path: root/canvas/source/cairo/cairo_textlayout.cxx

/*************************************************************************
 *
 *  OpenOffice.org - a multi-platform office productivity suite
 *
 *  $RCSfile: cairo_textlayout.cxx,v $
 *
 *  $Revision: 1.5 $
 *
 *  last change: $Author: obo $ $Date: 2007-07-17 14:22:25 $
 *
 *  The Contents of this file are made available subject to
 *  the terms of GNU Lesser General Public License Version 2.1.
 *
 *
 *    GNU Lesser General Public License Version 2.1
 *    =============================================
 *    Copyright 2005 by Sun Microsystems, Inc.
 *    901 San Antonio Road, Palo Alto, CA 94303, USA
 *
 *    This library is free software; you can redistribute it and/or
 *    modify it under the terms of the GNU Lesser General Public
 *    License version 2.1, as published by the Free Software Foundation.
 *
 *    This library is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *    Lesser General Public License for more details.
 *
 *    You should have received a copy of the GNU Lesser General Public
 *    License along with this library; if not, write to the Free Software
 *    Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 *    MA  02111-1307  USA
 *
 ************************************************************************/

// MARKER(update_precomp.py): autogen include statement, do not remove
#include "precompiled_canvas.hxx"

#include <canvas/debug.hxx>
#include <canvas/verbosetrace.hxx>

#include <vcl/metric.hxx>
#include <vcl/virdev.hxx>

#include <basegfx/matrix/b2dhommatrix.hxx>
#include <basegfx/numeric/ftools.hxx>

#include <boost/scoped_array.hpp>

#include "cairo_textlayout.hxx"
#include "cairo_spritecanvas.hxx"


using namespace ::cairo;
using namespace ::com::sun::star;

namespace cairocanvas
{
    namespace
    {
        void setupLayoutMode( OutputDevice& rOutDev,
                              sal_Int8      nTextDirection )
        {
            // TODO(P3): avoid if already correctly set
            ULONG nLayoutMode;
            switch( nTextDirection )
            {
                default:
                    nLayoutMode = 0;
                    break;
                case rendering::TextDirection::WEAK_LEFT_TO_RIGHT:
                    nLayoutMode = TEXT_LAYOUT_BIDI_LTR;
                    break;
                case rendering::TextDirection::STRONG_LEFT_TO_RIGHT:
                    nLayoutMode = TEXT_LAYOUT_BIDI_LTR | TEXT_LAYOUT_BIDI_STRONG;
                    break;
                case rendering::TextDirection::WEAK_RIGHT_TO_LEFT:
                    nLayoutMode = TEXT_LAYOUT_BIDI_RTL;
                    break;
                case rendering::TextDirection::STRONG_RIGHT_TO_LEFT:
                    nLayoutMode = TEXT_LAYOUT_BIDI_RTL | TEXT_LAYOUT_BIDI_STRONG;
                    break;
            }

            // set calculated layout mode. Origin is always the left edge,
            // as required at the API spec
            rOutDev.SetLayoutMode( nLayoutMode | TEXT_LAYOUT_TEXTORIGIN_LEFT );
        }
    }

    TextLayout::TextLayout( const rendering::StringContext&     aText,
                            sal_Int8                            nDirection,
                            sal_Int64                           /*nRandomSeed*/,
                            const CanvasFont::Reference&        rFont,
                            const DeviceRef&                    rRefDevice ) :
        TextLayout_Base( m_aMutex ),
        maText( aText ),
        maLogicalAdvancements(),
        mpFont( rFont ),
        mpRefDevice( rRefDevice ),
        mnTextDirection( nDirection )
    {
    }

    TextLayout::~TextLayout()
    {
    }

    void SAL_CALL TextLayout::disposing()
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        mpFont.reset();
        mpRefDevice.clear();
    }

    // XTextLayout
    uno::Sequence< uno::Reference< rendering::XPolyPolygon2D > > SAL_CALL TextLayout::queryTextShapes(  ) throw (uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        // TODO
        return uno::Sequence< uno::Reference< rendering::XPolyPolygon2D > >();
    }

    uno::Sequence< geometry::RealRectangle2D > SAL_CALL TextLayout::queryInkMeasures(  ) throw (uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        // TODO
        return uno::Sequence< geometry::RealRectangle2D >();
    }

    uno::Sequence< geometry::RealRectangle2D > SAL_CALL TextLayout::queryMeasures(  ) throw (uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        // TODO
        return uno::Sequence< geometry::RealRectangle2D >();
    }

    uno::Sequence< double > SAL_CALL TextLayout::queryLogicalAdvancements(  ) throw (uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        return maLogicalAdvancements;
    }

    void SAL_CALL TextLayout::applyLogicalAdvancements( const uno::Sequence< double >& aAdvancements ) throw (lang::IllegalArgumentException, uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        if( aAdvancements.getLength() != maText.Length )
        {
            OSL_TRACE( "TextLayout::applyLogicalAdvancements(): mismatching number of advancements" );
            throw lang::IllegalArgumentException();
        }

        maLogicalAdvancements = aAdvancements;
    }

    geometry::RealRectangle2D SAL_CALL TextLayout::queryTextBounds(  ) throw (uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        OutputDevice* pOutDev = mpRefDevice->getOutputWindow();
        if( !pOutDev )
            return geometry::RealRectangle2D();

