-1 ] = rALR.realPos - nLeftPos;

		// ignore marker or deleted glyphs
		enum { MARKED_OUTGLYPH=0xFFFE, DROPPED_OUTGLYPH=0xFFFF};
		if( rALR.glyphID >= MARKED_OUTGLYPH )
			continue;

		DBG_ASSERT( !(rALR.flags & kATSGlyphInfoTerminatorGlyph),
			"ATSLayout::InitGIA(): terminator glyph not marked as deleted!" );

		// store details of the visible glyphs
		nLeftPos = rALR.realPos;
		mpGlyphIds[ mnGlyphCount ] = rALR.glyphID;

		// map visible glyphs to their counterparts in the UTF16-character array
		mpGlyphs2Chars[ mnGlyphCount ] = nRelativeIdx + mnMinCharPos;
		mpChars2Glyphs[ nRelativeIdx ] = mnGlyphCount;

		++mnGlyphCount;
	}

	// measure complete width
	mnCachedWidth = mnBaseAdv;
	mnCachedWidth += pALR[iLayoutDataCount-1].realPos - pALR[0].realPos;

#if (OSL_DEBUG_LEVEL > 1)
	Fixed nWidthSum = mnBaseAdv;
	for( int n = 0; n < mnCharCount; ++n )
		nWidthSum += mpCharWidths[ n ];
	DBG_ASSERT( (nWidthSum==mnCachedWidth),
		"ATSLayout::InitGIA(): measured widths do not match!\n" );
#endif

	// #i91183# we need to split up the portion into sub-portions
	// if the ATSU-layout differs too much from the requested layout
	if( pArgs && pArgs->mpDXArray )
	{
		// TODO: non-strong-LTR case cases should be handled too
		if( (pArgs->mnFlags & TEXT_LAYOUT_BIDI_STRONG)
		&& !(pArgs->mnFlags & TEXT_LAYOUT_BIDI_RTL) )
		{
			Fixed nSumCharWidths = 0;
			SubPortion aSubPortion = { mnMinCharPos, 0, 0 };
			for( int i = 0; i < mnCharCount; ++i )
			{
				// calculate related logical position
				nSumCharWidths += mpCharWidths[i];

				// start new sub-portion if needed
				const Fixed nNextXPos = Vcl2Fixed(pArgs->mpDXArray[i]);
				const Fixed nNextXOffset = nNextXPos - nSumCharWidths;
				const Fixed nFixedDiff = aSubPortion.mnXOffset - nNextXOffset;
				if( (nFixedDiff < -0xC000) || (nFixedDiff > +0xC000) ) {
					// get to the end of the current sub-portion
					// prevent splitting up at diacritics etc.
					int j = i;
					while( (++j < mnCharCount) && !mpCharWidths[j] );
					aSubPortion.mnEndCharPos = mnMinCharPos + j;
					// emit current sub-portion
					maSubPortions.push_back( aSubPortion );
					// prepare next sub-portion
					aSubPortion.mnMinCharPos = aSubPortion.mnEndCharPos;
					aSubPortion.mnXOffset = nNextXOffset;
				}
			}

			// emit the remaining sub-portion
			if( !maSubPortions.empty() )
			{
				aSubPortion.mnEndCharPos = mnEndCharPos;
				if( aSubPortion.mnEndCharPos != aSubPortion.mnMinCharPos )
					maSubPortions.push_back( aSubPortion );
			}
		}

		// override layouted charwidths with requested charwidths
		for( int n = 0; n < mnCharCount; ++n )
			mpCharWidths[ n ] = pArgs->mpDXArray[ n ];
	}

	// release the ATSU layout records
	ATSUDirectReleaseLayoutDataArrayPtr(NULL,
		kATSUDirectDataLayoutRecordATSLayoutRecordCurrent, (void**)&pALR );

	return true;
}

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

bool ATSLayout::GetIdealX() const
{
	// compute the ideal advance widths only once
	if( mpGlyphOrigAdvs != NULL )
		return true;

	DBG_ASSERT( (mpGlyphIds!=NULL), "GetIdealX() called with mpGlyphIds==NULL !" );
	DBG_ASSERT( (mrATSUStyle!=NULL), "GetIdealX called with mrATSUStyle==NULL !" );

