ftobjs.c

奇趣公司比较新的qt/emd版本

    }
    else
      internal->transform_matrix = *matrix;

    /* set transform_flags bit flag 0 if `matrix' isn't the identity */
    if ( ( matrix->xy | matrix->yx ) ||
         matrix->xx != 0x10000L      ||
         matrix->yy != 0x10000L      )
      internal->transform_flags |= 1;

    if ( !delta )
    {
      internal->transform_delta.x = 0;
      internal->transform_delta.y = 0;
      delta = &internal->transform_delta;
    }
    else
      internal->transform_delta = *delta;

    /* set transform_flags bit flag 1 if `delta' isn't the null vector */
    if ( delta->x | delta->y )
      internal->transform_flags |= 2;
  }


  static FT_Renderer
  ft_lookup_glyph_renderer( FT_GlyphSlot  slot );


#ifdef GRID_FIT_METRICS
  static void
  ft_glyphslot_grid_fit_metrics( FT_GlyphSlot  slot,
                                 FT_Bool       vertical )
  {
    FT_Glyph_Metrics*  metrics = &slot->metrics;
    FT_Pos             right, bottom;


    if ( vertical )
    {
      metrics->horiBearingX = FT_PIX_FLOOR( metrics->horiBearingX );
      metrics->horiBearingY = FT_PIX_CEIL ( metrics->horiBearingY );

      right  = FT_PIX_CEIL( metrics->vertBearingX + metrics->width );
      bottom = FT_PIX_CEIL( metrics->vertBearingY + metrics->height );

      metrics->vertBearingX = FT_PIX_FLOOR( metrics->vertBearingX );
      metrics->vertBearingY = FT_PIX_FLOOR( metrics->vertBearingY );

      metrics->width  = right - metrics->vertBearingX;
      metrics->height = bottom - metrics->vertBearingY;
    }
    else
    {
      metrics->vertBearingX = FT_PIX_FLOOR( metrics->vertBearingX );
      metrics->vertBearingY = FT_PIX_FLOOR( metrics->vertBearingY );

      right  = FT_PIX_CEIL ( metrics->horiBearingX + metrics->width );
      bottom = FT_PIX_FLOOR( metrics->horiBearingY - metrics->height );

      metrics->horiBearingX = FT_PIX_FLOOR( metrics->horiBearingX );
      metrics->horiBearingY = FT_PIX_CEIL ( metrics->horiBearingY );

      metrics->width  = right - metrics->horiBearingX;
      metrics->height = metrics->horiBearingY - bottom;
    }

    metrics->horiAdvance = FT_PIX_ROUND( metrics->horiAdvance );
    metrics->vertAdvance = FT_PIX_ROUND( metrics->vertAdvance );
  }
#endif /* GRID_FIT_METRICS */


  /* documentation is in freetype.h */

  FT_EXPORT_DEF( FT_Error )
  FT_Load_Glyph( FT_Face   face,
                 FT_UInt   glyph_index,
                 FT_Int32  load_flags )
  {
    FT_Error      error;
    FT_Driver     driver;
    FT_GlyphSlot  slot;
    FT_Library    library;
    FT_Bool       autohint = 0;
    FT_Module     hinter;


    if ( !face || !face->size || !face->glyph )
      return FT_Err_Invalid_Face_Handle;

    /* The validity test for `glyph_index' is performed by the */
    /* font drivers.                                           */

    slot = face->glyph;
    ft_glyphslot_clear( slot );

    driver  = face->driver;
    library = driver->root.library;
    hinter  = library->auto_hinter;

    /* resolve load flags dependencies */

    if ( load_flags & FT_LOAD_NO_RECURSE )
      load_flags |= FT_LOAD_NO_SCALE         |
                    FT_LOAD_IGNORE_TRANSFORM;

    if ( load_flags & FT_LOAD_NO_SCALE )
    {
      load_flags |= FT_LOAD_NO_HINTING |
                    FT_LOAD_NO_BITMAP;

      load_flags &= ~FT_LOAD_RENDER;
    }

    /*
     * Determine whether we need to auto-hint or not.
     * The general rules are:
     *
     * - Do only auto-hinting if we have a hinter module,
     *   a scalable font format dealing with outlines,
     *   and no transforms except simple slants.
     *
     * - Then, autohint if FT_LOAD_FORCE_AUTOHINT is set
     *   or if we don't have a native font hinter.
     *
     * - Otherwise, auto-hint for LIGHT hinting mode.
     *
     * - Exception: The font requires the unpatented
     *   bytecode interpreter to load properly.
     */