        VirtualDevice aVDev( *pOutDev );
        aVDev.SetFont( mpFont->getVCLFont() );

        // need metrics for Y offset, the XCanvas always renders
        // relative to baseline
        const ::FontMetric& aMetric( aVDev.GetFontMetric() );

        setupLayoutMode( aVDev, mnTextDirection );

        const sal_Int32 nAboveBaseline( -aMetric.GetIntLeading() - aMetric.GetAscent() );
        const sal_Int32 nBelowBaseline( aMetric.GetDescent() );

        if( maLogicalAdvancements.getLength() )
        {
            return geometry::RealRectangle2D( 0, nAboveBaseline,
                                              maLogicalAdvancements[ maLogicalAdvancements.getLength()-1 ],
                                              nBelowBaseline );
        }
        else
        {
            return geometry::RealRectangle2D( 0, nAboveBaseline,
                                              aVDev.GetTextWidth(
                                                  maText.Text,
                                                  ::canvas::tools::numeric_cast<USHORT>(maText.StartPosition),
                                                  ::canvas::tools::numeric_cast<USHORT>(maText.Length) ),
                                              nBelowBaseline );
        }
    }

    double SAL_CALL TextLayout::justify( double /*nSize*/ ) throw (lang::IllegalArgumentException, uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        // TODO
        return 0.0;
    }

    double SAL_CALL TextLayout::combinedJustify( const uno::Sequence< uno::Reference< rendering::XTextLayout > >& /*aNextLayouts*/,
                                                 double /*nSize*/ ) throw (lang::IllegalArgumentException, uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        // TODO
        return 0.0;
    }

    rendering::TextHit SAL_CALL TextLayout::getTextHit( const geometry::RealPoint2D& /*aHitPoint*/ ) throw (uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        // TODO
        return rendering::TextHit();
    }

    rendering::Caret SAL_CALL TextLayout::getCaret( sal_Int32 /*nInsertionIndex*/,
                                                    sal_Bool /*bExcludeLigatures*/ ) throw (lang::IndexOutOfBoundsException, uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        // TODO
        return rendering::Caret();
    }

    sal_Int32 SAL_CALL TextLayout::getNextInsertionIndex( sal_Int32 /*nStartIndex*/,
                                                          sal_Int32 /*nCaretAdvancement*/,
                                                          sal_Bool /*bExcludeLigatures*/ ) throw (lang::IndexOutOfBoundsException, uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        // TODO
        return 0;
    }

    uno::Reference< rendering::XPolyPolygon2D > SAL_CALL TextLayout::queryVisualHighlighting( sal_Int32 /*nStartIndex*/,
                                                                                              sal_Int32 /*nEndIndex*/ ) throw (lang::IndexOutOfBoundsException, uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        // TODO
        return uno::Reference< rendering::XPolyPolygon2D >();
    }

    uno::Reference< rendering::XPolyPolygon2D > SAL_CALL TextLayout::queryLogicalHighlighting( sal_Int32 /*nStartIndex*/,
                                                                                               sal_Int32 /*nEndIndex*/ ) throw (lang::IndexOutOfBoundsException, uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        // TODO
        return uno::Reference< rendering::XPolyPolygon2D >();
    }

    double SAL_CALL TextLayout::getBaselineOffset(  ) throw (uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        // TODO
        return 0.0;
    }

    sal_Int8 SAL_CALL TextLayout::getMainTextDirection(  ) throw (uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        return mnTextDirection;
    }

    uno::Reference< rendering::XCanvasFont > SAL_CALL TextLayout::getFont(  ) throw (uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        return mpFont.getRef();
    }

    rendering::StringContext SAL_CALL TextLayout::getText(  ) throw (uno::RuntimeException)
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        return maText;
    }

    void TextLayout::useFont( Cairo* pCairo )
    {
    rendering::FontRequest aFontRequest = mpFont->getFontRequest();
    rendering::FontInfo aFontInfo = aFontRequest.FontDescription;

    cairo_select_font_face( pCairo, ::rtl::OUStringToOString( aFontInfo.FamilyName, RTL_TEXTENCODING_UTF8 ), CAIRO_FONT_SLANT_NORMAL, CAIRO_FONT_WEIGHT_NORMAL );
    cairo_set_font_size( pCairo, aFontRequest.CellSize );
    }

