aflatin2.c.svn-base

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    }

    if ( !error )
    {
      /* For now, compute the standard width and height from the `o'. */
      af_latin2_metrics_init_widths( metrics, face, 'o' );
      af_latin2_metrics_init_blues( metrics, face );
    }

    FT_Set_Charmap( face, oldmap );
    return AF_Err_Ok;
  }


  static void
  af_latin2_metrics_scale_dim( AF_LatinMetrics  metrics,
                              AF_Scaler        scaler,
                              AF_Dimension     dim )
  {
    FT_Fixed      scale;
    FT_Pos        delta;
    AF_LatinAxis  axis;
    FT_UInt       nn;


    if ( dim == AF_DIMENSION_HORZ )
    {
      scale = scaler->x_scale;
      delta = scaler->x_delta;
    }
    else
    {
      scale = scaler->y_scale;
      delta = scaler->y_delta;
    }

    axis = &metrics->axis[dim];

    if ( axis->org_scale == scale && axis->org_delta == delta )
      return;

    axis->org_scale = scale;
    axis->org_delta = delta;

    /*
     * correct Y scale to optimize the alignment of the top of small
     * letters to the pixel grid
     */
    if ( dim == AF_DIMENSION_VERT )
    {
      AF_LatinAxis  vaxis = &metrics->axis[AF_DIMENSION_VERT];
      AF_LatinBlue  blue = NULL;


      for ( nn = 0; nn < vaxis->blue_count; nn++ )
      {
        if ( vaxis->blues[nn].flags & AF_LATIN_BLUE_ADJUSTMENT )
        {
          blue = &vaxis->blues[nn];
          break;
        }
      }

      if ( blue )
      {
        FT_Pos  scaled = FT_MulFix( blue->shoot.org, scaler->y_scale );
        FT_Pos  fitted = ( scaled + 40 ) & ~63;

#if 1
        if ( scaled != fitted ) {
          scale = FT_MulDiv( scale, fitted, scaled );
          AF_LOG(( "== scaled x-top = %.2g  fitted = %.2g, scaling = %.4g\n", scaled/64.0, fitted/64.0, (fitted*1.0)/scaled ));
        }
#endif
      }
    }

    axis->scale = scale;
    axis->delta = delta;

    if ( dim == AF_DIMENSION_HORZ )
    {
      metrics->root.scaler.x_scale = scale;
      metrics->root.scaler.x_delta = delta;
    }
    else
    {
      metrics->root.scaler.y_scale = scale;
      metrics->root.scaler.y_delta = delta;
    }

    /* scale the standard widths */
    for ( nn = 0; nn < axis->width_count; nn++ )
    {
      AF_Width  width = axis->widths + nn;


      width->cur = FT_MulFix( width->org, scale );
      width->fit = width->cur;
    }

    /* an extra-light axis corresponds to a standard width that is */
    /* smaller than 0.75 pixels                                    */
    axis->extra_light =
      (FT_Bool)( FT_MulFix( axis->standard_width, scale ) < 32 + 8 );

    if ( dim == AF_DIMENSION_VERT )
    {
      /* scale the blue zones */
      for ( nn = 0; nn < axis->blue_count; nn++ )
      {
        AF_LatinBlue  blue = &axis->blues[nn];
        FT_Pos        dist;


        blue->ref.cur   = FT_MulFix( blue->ref.org, scale ) + delta;
        blue->ref.fit   = blue->ref.cur;
        blue->shoot.cur = FT_MulFix( blue->shoot.org, scale ) + delta;
        blue->shoot.fit = blue->shoot.cur;
        blue->flags    &= ~AF_LATIN_BLUE_ACTIVE;

