canvas/source/cairo/cairo_textlayout.cxx

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  27
  28 // MARKER(update_precomp.py): autogen include statement, do not remove
  29 #include "precompiled_canvas.hxx"
  30
  31 #include <math.h>
  32
  33 #include <canvas/debug.hxx>
  34 #include <canvas/verbosetrace.hxx>
  35 #include <tools/diagnose_ex.h>
  36
  37 #include <vcl/metric.hxx>
  38 #include <vcl/virdev.hxx>
  39
  40 #ifdef WNT
  41 #include <tools/prewin.h>
  42 #include <windows.h>
  43 #include <tools/postwin.h>
  44 #ifdef max
  45 #undef max
  46 #endif
  47 #ifdef min
  48 #undef min
  49 #endif
  50 #endif
  51 #include <vcl/sysdata.hxx>
  52
  53 #include <basegfx/matrix/b2dhommatrix.hxx>
  54 #include <basegfx/numeric/ftools.hxx>
  55
  56 #include <boost/scoped_array.hpp>
  57
  58 #include "cairo_textlayout.hxx"
  59 #include "cairo_spritecanvas.hxx"
  60
  61 #ifdef CAIRO_HAS_QUARTZ_SURFACE
  62 # include "cairo_quartz_cairo.hxx"
  63 #elif defined CAIRO_HAS_WIN32_SURFACE
  64 # include "cairo_win32_cairo.hxx"
  65 # include <cairo-win32.h>
  66 #elif defined CAIRO_HAS_XLIB_SURFACE
  67 # include "cairo_xlib_cairo.hxx"
  68 # include <cairo-ft.h>
  69 #else
  70 # error Native API needed.
  71 #endif
  72
  73 using namespace ::cairo;
  74 using namespace ::com::sun::star;
  75
  76 namespace cairocanvas
  77 {
  78     namespace
  79     {
  80         void setupLayoutMode( OutputDevice& rOutDev,
  81                               sal_Int8      nTextDirection )
  82         {
  83             // TODO(P3): avoid if already correctly set
  84             sal_uLong nLayoutMode;
  85             switch( nTextDirection )
  86             {
  87                 default:
  88                     nLayoutMode = 0;
  89                     break;
  90                 case rendering::TextDirection::WEAK_LEFT_TO_RIGHT:
  91                     nLayoutMode = TEXT_LAYOUT_BIDI_LTR;
  92                     break;
  93                 case rendering::TextDirection::STRONG_LEFT_TO_RIGHT:
  94                     nLayoutMode = TEXT_LAYOUT_BIDI_LTR | TEXT_LAYOUT_BIDI_STRONG;
  95                     break;
  96                 case rendering::TextDirection::WEAK_RIGHT_TO_LEFT:
  97                     nLayoutMode = TEXT_LAYOUT_BIDI_RTL;
  98                     break;
  99                 case rendering::TextDirection::STRONG_RIGHT_TO_LEFT:
 100                     nLayoutMode = TEXT_LAYOUT_BIDI_RTL | TEXT_LAYOUT_BIDI_STRONG;
 101                     break;
 102             }
 103
 104             // set calculated layout mode. Origin is always the left edge,
 105             // as required at the API spec
 106             rOutDev.SetLayoutMode( nLayoutMode | TEXT_LAYOUT_TEXTORIGIN_LEFT );
 107         }
 108
 109         bool compareFallbacks(const SystemGlyphData&rA, const SystemGlyphData &rB)
 110         {
 111             return rA.fallbacklevel < rB.fallbacklevel;
 112         }
 113     }
 114
 115     TextLayout::TextLayout( const rendering::StringContext&     aText,
 116                             sal_Int8                            nDirection,
 117                             sal_Int64                           /*nRandomSeed*/,
 118                             const CanvasFont::Reference&        rFont,
 119                             const SurfaceProviderRef&           rRefDevice ) :