    bool TextLayout::draw( Cairo* pCairo )
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        ::rtl::OUString aSubText = maText.Text.copy( maText.StartPosition, maText.Length );
        ::rtl::OString aUTF8String = ::rtl::OUStringToOString( aSubText, RTL_TEXTENCODING_UTF8 );

        cairo_save( pCairo );
        /* move to 0, 0 as cairo_show_text advances current point and current point is not restored by cairo_restore.
           before we were depending on unmodified current point which I believed was preserved by save/restore */
        cairo_move_to( pCairo, 0, 0 );
        useFont( pCairo );
        cairo_show_text( pCairo, aUTF8String );
        cairo_restore( pCairo );

        return true;
    }

    namespace
    {
        class OffsetTransformer
        {
        public:
            OffsetTransformer( const ::basegfx::B2DHomMatrix& rMat ) :
                maMatrix( rMat )
            {
            }

            sal_Int32 operator()( const double& rOffset )
            {
                // This is an optimization of the normal rMat*[x,0]
                // transformation of the advancement vector (in x
                // direction), followed by a length calculation of the
                // resulting vector: advancement' =
                // ||rMat*[x,0]||. Since advancements are vectors, we
                // can ignore translational components, thus if [x,0],
                // it follows that rMat*[x,0]=[x',0] holds. Thus, we
                // just have to calc the transformation of the x
                // component.

                // TODO(F2): Handle non-horizontal advancements!
                return ::basegfx::fround( hypot(maMatrix.get(0,0)*rOffset,
                                                maMatrix.get(1,0)*rOffset) );
            }

        private:
            ::basegfx::B2DHomMatrix maMatrix;
        };
    }

    void TextLayout::setupTextOffsets( sal_Int32*                       outputOffsets,
                                       const uno::Sequence< double >&   inputOffsets,
                                       const rendering::ViewState&      viewState,
                                       const rendering::RenderState&    renderState     ) const
    {
        ENSURE_AND_THROW( outputOffsets!=NULL,
                          "TextLayout::setupTextOffsets offsets NULL" );

        ::basegfx::B2DHomMatrix aMatrix;

        ::canvas::tools::mergeViewAndRenderTransform(aMatrix,
                                                     viewState,
                                                     renderState);

        // fill integer offsets
        ::std::transform( const_cast< uno::Sequence< double >& >(inputOffsets).getConstArray(),
                          const_cast< uno::Sequence< double >& >(inputOffsets).getConstArray()+inputOffsets.getLength(),
                          outputOffsets,
                          OffsetTransformer( aMatrix ) );
    }

    bool TextLayout::draw( OutputDevice&                 rOutDev,
                           const Point&                  rOutpos,
                           const rendering::ViewState&   viewState,
                           const rendering::RenderState& renderState ) const
    {
        ::osl::MutexGuard aGuard( m_aMutex );

        setupLayoutMode( rOutDev, mnTextDirection );

        if( maLogicalAdvancements.getLength() )
        {
            // TODO(P2): cache that
            ::boost::scoped_array< sal_Int32 > aOffsets(new sal_Int32[maLogicalAdvancements.getLength()]);
            setupTextOffsets( aOffsets.get(), maLogicalAdvancements, viewState, renderState );

            // TODO(F3): ensure correct length and termination for DX
            // array (last entry _must_ contain the overall width)

            rOutDev.DrawTextArray( rOutpos,
                                   maText.Text,
                                   aOffsets.get(),
                                   ::canvas::tools::numeric_cast<USHORT>(maText.StartPosition),
                                   ::canvas::tools::numeric_cast<USHORT>(maText.Length) );
        }
        else
        {
            rOutDev.DrawText( rOutpos,
                              maText.Text,
                              ::canvas::tools::numeric_cast<USHORT>(maText.StartPosition),
                              ::canvas::tools::numeric_cast<USHORT>(maText.Length) );
        }

        return true;
    }

#define SERVICE_NAME "com.sun.star.rendering.TextLayout"
#define IMPLEMENTATION_NAME "CairoCanvas::TextLayout"

    ::rtl::OUString SAL_CALL TextLayout::getImplementationName() throw( uno::RuntimeException )
    {
        return ::rtl::OUString( RTL_CONSTASCII_USTRINGPARAM( IMPLEMENTATION_NAME ) );
    }

    sal_Bool SAL_CALL TextLayout::supportsService( const ::rtl::OUString& ServiceName ) throw( uno::RuntimeException )
    {
        return ServiceName.equalsAsciiL( RTL_CONSTASCII_STRINGPARAM ( SERVICE_NAME ) );
    }

    uno::Sequence< ::rtl::OUString > SAL_CALL TextLayout::getSupportedServiceNames()  throw( uno::RuntimeException )
    {
        uno::Sequence< ::rtl::OUString > aRet(1);
        aRet[0] = ::rtl::OUString( RTL_CONSTASCII_USTRINGPARAM ( SERVICE_NAME ) );

        return aRet;
    }
}