        /* a blue zone is only active if it is less than 3/4 pixels tall */
        dist = FT_MulFix( blue->ref.org - blue->shoot.org, scale );
        if ( dist <= 48 && dist >= -48 )
        {
          FT_Pos  delta1, delta2;

          delta1 = blue->shoot.org - blue->ref.org;
          delta2 = delta1;
          if ( delta1 < 0 )
            delta2 = -delta2;

          delta2 = FT_MulFix( delta2, scale );

          if ( delta2 < 32 )
            delta2 = 0;
          else if ( delta2 < 64 )
            delta2 = 32 + ( ( ( delta2 - 32 ) + 16 ) & ~31 );
          else
            delta2 = FT_PIX_ROUND( delta2 );

          if ( delta1 < 0 )
            delta2 = -delta2;

          blue->ref.fit   = FT_PIX_ROUND( blue->ref.cur );
          blue->shoot.fit = blue->ref.fit + delta2;

          AF_LOG(( ">> activating blue zone %d:  ref.cur=%.2g ref.fit=%.2g shoot.cur=%.2g shoot.fit=%.2g\n",
                   nn, blue->ref.cur/64.0, blue->ref.fit/64.0,
                   blue->shoot.cur/64.0, blue->shoot.fit/64.0 ));

          blue->flags |= AF_LATIN_BLUE_ACTIVE;
        }
      }
    }
  }


  FT_LOCAL_DEF( void )
  af_latin2_metrics_scale( AF_LatinMetrics  metrics,
                          AF_Scaler        scaler )
  {
    metrics->root.scaler.render_mode = scaler->render_mode;
    metrics->root.scaler.face        = scaler->face;

    af_latin2_metrics_scale_dim( metrics, scaler, AF_DIMENSION_HORZ );
    af_latin2_metrics_scale_dim( metrics, scaler, AF_DIMENSION_VERT );
  }


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****           L A T I N   G L Y P H   A N A L Y S I S             *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

#define  SORT_SEGMENTS

  FT_LOCAL_DEF( FT_Error )
  af_latin2_hints_compute_segments( AF_GlyphHints  hints,
                                   AF_Dimension   dim )
  {
    AF_AxisHints  axis          = &hints->axis[dim];
    FT_Memory     memory        = hints->memory;
    FT_Error      error         = AF_Err_Ok;
    AF_Segment    segment       = NULL;
    AF_SegmentRec seg0;
    AF_Point*     contour       = hints->contours;
    AF_Point*     contour_limit = contour + hints->num_contours;
    AF_Direction  major_dir, segment_dir;


    FT_ZERO( &seg0 );
    seg0.score = 32000;
    seg0.flags = AF_EDGE_NORMAL;

    major_dir   = (AF_Direction)FT_ABS( axis->major_dir );
    segment_dir = major_dir;

    axis->num_segments = 0;

    /* set up (u,v) in each point */
    if ( dim == AF_DIMENSION_HORZ )
    {
      AF_Point  point = hints->points;
      AF_Point  limit = point + hints->num_points;


      for ( ; point < limit; point++ )
      {
        point->u = point->fx;
        point->v = point->fy;
      }
    }
    else
    {
      AF_Point  point = hints->points;
      AF_Point  limit = point + hints->num_points;


      for ( ; point < limit; point++ )
      {
        point->u = point->fy;
        point->v = point->fx;
      }
    }

    /* do each contour separately */
    for ( ; contour < contour_limit; contour++ )
    {
      AF_Point  point   =  contour[0];
      AF_Point  start   =  point;
      AF_Point  last    =  point->prev;


      if ( point == last )  /* skip singletons -- just in case */
        continue;

      /* already on an edge ?, backtrack to find its start */
      if ( FT_ABS( point->in_dir ) == major_dir )
      {
        point = point->prev;

        while ( point->in_dir == start->in_dir )
          point = point->prev;
      }
      else  /* otherwise, find first segment start, if any */
      {
        while ( FT_ABS( point->out_dir ) != major_dir )
        {
          point = point->next;

          if ( point == start )
            goto NextContour;
        }
      }

      start = point;

      for  (;;)
      {
        AF_Point  first;
        FT_Pos    min_u, min_v, max_u, max_v;