 120         TextLayout_Base( m_aMutex ),
 121         maText( aText ),
 122         maLogicalAdvancements(),
 123         mpFont( rFont ),
 124         mpRefDevice( rRefDevice ),
 125         mnTextDirection( nDirection )
 126     {
 127     }
 128
 129     TextLayout::~TextLayout()
 130     {
 131     }
 132
 133     void SAL_CALL TextLayout::disposing()
 134     {
 135         ::osl::MutexGuard aGuard( m_aMutex );
 136
 137         mpFont.reset();
 138         mpRefDevice.clear();
 139     }
 140
 141     // XTextLayout
 142     uno::Sequence< uno::Reference< rendering::XPolyPolygon2D > > SAL_CALL TextLayout::queryTextShapes(  ) throw (uno::RuntimeException)
 143     {
 144         ::osl::MutexGuard aGuard( m_aMutex );
 145
 146         // TODO
 147         return uno::Sequence< uno::Reference< rendering::XPolyPolygon2D > >();
 148     }
 149
 150     uno::Sequence< geometry::RealRectangle2D > SAL_CALL TextLayout::queryInkMeasures(  ) throw (uno::RuntimeException)
 151     {
 152         ::osl::MutexGuard aGuard( m_aMutex );
 153
 154         // TODO
 155         return uno::Sequence< geometry::RealRectangle2D >();
 156     }
 157
 158     uno::Sequence< geometry::RealRectangle2D > SAL_CALL TextLayout::queryMeasures(  ) throw (uno::RuntimeException)
 159     {
 160         ::osl::MutexGuard aGuard( m_aMutex );
 161
 162         // TODO
 163         return uno::Sequence< geometry::RealRectangle2D >();
 164     }
 165
 166     uno::Sequence< double > SAL_CALL TextLayout::queryLogicalAdvancements(  ) throw (uno::RuntimeException)
 167     {
 168         ::osl::MutexGuard aGuard( m_aMutex );
 169
 170         return maLogicalAdvancements;
 171     }
 172
 173     void SAL_CALL TextLayout::applyLogicalAdvancements( const uno::Sequence< double >& aAdvancements ) throw (lang::IllegalArgumentException, uno::RuntimeException)
 174     {
 175         ::osl::MutexGuard aGuard( m_aMutex );
 176
 177         if( aAdvancements.getLength() != maText.Length )
 178         {
 179             OSL_TRACE( "TextLayout::applyLogicalAdvancements(): mismatching number of advancements" );
 180             throw lang::IllegalArgumentException();
 181         }
 182
 183         maLogicalAdvancements = aAdvancements;
 184     }
 185
 186     geometry::RealRectangle2D SAL_CALL TextLayout::queryTextBounds(  ) throw (uno::RuntimeException)
 187     {
 188         ::osl::MutexGuard aGuard( m_aMutex );
 189
 190         OutputDevice* pOutDev = mpRefDevice->getOutputDevice();
 191         if( !pOutDev )
 192             return geometry::RealRectangle2D();
 193
 194         VirtualDevice aVDev( *pOutDev );
 195         aVDev.SetFont( mpFont->getVCLFont() );
 196
 197         // need metrics for Y offset, the XCanvas always renders
 198         // relative to baseline
 199         const ::FontMetric& aMetric( aVDev.GetFontMetric() );
 200
 201         setupLayoutMode( aVDev, mnTextDirection );
 202
 203         const sal_Int32 nAboveBaseline( -aMetric.GetIntLeading() - aMetric.GetAscent() );
 204         const sal_Int32 nBelowBaseline( aMetric.GetDescent() );
 205
 206         if( maLogicalAdvancements.getLength() )
 207         {
 208             return geometry::RealRectangle2D( 0, nAboveBaseline,
 209                                               maLogicalAdvancements[ maLogicalAdvancements.getLength()-1 ],
