aflatin.h File Reference

#include "afhints.h"

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Classes
struct	AF_LatinBlueRec_
struct	AF_LatinAxisRec_
struct	AF_LatinMetricsRec_

Macros
#define	AF_LATIN_CONSTANT(metrics, c)    ( ( (c) * (FT_Long)( (AF_LatinMetrics)(metrics) )->units_per_em ) / 2048 )
#define	AF_LATIN_IS_TOP_BLUE(b)    ( (b)->properties & AF_BLUE_PROPERTY_LATIN_TOP )
#define	AF_LATIN_IS_SUB_TOP_BLUE(b)    ( (b)->properties & AF_BLUE_PROPERTY_LATIN_SUB_TOP )
#define	AF_LATIN_IS_NEUTRAL_BLUE(b)    ( (b)->properties & AF_BLUE_PROPERTY_LATIN_NEUTRAL )
#define	AF_LATIN_IS_X_HEIGHT_BLUE(b)    ( (b)->properties & AF_BLUE_PROPERTY_LATIN_X_HEIGHT )
#define	AF_LATIN_IS_LONG_BLUE(b)    ( (b)->properties & AF_BLUE_PROPERTY_LATIN_LONG )
#define	AF_LATIN_MAX_WIDTHS   16
#define	AF_LATIN_BLUE_ACTIVE   ( 1U << 0 ) /* zone height is <= 3/4px */
#define	AF_LATIN_BLUE_TOP   ( 1U << 1 ) /* we have a top blue zone */
#define	AF_LATIN_BLUE_SUB_TOP   ( 1U << 2 ) /* we have a subscript top */
#define	AF_LATIN_BLUE_NEUTRAL   ( 1U << 3 ) /* we have neutral blue zone */
#define	AF_LATIN_BLUE_ADJUSTMENT   ( 1U << 4 ) /* used for scale adjustment */
#define	AF_LATIN_HINTS_HORZ_SNAP   ( 1U << 0 ) /* stem width snapping */
#define	AF_LATIN_HINTS_VERT_SNAP   ( 1U << 1 ) /* stem height snapping */
#define	AF_LATIN_HINTS_STEM_ADJUST   ( 1U << 2 ) /* stem width/height */
#define	AF_LATIN_HINTS_MONO   ( 1U << 3 ) /* monochrome rendering */
#define	AF_LATIN_HINTS_DO_HORZ_SNAP(h)    AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_HORZ_SNAP )
#define	AF_LATIN_HINTS_DO_VERT_SNAP(h)    AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_VERT_SNAP )
#define	AF_LATIN_HINTS_DO_STEM_ADJUST(h)    AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_STEM_ADJUST )
#define	AF_LATIN_HINTS_DO_MONO(h)    AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_MONO )

Typedefs
typedef struct AF_LatinBlueRec_	AF_LatinBlueRec
typedef struct AF_LatinBlueRec_ *	AF_LatinBlue
typedef struct AF_LatinAxisRec_	AF_LatinAxisRec
typedef struct AF_LatinAxisRec_ *	AF_LatinAxis
typedef struct AF_LatinMetricsRec_	AF_LatinMetricsRec
typedef struct AF_LatinMetricsRec_ *	AF_LatinMetrics

Functions
	af_latin_metrics_init (AF_LatinMetrics metrics, FT_Face face)
	af_latin_metrics_scale (AF_LatinMetrics metrics, AF_Scaler scaler)
	af_latin_metrics_init_widths (AF_LatinMetrics metrics, FT_Face face)
	af_latin_metrics_check_digits (AF_LatinMetrics metrics, FT_Face face)
	af_latin_hints_compute_segments (AF_GlyphHints hints, AF_Dimension dim)
	af_latin_hints_link_segments (AF_GlyphHints hints, FT_UInt width_count, AF_WidthRec *widths, AF_Dimension dim)
	af_latin_hints_compute_edges (AF_GlyphHints hints, AF_Dimension dim)
	af_latin_hints_detect_features (AF_GlyphHints hints, FT_UInt width_count, AF_WidthRec *widths, AF_Dimension dim)

Macro Definition Documentation

AF_LATIN_BLUE_ACTIVE

#define AF_LATIN_BLUE_ACTIVE   ( 1U << 0 ) /* zone height is <= 3/4px */

Definition at line 68 of file aflatin.h.