	// TODO: cache ideal metrics per glyph?
	std::vector<ATSGlyphIdealMetrics> aIdealMetrics;
	aIdealMetrics.resize( mnGlyphCount );
	OSStatus theErr = ATSUGlyphGetIdealMetrics( mrATSUStyle,
		mnGlyphCount, &mpGlyphIds[0], sizeof(*mpGlyphIds), &aIdealMetrics[0] );
	DBG_ASSERT( (theErr==noErr), "ATSUGlyphGetIdealMetrics failed!");
	if( theErr != noErr )
		return false;

	mpGlyphOrigAdvs = new Fixed[ mnGlyphCount ];
	for( int i = 0;i < mnGlyphCount;++i )
		mpGlyphOrigAdvs[i] = FloatToFixed( aIdealMetrics[i].advance.x );

	return true;
}

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

bool ATSLayout::GetDeltaY() const
{
	// don't bother to get the same delta-y-array more than once
	if( mpDeltaY != NULL )
		return true;

#if 1
    if( !maATSULayout )
		return false;

	// get and keep the y-deltas in the mpDeltaY member variable
	// => release it in the destructor
	ItemCount nDeltaCount = 0;
	OSStatus theErr = ATSUDirectGetLayoutDataArrayPtrFromTextLayout(
		maATSULayout, mnMinCharPos, kATSUDirectDataBaselineDeltaFixedArray,
		(void**)&mpDeltaY, &nDeltaCount );

	DBG_ASSERT( (theErr==noErr ), "mpDeltaY - ATSUDirectGetLayoutDataArrayPtrFromTextLayout failed!\n");
	if( theErr != noErr )
		return false;

	if( mpDeltaY == NULL )
		return true;

	if( nDeltaCount != (ItemCount)mnGlyphCount )
	{
		DBG_WARNING( "ATSLayout::GetDeltaY() : wrong deltaY count!" );
		ATSUDirectReleaseLayoutDataArrayPtr( NULL,
			kATSUDirectDataBaselineDeltaFixedArray,	(void**)&mpDeltaY );
		mpDeltaY = NULL;
		return false;
	}
#endif

	return true;
}

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

#define DELETEAZ( X ) { delete[] X; X = NULL; }

void ATSLayout::InvalidateMeasurements()
{
	mnGlyphCount = -1;
	DELETEAZ( mpGlyphIds );
	DELETEAZ( mpCharWidths );
	DELETEAZ( mpChars2Glyphs );
	DELETEAZ( mpGlyphs2Chars );
	DELETEAZ( mpGlyphRTLFlags );
	DELETEAZ( mpGlyphAdvances );
	DELETEAZ( mpGlyphOrigAdvs );
	DELETEAZ( mpDeltaY );
}

// =======================================================================

#if 0
// helper class to convert ATSUI outlines to VCL PolyPolygons
class PolyArgs
{
public:
				PolyArgs();
				~PolyArgs();

	void		Init( PolyPolygon* pPolyPoly, long nXOffset, long nYOffset );
	void		AddPoint( const Float32Point&, PolyFlags );
	void		ClosePolygon();

private:
	PolyPolygon* mpPolyPoly;
	long		mnXOffset, mnYOffset;

	Point*		mpPointAry;
	BYTE*		mpFlagAry;
	USHORT		mnMaxPoints;

	USHORT		mnPointCount;
	USHORT		mnPolyCount;
	bool		mbHasOffline;
};

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

PolyArgs::PolyArgs()
:	mpPolyPoly(NULL),
	mnPointCount(0),
	mnPolyCount(0),
	mbHasOffline(false)
{
	mnMaxPoints = 256;
	mpPointAry	= new Point[ mnMaxPoints ];
	mpFlagAry	= new BYTE [ mnMaxPoints ];
}