 210                                               nBelowBaseline );
 211         }
 212         else
 213         {
 214             return geometry::RealRectangle2D( 0, nAboveBaseline,
 215                                               aVDev.GetTextWidth(
 216                                                   maText.Text,
 217                                                   ::canvas::tools::numeric_cast<USHORT>(maText.StartPosition),
 218                                                   ::canvas::tools::numeric_cast<USHORT>(maText.Length) ),
 219                                               nBelowBaseline );
 220         }
 221     }
 222
 223     double SAL_CALL TextLayout::justify( double /*nSize*/ ) throw (lang::IllegalArgumentException, uno::RuntimeException)
 224     {
 225         ::osl::MutexGuard aGuard( m_aMutex );
 226
 227         // TODO
 228         return 0.0;
 229     }
 230
 231     double SAL_CALL TextLayout::combinedJustify( const uno::Sequence< uno::Reference< rendering::XTextLayout > >& /*aNextLayouts*/,
 232                                                  double /*nSize*/ ) throw (lang::IllegalArgumentException, uno::RuntimeException)
 233     {
 234         ::osl::MutexGuard aGuard( m_aMutex );
 235
 236         // TODO
 237         return 0.0;
 238     }
 239
 240     rendering::TextHit SAL_CALL TextLayout::getTextHit( const geometry::RealPoint2D& /*aHitPoint*/ ) throw (uno::RuntimeException)
 241     {
 242         ::osl::MutexGuard aGuard( m_aMutex );
 243
 244         // TODO
 245         return rendering::TextHit();
 246     }
 247
 248     rendering::Caret SAL_CALL TextLayout::getCaret( sal_Int32 /*nInsertionIndex*/,
 249                                                     sal_Bool /*bExcludeLigatures*/ ) throw (lang::IndexOutOfBoundsException, uno::RuntimeException)
 250     {
 251         ::osl::MutexGuard aGuard( m_aMutex );
 252
 253         // TODO
 254         return rendering::Caret();
 255     }
 256
 257     sal_Int32 SAL_CALL TextLayout::getNextInsertionIndex( sal_Int32 /*nStartIndex*/,
 258                                                           sal_Int32 /*nCaretAdvancement*/,
 259                                                           sal_Bool /*bExcludeLigatures*/ ) throw (lang::IndexOutOfBoundsException, uno::RuntimeException)
 260     {
 261         ::osl::MutexGuard aGuard( m_aMutex );
 262
 263         // TODO
 264         return 0;
 265     }
 266
 267     uno::Reference< rendering::XPolyPolygon2D > SAL_CALL TextLayout::queryVisualHighlighting( sal_Int32 /*nStartIndex*/,
 268                                                                                               sal_Int32 /*nEndIndex*/ ) throw (lang::IndexOutOfBoundsException, uno::RuntimeException)
 269     {
 270         ::osl::MutexGuard aGuard( m_aMutex );
 271
 272         // TODO
 273         return uno::Reference< rendering::XPolyPolygon2D >();
 274     }
 275
 276     uno::Reference< rendering::XPolyPolygon2D > SAL_CALL TextLayout::queryLogicalHighlighting( sal_Int32 /*nStartIndex*/,
 277                                                                                                sal_Int32 /*nEndIndex*/ ) throw (lang::IndexOutOfBoundsException, uno::RuntimeException)
 278     {
 279         ::osl::MutexGuard aGuard( m_aMutex );
 280
 281         // TODO