AF_LATIN_BLUE_ADJUSTMENT

#define AF_LATIN_BLUE_ADJUSTMENT   ( 1U << 4 ) /* used for scale adjustment */

Definition at line 73 of file aflatin.h.

AF_LATIN_BLUE_NEUTRAL

#define AF_LATIN_BLUE_NEUTRAL   ( 1U << 3 ) /* we have neutral blue zone */

Definition at line 72 of file aflatin.h.

AF_LATIN_BLUE_SUB_TOP

#define AF_LATIN_BLUE_SUB_TOP   ( 1U << 2 ) /* we have a subscript top */

Definition at line 70 of file aflatin.h.

AF_LATIN_BLUE_TOP

#define AF_LATIN_BLUE_TOP   ( 1U << 1 ) /* we have a top blue zone */

Definition at line 69 of file aflatin.h.

AF_LATIN_CONSTANT

#define AF_LATIN_CONSTANT	(		metrics,
			c
	)		( ( (c) * (FT_Long)( (AF_LatinMetrics)(metrics) )->units_per_em ) / 2048 )

Definition at line 34 of file aflatin.h.

AF_LATIN_HINTS_DO_HORZ_SNAP

#define AF_LATIN_HINTS_DO_HORZ_SNAP

(

h

)

AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_HORZ_SNAP )

Definition at line 150 of file aflatin.h.

AF_LATIN_HINTS_DO_MONO

#define AF_LATIN_HINTS_DO_MONO

(

h

)

AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_MONO )

Definition at line 159 of file aflatin.h.

AF_LATIN_HINTS_DO_STEM_ADJUST

#define AF_LATIN_HINTS_DO_STEM_ADJUST

(

h

)

AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_STEM_ADJUST )

Definition at line 156 of file aflatin.h.

AF_LATIN_HINTS_DO_VERT_SNAP

#define AF_LATIN_HINTS_DO_VERT_SNAP

(

h

)

AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_VERT_SNAP )

Definition at line 153 of file aflatin.h.

AF_LATIN_HINTS_HORZ_SNAP

#define AF_LATIN_HINTS_HORZ_SNAP   ( 1U << 0 ) /* stem width snapping */

Definition at line 143 of file aflatin.h.

AF_LATIN_HINTS_MONO

#define AF_LATIN_HINTS_MONO   ( 1U << 3 ) /* monochrome rendering */

Definition at line 147 of file aflatin.h.

AF_LATIN_HINTS_STEM_ADJUST

#define AF_LATIN_HINTS_STEM_ADJUST   ( 1U << 2 ) /* stem width/height */

Definition at line 145 of file aflatin.h.

AF_LATIN_HINTS_VERT_SNAP

#define AF_LATIN_HINTS_VERT_SNAP   ( 1U << 1 ) /* stem height snapping */

Definition at line 144 of file aflatin.h.

AF_LATIN_IS_LONG_BLUE

#define AF_LATIN_IS_LONG_BLUE

(

b

)

( (b)->properties & AF_BLUE_PROPERTY_LATIN_LONG )

Definition at line 62 of file aflatin.h.

AF_LATIN_IS_NEUTRAL_BLUE

#define AF_LATIN_IS_NEUTRAL_BLUE

(

b

)

( (b)->properties & AF_BLUE_PROPERTY_LATIN_NEUTRAL )

Definition at line 58 of file aflatin.h.

AF_LATIN_IS_SUB_TOP_BLUE

#define AF_LATIN_IS_SUB_TOP_BLUE

(

b

)

( (b)->properties & AF_BLUE_PROPERTY_LATIN_SUB_TOP )

Definition at line 56 of file aflatin.h.

AF_LATIN_IS_TOP_BLUE

#define AF_LATIN_IS_TOP_BLUE

(

b

)

( (b)->properties & AF_BLUE_PROPERTY_LATIN_TOP )

Definition at line 54 of file aflatin.h.

AF_LATIN_IS_X_HEIGHT_BLUE

#define AF_LATIN_IS_X_HEIGHT_BLUE

(

b

)

( (b)->properties & AF_BLUE_PROPERTY_LATIN_X_HEIGHT )

Definition at line 60 of file aflatin.h.

AF_LATIN_MAX_WIDTHS

#define AF_LATIN_MAX_WIDTHS   16

Definition at line 65 of file aflatin.h.