        /* we're at the start of a new segment */
        FT_ASSERT( FT_ABS( point->out_dir ) == major_dir &&
                           point->in_dir != point->out_dir );
        first = point;

        min_u = max_u = point->u;
        min_v = max_v = point->v;

        point = point->next;

        while ( point->out_dir == first->out_dir )
        {
          point = point->next;

          if ( point->u < min_u )
            min_u = point->u;

          if ( point->u > max_u )
            max_u = point->u;
        }

        if ( point->v < min_v )
          min_v = point->v;

        if ( point->v > max_v )
          max_v = point->v;

        /* record new segment */
        error = af_axis_hints_new_segment( axis, memory, &segment );
        if ( error )
          goto Exit;

        segment[0]         = seg0;
        segment->dir       = first->out_dir;
        segment->first     = first;
        segment->last      = point;
        segment->contour   = contour;
        segment->pos       = (FT_Short)(( min_u + max_u ) >> 1);
        segment->min_coord = (FT_Short) min_v;
        segment->max_coord = (FT_Short) max_v;
        segment->height    = (FT_Short)(max_v - min_v);

        /* a segment is round if it doesn't have successive */
        /* on-curve points.                                 */
        {
          AF_Point  pt   = first;
          AF_Point  last = point;
          AF_Flags  f0   = (AF_Flags)(pt->flags & AF_FLAG_CONTROL);
          AF_Flags  f1;


          segment->flags &= ~AF_EDGE_ROUND;

          for ( ; pt != last; f0 = f1 )
          {
            pt = pt->next;
            f1 = (AF_Flags)(pt->flags & AF_FLAG_CONTROL);

            if ( !f0 && !f1 )
              break;

            if ( pt == last )
              segment->flags |= AF_EDGE_ROUND;
          }
        }

       /* this can happen in the case of a degenerate contour
        * e.g. a 2-point vertical contour
        */
        if ( point == start )
          break;

        /* jump to the start of the next segment, if any */
        while ( FT_ABS(point->out_dir) != major_dir )
        {
          point = point->next;

          if ( point == start )
            goto NextContour;
        }
      }

    NextContour:
      ;
    } /* contours */

    /* now slightly increase the height of segments when this makes */
    /* sense -- this is used to better detect and ignore serifs     */
    {
      AF_Segment  segments     = axis->segments;
      AF_Segment  segments_end = segments + axis->num_segments;


      for ( segment = segments; segment < segments_end; segment++ )
      {
        AF_Point  first   = segment->first;
        AF_Point  last    = segment->last;
        AF_Point  p;
        FT_Pos    first_v = first->v;
        FT_Pos    last_v  = last->v;


        if ( first == last )
          continue;

        if ( first_v < last_v )
        {
          p = first->prev;
          if ( p->v < first_v )
            segment->height = (FT_Short)( segment->height +
                                          ( ( first_v - p->v ) >> 1 ) );

          p = last->next;
          if ( p->v > last_v )
            segment->height = (FT_Short)( segment->height +
                                          ( ( p->v - last_v ) >> 1 ) );
        }
        else
        {
          p = first->prev;
          if ( p->v > first_v )
            segment->height = (FT_Short)( segment->height +
                                          ( ( p->v - first_v ) >> 1 ) );

          p = last->next;
          if ( p->v < last_v )
            segment->height = (FT_Short)( segment->height +
                                          ( ( last_v - p->v ) >> 1 ) );
        }
      }
    }

#ifdef AF_SORT_SEGMENTS
   /* place all segments with a negative direction to the start
    * of the array, used to speed up segment linking later...
    */
    {
      AF_Segment  segments = axis->segments;
      FT_UInt     count    = axis->num_segments;
      FT_UInt     ii, jj;

      for (ii = 0; ii < count; ii++)
      {
        if ( segments[ii].dir > 0 )
        {
          for (jj = ii+1; jj < count; jj++)
          {
            if ( segments[jj].dir < 0 )
            {
              AF_SegmentRec  tmp;

              tmp          = segments[ii];
              segments[ii] = segments[jj];
              segments[jj] = tmp;

              break;
            }
          }

          if ( jj == count )
            break;
        }
      }