 282         return uno::Reference< rendering::XPolyPolygon2D >();
 283     }
 284
 285     double SAL_CALL TextLayout::getBaselineOffset(  ) throw (uno::RuntimeException)
 286     {
 287         ::osl::MutexGuard aGuard( m_aMutex );
 288
 289         // TODO
 290         return 0.0;
 291     }
 292
 293     sal_Int8 SAL_CALL TextLayout::getMainTextDirection(  ) throw (uno::RuntimeException)
 294     {
 295         ::osl::MutexGuard aGuard( m_aMutex );
 296
 297         return mnTextDirection;
 298     }
 299
 300     uno::Reference< rendering::XCanvasFont > SAL_CALL TextLayout::getFont(  ) throw (uno::RuntimeException)
 301     {
 302         ::osl::MutexGuard aGuard( m_aMutex );
 303
 304         return mpFont.getRef();
 305     }
 306
 307     rendering::StringContext SAL_CALL TextLayout::getText(  ) throw (uno::RuntimeException)
 308     {
 309         ::osl::MutexGuard aGuard( m_aMutex );
 310
 311         return maText;
 312     }
 313
 314     void TextLayout::useFont( Cairo* pCairo )
 315     {
 316     rendering::FontRequest aFontRequest = mpFont->getFontRequest();
 317     rendering::FontInfo aFontInfo = aFontRequest.FontDescription;
 318
 319     cairo_select_font_face( pCairo, ::rtl::OUStringToOString( aFontInfo.FamilyName, RTL_TEXTENCODING_UTF8 ), CAIRO_FONT_SLANT_NORMAL, CAIRO_FONT_WEIGHT_NORMAL );
 320     cairo_set_font_size( pCairo, aFontRequest.CellSize );
 321     }
 322
 323   /** TextLayout:draw
 324    *
 325    * This function uses the "toy" api of the cairo library
 326    *
 327    **/
 328     bool TextLayout::draw( Cairo* pCairo )
 329     {
 330         ::osl::MutexGuard aGuard( m_aMutex );
 331
 332         ::rtl::OUString aSubText = maText.Text.copy( maText.StartPosition, maText.Length );
 333         ::rtl::OString aUTF8String = ::rtl::OUStringToOString( aSubText, RTL_TEXTENCODING_UTF8 );
 334
 335         cairo_save( pCairo );
 336         /* move to 0, 0 as cairo_show_text advances current point and current point is not restored by cairo_restore.
 337            before we were depending on unmodified current point which I believed was preserved by save/restore */
 338         cairo_move_to( pCairo, 0, 0 );
 339         useFont( pCairo );
 340         cairo_show_text( pCairo, aUTF8String );
 341         cairo_restore( pCairo );
 342
 343         return true;
 344     }
 345
 346
 347   /**
 348    * TextLayout::isCairoRenderable
 349    *
 350    * Features currenly not supported by Cairo (VCL rendering is used as fallback):
 351    * - vertical glyphs
 352    *
 353    * @return true, if text/font can be rendered with cairo
 354    **/
 355     bool TextLayout::isCairoRenderable(SystemFontData aSysFontData) const
 356     {
 357 #if defined UNX && !defined QUARTZ
 358         // is font usable?
 359         if (!aSysFontData.nFontId) return false;
 360 #endif
 361
 362         // vertical glyph rendering is not supported in cairo for now
 363         if (aSysFontData.bVerticalCharacterType) {
 364             OSL_TRACE(":cairocanvas::TextLayout::isCairoRenderable(): ***************** VERTICAL CHARACTER STYLE!!! ****************");
 365             return false;
 366         }
 367
 368         return true;
 369     }
 370
 371   /**
 372    * TextLayout::draw
 373    *
 374    * Cairo-based text rendering. Draw text directly on the cairo surface with cairo fonts.