    autohint = 0;
    if ( hinter                                    &&
         ( load_flags & FT_LOAD_NO_HINTING  ) == 0 &&
         ( load_flags & FT_LOAD_NO_AUTOHINT ) == 0 &&
         FT_DRIVER_IS_SCALABLE( driver )           &&
         FT_DRIVER_USES_OUTLINES( driver )         &&
         face->internal->transform_matrix.yy > 0   &&
         face->internal->transform_matrix.yx == 0  )
    {
      if ( ( load_flags & FT_LOAD_FORCE_AUTOHINT ) != 0 ||
           !FT_DRIVER_HAS_HINTER( driver )              )
        autohint = 1;
      else
      {
        FT_Render_Mode  mode = FT_LOAD_TARGET_MODE( load_flags );


        if ( mode == FT_RENDER_MODE_LIGHT             ||
             face->internal->ignore_unpatented_hinter )
          autohint = 1;
      }
    }

    if ( autohint )
    {
      FT_AutoHinter_Service  hinting;


      /* try to load embedded bitmaps first if available            */
      /*                                                            */
      /* XXX: This is really a temporary hack that should disappear */
      /*      promptly with FreeType 2.1!                           */
      /*                                                            */
      if ( FT_HAS_FIXED_SIZES( face )             &&
          ( load_flags & FT_LOAD_NO_BITMAP ) == 0 )
      {
        error = driver->clazz->load_glyph( slot, face->size,
                                           glyph_index,
                                           load_flags | FT_LOAD_SBITS_ONLY );

        if ( !error && slot->format == FT_GLYPH_FORMAT_BITMAP )
          goto Load_Ok;
      }

      /* load auto-hinted outline */
      hinting = (FT_AutoHinter_Service)hinter->clazz->module_interface;

      error   = hinting->load_glyph( (FT_AutoHinter)hinter,
                                     slot, face->size,
                                     glyph_index, load_flags );
    }
    else
    {
      error = driver->clazz->load_glyph( slot,
                                         face->size,
                                         glyph_index,
                                         load_flags );
      if ( error )
        goto Exit;

      if ( slot->format == FT_GLYPH_FORMAT_OUTLINE )
      {
        /* check that the loaded outline is correct */
        error = FT_Outline_Check( &slot->outline );
        if ( error )
          goto Exit;

#ifdef GRID_FIT_METRICS
        if ( !( load_flags & FT_LOAD_NO_HINTING ) )
          ft_glyphslot_grid_fit_metrics( slot,
              FT_BOOL( load_flags & FT_LOAD_VERTICAL_LAYOUT ) );
#endif
      }
    }

  Load_Ok:
    /* compute the advance */
    if ( load_flags & FT_LOAD_VERTICAL_LAYOUT )
    {
      slot->advance.x = 0;
      slot->advance.y = slot->metrics.vertAdvance;
    }
    else
    {
      slot->advance.x = slot->metrics.horiAdvance;
      slot->advance.y = 0;
    }

    /* compute the linear advance in 16.16 pixels */
    if ( ( load_flags & FT_LOAD_LINEAR_DESIGN ) == 0  &&
         ( face->face_flags & FT_FACE_FLAG_SCALABLE ) )
    {
      FT_Size_Metrics*  metrics = &face->size->metrics;


      /* it's tricky! */
      slot->linearHoriAdvance = FT_MulDiv( slot->linearHoriAdvance,
                                           metrics->x_scale, 64 );

      slot->linearVertAdvance = FT_MulDiv( slot->linearVertAdvance,
                                           metrics->y_scale, 64 );
    }

    if ( ( load_flags & FT_LOAD_IGNORE_TRANSFORM ) == 0 )
    {
      FT_Face_Internal  internal = face->internal;


      /* now, transform the glyph image if needed */
      if ( internal->transform_flags )
      {
        /* get renderer */
        FT_Renderer  renderer = ft_lookup_glyph_renderer( slot );


        if ( renderer )
          error = renderer->clazz->transform_glyph(
                                     renderer, slot,
                                     &internal->transform_matrix,
                                     &internal->transform_delta );
        /* transform advance */
        FT_Vector_Transform( &slot->advance, &internal->transform_matrix );
      }
    }

    /* do we need to render the image now? */
    if ( !error                                    &&
         slot->format != FT_GLYPH_FORMAT_BITMAP    &&
         slot->format != FT_GLYPH_FORMAT_COMPOSITE &&
         load_flags & FT_LOAD_RENDER )
    {
      FT_Render_Mode  mode = FT_LOAD_TARGET_MODE( load_flags );


      if ( mode == FT_RENDER_MODE_NORMAL      &&
           (load_flags & FT_LOAD_MONOCHROME ) )
        mode = FT_RENDER_MODE_MONO;

      error = FT_Render_Glyph( slot, mode );
    }

  Exit:
    return error;
  }


  /* documentation is in freetype.h */

  FT_EXPORT_DEF( FT_Error )
  FT_Load_Char( FT_Face   face,
                FT_ULong  char_code,
                FT_Int32  load_flags )
  {
    FT_UInt  glyph_index;


    if ( !face )
      return FT_Err_Invalid_Face_Handle;

    glyph_index = (FT_UInt)char_code;
    if ( face->charmap )
      glyph_index = FT_Get_Char_Index( face, char_code );

    return FT_Load_Glyph( face, glyph_index, load_flags );
  }


  /* destructor for sizes list */
  static void
  destroy_size( FT_Memory  memory,
                FT_Size    size,
                FT_Driver  driver )
  {
    /* finalize client-specific data */
    if ( size->generic.finalizer )
      size->generic.finalizer( size );

