ttgload.c

winNT技术操作系统,国外开放的原代码和LIUX一样

    vec       = gloader->current.outline.points;
    vec_limit = vec + n_points;
    flag      = (FT_Byte*)outline->tags;
    x         = 0;

    for ( ; vec < vec_limit; vec++, flag++ )
    {
      FT_Pos  y = 0;


      if ( *flag & 4 )
      {
        if ( p  +1 > limit )
          goto Invalid_Outline;

        y = (FT_Pos)FT_NEXT_BYTE( p );
        if ( ( *flag & 32 ) == 0 )
          y = -y;
      }
      else if ( ( *flag & 32 ) == 0 )
      {
        if ( p + 2 > limit )
          goto Invalid_Outline;

        y = (FT_Pos)FT_NEXT_SHORT( p );
      }

      x     += y;
      vec->y = x;
    }

    /* clear the touch tags */
    for ( n = 0; n < n_points; n++ )
      outline->tags[n] &= FT_CURVE_TAG_ON;

    outline->n_points   = (FT_UShort)n_points;
    outline->n_contours = (FT_Short) n_contours;

    load->cursor = p;

  Fail:
    return error;

  Invalid_Outline:
    error = TT_Err_Invalid_Outline;
    goto Fail;
  }


  FT_CALLBACK_DEF( FT_Error )
  TT_Load_Composite_Glyph( TT_Loader  loader )
  {
    FT_Error        error;
    FT_Byte*        p       = loader->cursor;
    FT_Byte*        limit   = loader->limit;
    FT_GlyphLoader  gloader = loader->gloader;
    FT_SubGlyph     subglyph;
    FT_UInt         num_subglyphs;


    num_subglyphs = 0;

    do
    {
      FT_Fixed  xx, xy, yy, yx;
      FT_UInt   count;


      /* check that we can load a new subglyph */
      error = FT_GlyphLoader_CheckSubGlyphs( gloader, num_subglyphs + 1 );
      if ( error )
        goto Fail;

      /* check space */
      if ( p + 4 > limit )
        goto Invalid_Composite;

      subglyph = gloader->current.subglyphs + num_subglyphs;

      subglyph->arg1 = subglyph->arg2 = 0;

      subglyph->flags = FT_NEXT_USHORT( p );
      subglyph->index = FT_NEXT_USHORT( p );

      /* check space */
      count = 2;
      if ( subglyph->flags & ARGS_ARE_WORDS )
        count += 2;
      if ( subglyph->flags & WE_HAVE_A_SCALE )
        count += 2;
      else if ( subglyph->flags & WE_HAVE_AN_XY_SCALE )
        count += 4;
      else if ( subglyph->flags & WE_HAVE_A_2X2 )
        count += 8;

      if ( p + count > limit )
        goto Invalid_Composite;

      /* read arguments */
      if ( subglyph->flags & ARGS_ARE_WORDS )
      {
        subglyph->arg1 = FT_NEXT_SHORT( p );
        subglyph->arg2 = FT_NEXT_SHORT( p );
      }
      else
      {
        subglyph->arg1 = FT_NEXT_CHAR( p );
        subglyph->arg2 = FT_NEXT_CHAR( p );
      }

      /* read transform */
      xx = yy = 0x10000L;
      xy = yx = 0;

      if ( subglyph->flags & WE_HAVE_A_SCALE )
      {
        xx = (FT_Fixed)FT_NEXT_SHORT( p ) << 2;
        yy = xx;
      }
      else if ( subglyph->flags & WE_HAVE_AN_XY_SCALE )
      {
        xx = (FT_Fixed)FT_NEXT_SHORT( p ) << 2;
        yy = (FT_Fixed)FT_NEXT_SHORT( p ) << 2;
      }
      else if ( subglyph->flags & WE_HAVE_A_2X2 )
      {
        xx = (FT_Fixed)FT_NEXT_SHORT( p ) << 2;
        yx = (FT_Fixed)FT_NEXT_SHORT( p ) << 2;
        xy = (FT_Fixed)FT_NEXT_SHORT( p ) << 2;
        yy = (FT_Fixed)FT_NEXT_SHORT( p ) << 2;
      }

      subglyph->transform.xx = xx;
      subglyph->transform.xy = xy;
      subglyph->transform.yx = yx;
      subglyph->transform.yy = yy;

      num_subglyphs++;