 375    * Avoid using VCL VirtualDevices for that, bypassing VCL DrawText functions, when possible
 376    *
 377    * Note: some text effects are not rendered due to lacking generic canvas or cairo canvas
 378    *       implementation. See issues 92657, 92658, 92659, 92660, 97529
 379    *
 380    * @return true, if successful
 381    **/
 382     bool TextLayout::draw( SurfaceSharedPtr&             pSurface,
 383                            OutputDevice&                 rOutDev,
 384                            const Point&                  rOutpos,
 385                            const rendering::ViewState&   viewState,
 386                            const rendering::RenderState& renderState ) const
 387     {
 388         ::osl::MutexGuard aGuard( m_aMutex );
 389         SystemTextLayoutData aSysLayoutData;
 390 #if (defined CAIRO_HAS_WIN32_SURFACE) && (OSL_DEBUG_LEVEL > 1)
 391         LOGFONTW logfont;
 392 #endif
 393         setupLayoutMode( rOutDev, mnTextDirection );
 394
 395         // TODO(P2): cache that
 396         ::boost::scoped_array< sal_Int32 > aOffsets(new sal_Int32[maLogicalAdvancements.getLength()]);
 397
 398         if( maLogicalAdvancements.getLength() )
 399         {
 400             setupTextOffsets( aOffsets.get(), maLogicalAdvancements, viewState, renderState );
 401
 402             // TODO(F3): ensure correct length and termination for DX
 403             // array (last entry _must_ contain the overall width)
 404         }
 405
 406         aSysLayoutData = rOutDev.GetSysTextLayoutData(rOutpos, maText.Text,
 407                                                       ::canvas::tools::numeric_cast<USHORT>(maText.StartPosition),
 408                                                       ::canvas::tools::numeric_cast<USHORT>(maText.Length),
 409                                                       maLogicalAdvancements.getLength() ? aOffsets.get() : NULL);
 410
 411         // Sort them so that all glyphs on the same glyph fallback level are consecutive
 412         std::sort(aSysLayoutData.rGlyphData.begin(), aSysLayoutData.rGlyphData.end(), compareFallbacks);
 413         bool bCairoRenderable = true;
 414
 415         //Pull all the fonts we need to render the text
 416         typedef std::pair<SystemFontData,int> FontLevel;
 417         typedef std::vector<FontLevel> FontLevelVector;
 418         FontLevelVector aFontData;
 419         SystemGlyphDataVector::const_iterator aIter=aSysLayoutData.rGlyphData.begin();
 420         const SystemGlyphDataVector::const_iterator aEnd=aSysLayoutData.rGlyphData.end();
 421         for( ; aIter != aEnd; ++aIter )
 422         {
 423             if( aFontData.empty() || aIter->fallbacklevel != aFontData.back().second )
 424             {
 425                 aFontData.push_back(FontLevel(rOutDev.GetSysFontData(aIter->fallbacklevel),
 426                                               aIter->fallbacklevel));
 427                 if( !isCairoRenderable(aFontData.back().first) )
 428                 {
 429                     bCairoRenderable = false;
 430                     OSL_TRACE(":cairocanvas::TextLayout::draw(S,O,p,v,r): VCL FALLBACK %s%s%s%s - %s",
 431                               maLogicalAdvancements.getLength() ? "ADV " : "",
 432                               aFontData.back().first.bAntialias ? "AA " : "",
 433                               aFontData.back().first.bFakeBold ? "FB " : "",
 434                               aFontData.back().first.bFakeItalic ? "FI " : "",
 435                               ::rtl::OUStringToOString( maText.Text.copy( maText.StartPosition, maText.Length ),
 436                                                         RTL_TEXTENCODING_UTF8 ).getStr());
 437                     break;
 438                 }
 439             }
 440         }
 441
 442         // The ::GetSysTextLayoutData(), i.e. layouting of text to glyphs can change the font being used.
 443         // The fallback checks need to be done after final font is known.
 444         if (!bCairoRenderable)    // VCL FALLBACKS
 445         {
 446             if (maLogicalAdvancements.getLength())        // VCL FALLBACK - with glyph advances
 447             {
 448                 rOutDev.DrawTextArray( rOutpos, maText.Text, aOffsets.get(),
 449                                        ::canvas::tools::numeric_cast<USHORT>(maText.StartPosition),
 450                                        ::canvas::tools::numeric_cast<USHORT>(maText.Length) );
 451                 return true;
 452             }
 453             else                                               // VCL FALLBACK - without advances
 454             {
 455                 rOutDev.DrawText( rOutpos, maText.Text,
 456                                   ::canvas::tools::numeric_cast<USHORT>(maText.StartPosition),
 457                                   ::canvas::tools::numeric_cast<USHORT>(maText.Length) );
 458                 return true;
 459             }
 460         }
 461
 462         if (aSysLayoutData.rGlyphData.empty()) return false; //??? false?
 463
 464         /**
 465          * Setup platform independent glyph vector into cairo-based glyphs vector.
