afhints.c.svn-base

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        last  = seg->last;
        point = first;
        for (;;)
        {
          point->y      = edge->pos;
          point->flags |= AF_FLAG_TOUCH_Y;

          if ( point == last )
            break;

          point = point->next;
        }
      }
    }
  }


  /****************************************************************
   *
   *                    STRONG POINT INTERPOLATION
   *
   ****************************************************************/


  /* hint the strong points -- this is equivalent to the TrueType `IP' */
  /* hinting instruction                                               */

  FT_LOCAL_DEF( void )
  af_glyph_hints_align_strong_points( AF_GlyphHints  hints,
                                      AF_Dimension   dim )
  {
    AF_Point      points      = hints->points;
    AF_Point      point_limit = points + hints->num_points;
    AF_AxisHints  axis        = &hints->axis[dim];
    AF_Edge       edges       = axis->edges;
    AF_Edge       edge_limit  = edges + axis->num_edges;
    AF_Flags      touch_flag;


    if ( dim == AF_DIMENSION_HORZ )
      touch_flag = AF_FLAG_TOUCH_X;
    else
      touch_flag  = AF_FLAG_TOUCH_Y;

    if ( edges < edge_limit )
    {
      AF_Point  point;
      AF_Edge   edge;


      for ( point = points; point < point_limit; point++ )
      {
        FT_Pos  u, ou, fu;  /* point position */
        FT_Pos  delta;


        if ( point->flags & touch_flag )
          continue;

        /* if this point is candidate to weak interpolation, we       */
        /* interpolate it after all strong points have been processed */

        if (  ( point->flags & AF_FLAG_WEAK_INTERPOLATION ) &&
             !( point->flags & AF_FLAG_INFLECTION )         )
          continue;

        if ( dim == AF_DIMENSION_VERT )
        {
          u  = point->fy;
          ou = point->oy;
        }
        else
        {
          u  = point->fx;
          ou = point->ox;
        }

        fu = u;

        /* is the point before the first edge? */
        edge  = edges;
        delta = edge->fpos - u;
        if ( delta >= 0 )
        {
          u = edge->pos - ( edge->opos - ou );
          goto Store_Point;
        }

        /* is the point after the last edge? */
        edge  = edge_limit - 1;
        delta = u - edge->fpos;
        if ( delta >= 0 )
        {
          u = edge->pos + ( ou - edge->opos );
          goto Store_Point;
        }

        {
          FT_UInt  min, max, mid;
          FT_Pos   fpos;


          /* find enclosing edges */
          min = 0;
          max = edge_limit - edges;

#if 1
          /* for small edge counts, a linear search is better */
          if ( max <= 8 )
          {
            FT_UInt  nn;

            for ( nn = 0; nn < max; nn++ )
              if ( edges[nn].fpos >= u )
                break;

            if ( edges[nn].fpos == u )
            {
              u = edges[nn].pos;
              goto Store_Point;
            }
            min = nn;
          }
          else
#endif
          while ( min < max )
          {
            mid  = ( max + min ) >> 1;
            edge = edges + mid;
            fpos = edge->fpos;

            if ( u < fpos )
              max = mid;
            else if ( u > fpos )
              min = mid + 1;
            else
            {
              /* we are on the edge */
              u = edge->pos;
              goto Store_Point;
            }
          }

          {
            AF_Edge  before = edges + min - 1;
            AF_Edge  after  = edges + min + 0;


            /* assert( before && after && before != after ) */
            if ( before->scale == 0 )
              before->scale = FT_DivFix( after->pos - before->pos,
                                         after->fpos - before->fpos );

            u = before->pos + FT_MulFix( fu - before->fpos,
                                         before->scale );
          }
        }

      Store_Point:
        /* save the point position */
        if ( dim == AF_DIMENSION_HORZ )
          point->x = u;
        else
          point->y = u;

        point->flags |= touch_flag;
      }
    }
  }


  /****************************************************************
   *
   *                    WEAK POINT INTERPOLATION
   *
   ****************************************************************/


  static void
  af_iup_shift( AF_Point  p1,
                AF_Point  p2,
                AF_Point  ref )
  {
    AF_Point  p;
    FT_Pos    delta = ref->u - ref->v;

    if ( delta == 0 )
      return;

    for ( p = p1; p < ref; p++ )
      p->u = p->v + delta;

    for ( p = ref + 1; p <= p2; p++ )
      p->u = p->v + delta;
  }


  static void
  af_iup_interp( AF_Point  p1,
                 AF_Point  p2,
                 AF_Point  ref1,
                 AF_Point  ref2 )
  {
    AF_Point  p;
    FT_Pos    u;
    FT_Pos    v1 = ref1->v;
    FT_Pos    v2 = ref2->v;
    FT_Pos    d1 = ref1->u - v1;
    FT_Pos    d2 = ref2->u - v2;