    } while ( subglyph->flags & MORE_COMPONENTS );

    gloader->current.num_subglyphs = num_subglyphs;

#ifdef TT_USE_BYTECODE_INTERPRETER

    {
      FT_Stream  stream = loader->stream;


      /* we must undo the FT_FRAME_ENTER in order to point to the */
      /* composite instructions, if we find some.               */
      /* we will process them later...                          */
      /*                                                        */
      loader->ins_pos = (FT_ULong)( FT_STREAM_POS() +
                                    p - limit );
    }

#endif

    loader->cursor = p;

  Fail:
    return error;

  Invalid_Composite:
    error = TT_Err_Invalid_Composite;
    goto Fail;
  }


  FT_LOCAL_DEF( void )
  TT_Init_Glyph_Loading( TT_Face  face )
  {
    face->access_glyph_frame   = TT_Access_Glyph_Frame;
    face->read_glyph_header    = TT_Load_Glyph_Header;
    face->read_simple_glyph    = TT_Load_Simple_Glyph;
    face->read_composite_glyph = TT_Load_Composite_Glyph;
    face->forget_glyph_frame   = TT_Forget_Glyph_Frame;
  }


  static void
  tt_prepare_zone( TT_GlyphZone  zone,
                   FT_GlyphLoad  load,
                   FT_UInt       start_point,
                   FT_UInt       start_contour )
  {
    zone->n_points   = (FT_UShort)( load->outline.n_points - start_point );
    zone->n_contours = (FT_Short) ( load->outline.n_contours - start_contour );
    zone->org        = load->extra_points + start_point;
    zone->cur        = load->outline.points + start_point;
    zone->orus       = load->extra_points2 + start_point;
    zone->tags       = (FT_Byte*)load->outline.tags + start_point;
    zone->contours   = (FT_UShort*)load->outline.contours + start_contour;
    zone->first_point = (FT_UShort)start_point;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Hint_Glyph                                                      */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Hint the glyph using the zone prepared by the caller.  Note that   */
  /*    the zone is supposed to include four phantom points.               */
  /*                                                                       */
  static FT_Error
  TT_Hint_Glyph( TT_Loader  loader,
                 FT_Bool    is_composite )
  {
    TT_GlyphZone  zone = &loader->zone;
    FT_Pos        origin;

#ifdef TT_USE_BYTECODE_INTERPRETER
    FT_UInt       n_ins;
#else
    FT_UNUSED( is_composite );
#endif


#ifdef TT_USE_BYTECODE_INTERPRETER
    n_ins = loader->glyph->control_len;
#endif

    origin = zone->cur[zone->n_points - 4].x;
    origin = FT_PIX_ROUND( origin ) - origin;
    if ( origin )
      translate_array( zone->n_points, zone->cur, origin, 0 );

#ifdef TT_USE_BYTECODE_INTERPRETER
    /* save original point positioin in org */
    if ( n_ins > 0 )
      FT_ARRAY_COPY( zone->org, zone->cur, zone->n_points );
#endif

    /* round pp2 and pp4 */
    zone->cur[zone->n_points - 3].x =
      FT_PIX_ROUND( zone->cur[zone->n_points - 3].x );
    zone->cur[zone->n_points - 1].y =
      FT_PIX_ROUND( zone->cur[zone->n_points - 1].y );