 466          **/
 467
 468         // Loop through the fonts used and render the matching glyphs for each
 469         FontLevelVector::const_iterator aFontDataIter = aFontData.begin();
 470         const FontLevelVector::const_iterator aFontDataEnd = aFontData.end();
 471         for( ; aFontDataIter != aFontDataEnd; ++aFontDataIter )
 472         {
 473             const SystemFontData &rSysFontData = aFontDataIter->first;
 474
 475             // setup glyphs
 476             std::vector<cairo_glyph_t> cairo_glyphs;
 477             cairo_glyphs.reserve( 256 );
 478
 479             SystemGlyphDataVector::const_iterator aIter=aSysLayoutData.rGlyphData.begin();
 480             const SystemGlyphDataVector::const_iterator aEnd=aSysLayoutData.rGlyphData.end();
 481             for( ; aIter != aEnd; ++aIter )
 482             {
 483                 SystemGlyphData systemGlyph = *aIter;
 484                 if( systemGlyph.fallbacklevel != aFontDataIter->second )
 485                     continue;
 486
 487                 cairo_glyph_t aGlyph;
 488                 aGlyph.index = systemGlyph.index;
 489     #ifdef CAIRO_HAS_WIN32_SURFACE
 490                 // Cairo requires standard glyph indexes (ETO_GLYPH_INDEX), while vcl/win/* uses ucs4 chars.
 491                 // Convert to standard indexes
 492                 aGlyph.index = cairo::ucs4toindex((unsigned int) aGlyph.index, rSysFontData.hFont);
 493     #endif
 494                 aGlyph.x = systemGlyph.x;
 495                 aGlyph.y = systemGlyph.y;
 496                 cairo_glyphs.push_back(aGlyph);
 497             }
 498
 499             if (cairo_glyphs.empty())
 500                 continue;
 501
 502             /**
 503              * Setup font
 504              **/
 505             cairo_font_face_t* font_face = NULL;
 506
 507     #ifdef CAIRO_HAS_QUARTZ_SURFACE
 508             // TODO: use cairo_quartz_font_face_create_for_cgfont(cgFont)
 509             //       when CGFont (Mac OS X 10.5 API) is provided by the AQUA VCL backend.
 510             font_face = cairo_quartz_font_face_create_for_atsu_font_id((ATSUFontID) rSysFontData.aATSUFontID);
 511
 512     #elif defined CAIRO_HAS_WIN32_SURFACE
 513       #if (OSL_DEBUG_LEVEL > 1)
 514             GetObjectW( rSysFontData.hFont, sizeof(logfont), &logfont );
 515       #endif
 516             // Note: cairo library uses logfont fallbacks when lfEscapement, lfOrientation and lfWidth are not zero.
 517             // VCL always has non-zero value for lfWidth
 518             font_face = cairo_win32_font_face_create_for_hfont(rSysFontData.hFont);
 519
 520     #elif defined CAIRO_HAS_XLIB_SURFACE
 521             font_face = cairo_ft_font_face_create_for_ft_face((FT_Face)rSysFontData.nFontId,
 522                                                               rSysFontData.nFontFlags);
 523     #else
 524     # error Native API needed.
 525     #endif
 526
 527             CairoSharedPtr pSCairo = pSurface->getCairo();
 528
 529             cairo_set_font_face( pSCairo.get(), font_face);
 530
 531             // create default font options. cairo_get_font_options() does not retrieve the surface defaults,
 532             // only what has been set before with cairo_set_font_options()
 533             cairo_font_options_t* options = cairo_font_options_create();
 534             if (rSysFontData.bAntialias) {
 535                 // CAIRO_ANTIALIAS_GRAY provides more similar result to VCL Canvas,
 536                 // so we're not using CAIRO_ANTIALIAS_SUBPIXEL
 537                 cairo_font_options_set_antialias(options, CAIRO_ANTIALIAS_GRAY);
 538             }
 539             cairo_set_font_options( pSCairo.get(), options);
 540
 541             // Font color
 542             Color mTextColor = rOutDev.GetTextColor();
 543             cairo_set_source_rgb(pSCairo.get(),
 544                                  mTextColor.GetRed()/255.0,
 545                                  mTextColor.GetGreen()/255.0,
 546                                  mTextColor.GetBlue()/255.0);
 547
 548             // Font rotation and scaling
 549             cairo_matrix_t m;
 550             Font aFont = rOutDev.GetFont();
 551             FontMetric aMetric( rOutDev.GetFontMetric(aFont) );
 552             long nWidth = 0;
 553
 554             // width calculation is deep magic and platform/font dependant.