    if ( p1 > p2 )
      return;

    if ( v1 == v2 )
    {
      for ( p = p1; p <= p2; p++ )
      {
        u = p->v;

        if ( u <= v1 )
          u += d1;
        else
          u += d2;

        p->u = u;
      }
      return;
    }

    if ( v1 < v2 )
    {
      for ( p = p1; p <= p2; p++ )
      {
        u = p->v;

        if ( u <= v1 )
          u += d1;
        else if ( u >= v2 )
          u += d2;
        else
          u = ref1->u + FT_MulDiv( u - v1, ref2->u - ref1->u, v2 - v1 );

        p->u = u;
      }
    }
    else
    {
      for ( p = p1; p <= p2; p++ )
      {
        u = p->v;

        if ( u <= v2 )
          u += d2;
        else if ( u >= v1 )
          u += d1;
        else
          u = ref1->u + FT_MulDiv( u - v1, ref2->u - ref1->u, v2 - v1 );

        p->u = u;
      }
    }
  }


  FT_LOCAL_DEF( void )
  af_glyph_hints_align_weak_points( AF_GlyphHints  hints,
                                    AF_Dimension   dim )
  {
    AF_Point   points        = hints->points;
    AF_Point   point_limit   = points + hints->num_points;
    AF_Point*  contour       = hints->contours;
    AF_Point*  contour_limit = contour + hints->num_contours;
    AF_Flags   touch_flag;
    AF_Point   point;
    AF_Point   end_point;
    AF_Point   first_point;


    /* PASS 1: Move segment points to edge positions */

    if ( dim == AF_DIMENSION_HORZ )
    {
      touch_flag = AF_FLAG_TOUCH_X;

      for ( point = points; point < point_limit; point++ )
      {
        point->u = point->x;
        point->v = point->ox;
      }
    }
    else
    {
      touch_flag = AF_FLAG_TOUCH_Y;

      for ( point = points; point < point_limit; point++ )
      {
        point->u = point->y;
        point->v = point->oy;
      }
    }

    point = points;

    for ( ; contour < contour_limit; contour++ )
    {
      AF_Point  first_touched, last_touched;


      point       = *contour;
      end_point   = point->prev;
      first_point = point;

      /* find first touched point */
      for (;;)
      {
        if ( point > end_point )  /* no touched point in contour */
          goto NextContour;

        if ( point->flags & touch_flag )
          break;

        point++;
      }

      first_touched = point;
      last_touched  = point;

      for (;;)
      {
        FT_ASSERT( point <= end_point &&
                   ( point->flags & touch_flag ) != 0 );

        /* skip any touched neighbhours */
        while ( point < end_point && ( point[1].flags & touch_flag ) != 0 )
          point++;

        last_touched = point;

        /* find the next touched point, if any */
        point ++;
        for (;;)
        {
          if ( point > end_point )
            goto EndContour;

          if ( ( point->flags & touch_flag ) != 0 )
            break;

          point++;
        }

        /* interpolate between last_touched and point */
        af_iup_interp( last_touched + 1, point - 1,
                       last_touched, point );
      }

    EndContour:
      /* special case: only one point was touched */
      if ( last_touched == first_touched )
      {
        af_iup_shift( first_point, end_point, first_touched );
      }
      else /* interpolate the last part */
      {
        if ( last_touched < end_point )
          af_iup_interp( last_touched + 1, end_point,
                         last_touched, first_touched );

        if ( first_touched > points )
          af_iup_interp( first_point, first_touched - 1,
                         last_touched, first_touched );
      }

    NextContour:
      ;
    }

    /* now save the interpolated values back to x/y */
    if ( dim == AF_DIMENSION_HORZ )
    {
      for ( point = points; point < point_limit; point++ )
        point->x = point->u;
    }
    else
    {
      for ( point = points; point < point_limit; point++ )
        point->y = point->u;
    }
  }


#ifdef AF_USE_WARPER

  FT_LOCAL_DEF( void )
  af_glyph_hints_scale_dim( AF_GlyphHints  hints,
                            AF_Dimension   dim,
                            FT_Fixed       scale,
                            FT_Pos         delta )
  {
    AF_Point  points       = hints->points;
    AF_Point  points_limit = points + hints->num_points;
    AF_Point  point;


    if ( dim == AF_DIMENSION_HORZ )
    {
      for ( point = points; point < points_limit; point++ )
        point->x = FT_MulFix( point->fx, scale ) + delta;
    }
    else
    {
      for ( point = points; point < points_limit; point++ )
        point->y = FT_MulFix( point->fy, scale ) + delta;
    }
  }

#endif /* AF_USE_WARPER */

/* END */