#ifdef TT_USE_BYTECODE_INTERPRETER

    if ( n_ins > 0 )
    {
      FT_Bool   debug;
      FT_Error  error;


      error = TT_Set_CodeRange( loader->exec, tt_coderange_glyph,
                                loader->exec->glyphIns, n_ins );
      if ( error )
        return error;

      loader->exec->is_composite = is_composite;
      loader->exec->pts          = *zone;

      debug = FT_BOOL( !( loader->load_flags & FT_LOAD_NO_SCALE ) &&
                       ((TT_Size)loader->size)->debug             );

      error = TT_Run_Context( loader->exec, debug );
      if ( error && loader->exec->pedantic_hinting )
        return error;
    }

#endif

    /* save glyph phantom points */
    if ( !loader->preserve_pps )
    {
      loader->pp1 = zone->cur[zone->n_points - 4];
      loader->pp2 = zone->cur[zone->n_points - 3];
      loader->pp3 = zone->cur[zone->n_points - 2];
      loader->pp4 = zone->cur[zone->n_points - 1];
    }

    return TT_Err_Ok;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Process_Simple_Glyph                                            */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Once a simple glyph has been loaded, it needs to be processed.     */
  /*    Usually, this means scaling and hinting through bytecode           */
  /*    interpretation.                                                    */
  /*                                                                       */
  static FT_Error
  TT_Process_Simple_Glyph( TT_Loader  loader )
  {
    FT_GlyphLoader  gloader = loader->gloader;
    FT_Error        error   = TT_Err_Ok;
    FT_Outline*     outline;
    FT_UInt         n_points;


    outline  = &gloader->current.outline;
    n_points = outline->n_points;

    /* set phantom points */

    outline->points[n_points    ] = loader->pp1;
    outline->points[n_points + 1] = loader->pp2;
    outline->points[n_points + 2] = loader->pp3;
    outline->points[n_points + 3] = loader->pp4;

    outline->tags[n_points    ] = 0;
    outline->tags[n_points + 1] = 0;
    outline->tags[n_points + 2] = 0;
    outline->tags[n_points + 3] = 0;

    n_points += 4;

#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT

    if ( ((TT_Face)loader->face)->doblend )
    {
      /* Deltas apply to the unscaled data. */
      FT_Vector*  deltas;
      FT_Memory   memory = loader->face->memory;
      FT_UInt     i;


      error = TT_Vary_Get_Glyph_Deltas( (TT_Face)(loader->face),
                                        loader->glyph_index,
                                        &deltas,
                                        n_points );
      if ( error )
        return error;

      for ( i = 0; i < n_points; ++i )
      {
        outline->points[i].x += deltas[i].x;
        outline->points[i].y += deltas[i].y;
      }

      FT_FREE( deltas );
    }

#endif /* TT_CONFIG_OPTION_GX_VAR_SUPPORT */

    if ( IS_HINTED( loader->load_flags ) )
    {
      tt_prepare_zone( &loader->zone, &gloader->current, 0, 0 );

      FT_ARRAY_COPY( loader->zone.orus, loader->zone.cur,
                     loader->zone.n_points + 4 );
    }

    /* scale the glyph */
    if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 )
    {
      FT_Vector*  vec     = outline->points;
      FT_Vector*  limit   = outline->points + n_points;
      FT_Fixed    x_scale = ((TT_Size)loader->size)->metrics.x_scale;
      FT_Fixed    y_scale = ((TT_Size)loader->size)->metrics.y_scale;


      for ( ; vec < limit; vec++ )
      {
        vec->x = FT_MulFix( vec->x, x_scale );
        vec->y = FT_MulFix( vec->y, y_scale );
      }

      loader->pp1 = outline->points[n_points - 4];
      loader->pp2 = outline->points[n_points - 3];
      loader->pp3 = outline->points[n_points - 2];
      loader->pp4 = outline->points[n_points - 1];
    }

    if ( IS_HINTED( loader->load_flags ) )
    {
      loader->zone.n_points += 4;

      error = TT_Hint_Glyph( loader, 0 );
    }

    return error;
  }