 555             // width == 0 means no scaling, and usually width == height means the same.
 556             // Other values mean horizontal scaling (narrow or stretching)
 557             // see issue #101566
 558
 559             //proper scale calculation across platforms
 560             if (aFont.GetWidth() == 0) {
 561                 nWidth = aFont.GetHeight();
 562             } else {
 563                 // any scaling needs to be relative to the platform-dependent definition
 564                 // of height of the font
 565                 nWidth = aFont.GetWidth() * aFont.GetHeight() / aMetric.GetHeight();
 566             }
 567
 568             cairo_matrix_init_identity(&m);
 569
 570             if (aSysLayoutData.orientation) cairo_matrix_rotate(&m, (3600 - aSysLayoutData.orientation) * M_PI / 1800.0);
 571
 572             cairo_matrix_scale(&m, nWidth, aFont.GetHeight());
 573
 574             //faux italics
 575             if (rSysFontData.bFakeItalic) m.xy = -m.xx * 0x6000L / 0x10000L;
 576
 577             cairo_set_font_matrix(pSCairo.get(), &m);
 578
 579             OSL_TRACE("\r\n:cairocanvas::TextLayout::draw(S,O,p,v,r): Size:(%d,%d), W:%d->%d, Pos (%d,%d), G(%d,%d,%d) %s%s%s%s || Name:%s - %s",
 580                       aFont.GetWidth(),
 581                       aFont.GetHeight(),
 582                       aMetric.GetWidth(),
 583                       nWidth,
 584                       (int) rOutpos.X(),
 585                       (int) rOutpos.Y(),
 586                       cairo_glyphs[0].index, cairo_glyphs[1].index, cairo_glyphs[2].index,
 587                       maLogicalAdvancements.getLength() ? "ADV " : "",
 588                       rSysFontData.bAntialias ? "AA " : "",
 589                       rSysFontData.bFakeBold ? "FB " : "",
 590                       rSysFontData.bFakeItalic ? "FI " : "",
 591     #if (defined CAIRO_HAS_WIN32_SURFACE) && (OSL_DEBUG_LEVEL > 1)
 592                       ::rtl::OUStringToOString( reinterpret_cast<const sal_Unicode*> (logfont.lfFaceName), RTL_TEXTENCODING_UTF8 ).getStr(),
 593     #else
 594                       ::rtl::OUStringToOString( aFont.GetName(), RTL_TEXTENCODING_UTF8 ).getStr(),
 595     #endif
 596                       ::rtl::OUStringToOString( maText.Text.copy( maText.StartPosition, maText.Length ),
 597                                                 RTL_TEXTENCODING_UTF8 ).getStr()
 598                 );
 599
 600             cairo_show_glyphs(pSCairo.get(), &cairo_glyphs[0], cairo_glyphs.size());
 601
 602             //faux bold
 603             if (rSysFontData.bFakeBold) {
 604                 double bold_dx = 0.5 * sqrt( 0.7 * aFont.GetHeight() );
 605                 int total_steps = 2 * ((int) (bold_dx + 0.5));
 606
 607                 // loop to draw the text for every half pixel of displacement
 608                 for (int nSteps = 0; nSteps < total_steps; nSteps++) {
 609                     for(int nGlyphIdx = 0; nGlyphIdx < (int) cairo_glyphs.size(); nGlyphIdx++) {
 610                         cairo_glyphs[nGlyphIdx].x += bold_dx * nSteps / total_steps;
 611                     }
 612                     cairo_show_glyphs(pSCairo.get(), &cairo_glyphs[0], cairo_glyphs.size());
 613                 }
 614                 OSL_TRACE(":cairocanvas::TextLayout::draw(S,O,p,v,r): FAKEBOLD - dx:%d", (int) bold_dx);
 615             }
 616
 617             cairo_restore( pSCairo.get() );
 618             cairo_font_face_destroy(font_face);