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

PolyArgs::~PolyArgs()
{
	delete[] mpFlagAry;
	delete[] mpPointAry;
}

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

void PolyArgs::Init( PolyPolygon* pPolyPoly, long nXOffset, long nYOffset )
{
	mnXOffset = nXOffset;
	mnYOffset = nYOffset;
	mpPolyPoly = pPolyPoly;

	mpPolyPoly->Clear();
	mnPointCount = 0;
	mnPolyCount  = 0;
}

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

void PolyArgs::AddPoint( const Float32Point& rPoint, PolyFlags eFlags )
{
	if( mnPointCount >= mnMaxPoints )
	{
		// resize if needed (TODO: use STL?)
		mnMaxPoints *= 4;
		Point* mpNewPoints = new Point[ mnMaxPoints ];
		BYTE* mpNewFlags = new BYTE[ mnMaxPoints ];
		for( int i = 0; i < mnPointCount; ++i )
		{
			mpNewPoints[ i ] = mpPointAry[ i ];
			mpNewFlags[ i ] = mpFlagAry[ i ];
		}
		delete[] mpFlagAry;
		delete[] mpPointAry;
		mpPointAry = mpNewPoints;
		mpFlagAry = mpNewFlags;
	}

	// convert to pixels and add startpoint offset
	int nXPos = Float32ToInt( rPoint.x );
	int nYPos = Float32ToInt( rPoint.y );
	mpPointAry[ mnPointCount ] = Point( nXPos + mnXOffset, nYPos + mnYOffset );
	// set point flags
	mpFlagAry[ mnPointCount++ ]= eFlags;
	mbHasOffline |= (eFlags != POLY_NORMAL);
}

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

void PolyArgs::ClosePolygon()
{
	if( !mnPolyCount++ )
		 return;

	// append finished polygon
	Polygon aPoly( mnPointCount, mpPointAry, (mbHasOffline ? mpFlagAry : NULL) );
	mpPolyPoly->Insert( aPoly );

	// prepare for new polygon
	mnPointCount = 0;
	mbHasOffline = false;
}
#endif
// =======================================================================

// glyph fallback is supported directly by Aqua
// so methods used only by MultiSalLayout can be dummy implementated
bool ATSLayout::GetGlyphOutlines( SalGraphics&, PolyPolyVector& ) const { return false; }
void ATSLayout::InitFont() {}
void ATSLayout::MoveGlyph( int /*nStart*/, long /*nNewXPos*/ ) {}
void ATSLayout::DropGlyph( int /*nStart*/ ) {}
void ATSLayout::Simplify( bool /*bIsBase*/ ) {}

// get the ImplFontData for a glyph fallback font
// for a glyphid that was returned by ATSLayout::GetNextGlyphs()
const ImplFontData* ATSLayout::GetFallbackFontData( sal_GlyphId nGlyphId ) const
{
    // check if any fallback fonts were needed
    if( !mpFallbackInfo )
        return NULL;
    // check if the current glyph needs a fallback font
    int nFallbackLevel = (nGlyphId & GF_FONTMASK) >> GF_FONTSHIFT;
    if( !nFallbackLevel )
        return NULL;
	return mpFallbackInfo->GetFallbackFontData( nFallbackLevel );
}

// =======================================================================

int FallbackInfo::AddFallback( ATSUFontID nFontId )
{
    // check if the fallback font is already known
    for( int nLevel = 0; nLevel < mnMaxLevel; ++nLevel )
        if( maATSUFontId[ nLevel ] == nFontId )
            return (nLevel + 1);

	// append new fallback font if possible
    if( mnMaxLevel >= MAX_FALLBACK-1 )
        return 0;
    // keep ATSU font id of fallback font
    maATSUFontId[ mnMaxLevel ] = nFontId;
    // find and cache the corresponding ImplFontData pointer
    const SystemFontList* pSFL = GetSalData()->mpFontList;
    const ImplMacFontData* pFontData = pSFL->GetFontDataFromId( nFontId );
    maFontData[ mnMaxLevel ] = pFontData;
    // increase fallback level by one
    return (++mnMaxLevel);
}

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

const ImplFontData* FallbackInfo::GetFallbackFontData( int nFallbackLevel ) const
{
    const ImplMacFontData* pFallbackFont = maFontData[ nFallbackLevel-1 ];
    return pFallbackFont;
}

// =======================================================================

SalLayout* AquaSalGraphics::GetTextLayout( ImplLayoutArgs&, int /*nFallbackLevel*/ )
{
    ATSLayout* pATSLayout = new ATSLayout( maATSUStyle, mfFontScale );
    return pATSLayout;
}

// =======================================================================