    /* finalize format-specific stuff */
    if ( driver->clazz->done_size )
      driver->clazz->done_size( size );

    FT_FREE( size->internal );
    FT_FREE( size );
  }


  static void
  ft_cmap_done_internal( FT_CMap  cmap );


  static void
  destroy_charmaps( FT_Face    face,
                    FT_Memory  memory )
  {
    FT_Int  n;


    for ( n = 0; n < face->num_charmaps; n++ )
    {
      FT_CMap  cmap = FT_CMAP( face->charmaps[n] );


      ft_cmap_done_internal( cmap );

      face->charmaps[n] = NULL;
    }

    FT_FREE( face->charmaps );
    face->num_charmaps = 0;
  }


  /* destructor for faces list */
  static void
  destroy_face( FT_Memory  memory,
                FT_Face    face,
                FT_Driver  driver )
  {
    FT_Driver_Class  clazz = driver->clazz;


    /* discard auto-hinting data */
    if ( face->autohint.finalizer )
      face->autohint.finalizer( face->autohint.data );

    /* Discard glyph slots for this face.                           */
    /* Beware!  FT_Done_GlyphSlot() changes the field `face->glyph' */
    while ( face->glyph )
      FT_Done_GlyphSlot( face->glyph );

    /* discard all sizes for this face */
    FT_List_Finalize( &face->sizes_list,
                      (FT_List_Destructor)destroy_size,
                      memory,
                      driver );
    face->size = 0;

    /* now discard client data */
    if ( face->generic.finalizer )
      face->generic.finalizer( face );

    /* discard charmaps */
    destroy_charmaps( face, memory );

    /* finalize format-specific stuff */
    if ( clazz->done_face )
      clazz->done_face( face );

    /* close the stream for this face if needed */
    FT_Stream_Free(
      face->stream,
      ( face->face_flags & FT_FACE_FLAG_EXTERNAL_STREAM ) != 0 );

    face->stream = 0;

    /* get rid of it */
    if ( face->internal )
    {
      FT_FREE( face->internal );
    }
    FT_FREE( face );
  }


  static void
  Destroy_Driver( FT_Driver  driver )
  {
    FT_List_Finalize( &driver->faces_list,
                      (FT_List_Destructor)destroy_face,
                      driver->root.memory,
                      driver );

    /* check whether we need to drop the driver's glyph loader */
    if ( FT_DRIVER_USES_OUTLINES( driver ) )
      FT_GlyphLoader_Done( driver->glyph_loader );
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    find_unicode_charmap                                               */
  /*                                                                       */
  /* <Description>                                                         */
  /*    This function finds a Unicode charmap, if there is one.            */
  /*    And if there is more than one, it tries to favour the more         */
  /*    extensive one, i.e., one that supports UCS-4 against those which   */
  /*    are limited to the BMP (said UCS-2 encoding.)                      */
  /*                                                                       */
  /*    This function is called from open_face() (just below), and also    */
  /*    from FT_Select_Charmap( ..., FT_ENCODING_UNICODE).                 */
  /*                                                                       */
  static FT_Error
  find_unicode_charmap( FT_Face  face )
  {
    FT_CharMap*  first;
    FT_CharMap*  cur;
    FT_CharMap*  unicmap = NULL;  /* some UCS-2 map, if we found it */


    /* caller should have already checked that `face' is valid */
    FT_ASSERT( face );

    first = face->charmaps;

    if ( !first )
      return FT_Err_Invalid_CharMap_Handle;

    /*
     *  The original TrueType specification(s) only specified charmap
     *  formats that are capable of mapping 8 or 16 bit character codes to
     *  glyph indices.
     *
     *  However, recent updates to the Apple and OpenType specifications
     *  introduced new formats that are capable of mapping 32-bit character
     *  codes as well.  And these are already used on some fonts, mainly to
     *  map non-BMP Asian ideographs as defined in Unicode.
     *
     *  For compatibility purposes, these fonts generally come with
     *  *several* Unicode charmaps:
     *
     *   - One of them in the "old" 16-bit format, that cannot access
     *     all glyphs in the font.
     *
     *   - Another one in the "new" 32-bit format, that can access all
     *     the glyphs.
     *
     *  This function has been written to always favor a 32-bit charmap