 619         }
 620         return true;
 621     }
 622
 623
 624     namespace
 625     {
 626         class OffsetTransformer
 627         {
 628         public:
 629             OffsetTransformer( const ::basegfx::B2DHomMatrix& rMat ) :
 630                 maMatrix( rMat )
 631             {
 632             }
 633
 634             sal_Int32 operator()( const double& rOffset )
 635             {
 636                 // This is an optimization of the normal rMat*[x,0]
 637                 // transformation of the advancement vector (in x
 638                 // direction), followed by a length calculation of the
 639                 // resulting vector: advancement' =
 640                 // ||rMat*[x,0]||. Since advancements are vectors, we
 641                 // can ignore translational components, thus if [x,0],
 642                 // it follows that rMat*[x,0]=[x',0] holds. Thus, we
 643                 // just have to calc the transformation of the x
 644                 // component.
 645
 646                 // TODO(F2): Handle non-horizontal advancements!
 647                 return ::basegfx::fround( hypot(maMatrix.get(0,0)*rOffset,
 648                                                 maMatrix.get(1,0)*rOffset) );
 649             }
 650
 651         private:
 652             ::basegfx::B2DHomMatrix maMatrix;
 653         };
 654     }
 655
 656     void TextLayout::setupTextOffsets( sal_Int32*                       outputOffsets,
 657                                        const uno::Sequence< double >&   inputOffsets,
 658                                        const rendering::ViewState&      viewState,
 659                                        const rendering::RenderState&    renderState     ) const
 660     {
 661         ENSURE_OR_THROW( outputOffsets!=NULL,
 662                           "TextLayout::setupTextOffsets offsets NULL" );
 663
 664         ::basegfx::B2DHomMatrix aMatrix;
 665
 666         ::canvas::tools::mergeViewAndRenderTransform(aMatrix,
 667                                                      viewState,
 668                                                      renderState);
 669
 670         // fill integer offsets
 671         ::std::transform( const_cast< uno::Sequence< double >& >(inputOffsets).getConstArray(),
 672                           const_cast< uno::Sequence< double >& >(inputOffsets).getConstArray()+inputOffsets.getLength(),
 673                           outputOffsets,
 674                           OffsetTransformer( aMatrix ) );
 675     }
 676
 677 #define SERVICE_NAME "com.sun.star.rendering.TextLayout"
 678 #define IMPLEMENTATION_NAME "CairoCanvas::TextLayout"
 679
 680     ::rtl::OUString SAL_CALL TextLayout::getImplementationName() throw( uno::RuntimeException )
 681     {
 682         return ::rtl::OUString( RTL_CONSTASCII_USTRINGPARAM( IMPLEMENTATION_NAME ) );
 683     }
 684
 685     sal_Bool SAL_CALL TextLayout::supportsService( const ::rtl::OUString& ServiceName ) throw( uno::RuntimeException )
 686     {
 687         return ServiceName.equalsAsciiL( RTL_CONSTASCII_STRINGPARAM ( SERVICE_NAME ) );
 688     }
 689
 690     uno::Sequence< ::rtl::OUString > SAL_CALL TextLayout::getSupportedServiceNames()  throw( uno::RuntimeException )
 691     {
 692         uno::Sequence< ::rtl::OUString > aRet(1);
 693         aRet[0] = ::rtl::OUString( RTL_CONSTASCII_USTRINGPARAM ( SERVICE_NAME ) );
 694
 695         return aRet;
 696     }
 697 }