Typedef Documentation

AF_LatinAxis

typedef struct AF_LatinAxisRec_ * AF_LatinAxis

AF_LatinAxisRec

typedef struct AF_LatinAxisRec_ AF_LatinAxisRec

AF_LatinBlue

typedef struct AF_LatinBlueRec_ * AF_LatinBlue

AF_LatinBlueRec

typedef struct AF_LatinBlueRec_ AF_LatinBlueRec

AF_LatinMetrics

typedef struct AF_LatinMetricsRec_ * AF_LatinMetrics

AF_LatinMetricsRec

typedef struct AF_LatinMetricsRec_ AF_LatinMetricsRec

Function Documentation

af_latin_hints_compute_edges()

af_latin_hints_compute_edges	(	AF_GlyphHints	hints,
		AF_Dimension	dim
	)

Definition at line 2088 of file aflatin.c.

  {
    AF_AxisHints  axis   = &hints->axis[dim];
    FT_Error      error  = FT_Err_Ok;
    FT_Memory     memory = hints->memory;
    AF_LatinAxis  laxis  = &((AF_LatinMetrics)hints->metrics)->axis[dim];
 
    AF_StyleClass   style_class  = hints->metrics->style_class;
    AF_ScriptClass  script_class = af_script_classes[style_class->script];
 
    FT_Bool  top_to_bottom_hinting = 0;
 
    AF_Segment    segments      = axis->segments;
    AF_Segment    segment_limit = segments + axis->num_segments;
    AF_Segment    seg;
 
#if 0
    AF_Direction  up_dir;
#endif
    FT_Fixed      scale;
    FT_Pos        edge_distance_threshold;
    FT_Pos        segment_length_threshold;
    FT_Pos        segment_width_threshold;
 
 
    axis->num_edges = 0;
 
    scale = ( dim == AF_DIMENSION_HORZ ) ? hints->x_scale
                                         : hints->y_scale;
 
#if 0
    up_dir = ( dim == AF_DIMENSION_HORZ ) ? AF_DIR_UP
                                          : AF_DIR_RIGHT;
#endif
 
    if ( dim == AF_DIMENSION_VERT )
      top_to_bottom_hinting = script_class->top_to_bottom_hinting;
 
    /*
     * We ignore all segments that are less than 1 pixel in length
     * to avoid many problems with serif fonts.  We compute the
     * corresponding threshold in font units.
     */
    if ( dim == AF_DIMENSION_HORZ )
      segment_length_threshold = FT_DivFix( 64, hints->y_scale );
    else
      segment_length_threshold = 0;
 
    /*
     * Similarly, we ignore segments that have a width delta
     * larger than 0.5px (i.e., a width larger than 1px).
     */
    segment_width_threshold = FT_DivFix( 32, scale );
 
    /**********************************************************************
     *
     * We begin by generating a sorted table of edges for the current
     * direction.  To do so, we simply scan each segment and try to find
     * an edge in our table that corresponds to its position.
     *
     * If no edge is found, we create and insert a new edge in the
     * sorted table.  Otherwise, we simply add the segment to the edge's
     * list which gets processed in the second step to compute the
     * edge's properties.
     *
     * Note that the table of edges is sorted along the segment/edge
     * position.
     *
     */
 
    /* assure that edge distance threshold is at most 0.25px */
    edge_distance_threshold = FT_MulFix( laxis->edge_distance_threshold,
                                         scale );
    if ( edge_distance_threshold > 64 / 4 )
      edge_distance_threshold = 64 / 4;
 
    edge_distance_threshold = FT_DivFix( edge_distance_threshold,
                                         scale );
 
    for ( seg = segments; seg < segment_limit; seg++ )
    {
      AF_Edge  found = NULL;
      FT_Int   ee;
 
 
      /* ignore too short segments, too wide ones, and, in this loop, */
      /* one-point segments without a direction                       */
      if ( seg->height < segment_length_threshold ||
           seg->delta > segment_width_threshold   ||
           seg->dir == AF_DIR_NONE                )
        continue;
 
      /* A special case for serif edges: If they are smaller than */
      /* 1.5 pixels we ignore them.                               */
      if ( seg->serif                                     &&
           2 * seg->height < 3 * segment_length_threshold )
        continue;
 
      /* look for an edge corresponding to the segment */
      for ( ee = 0; ee < axis->num_edges; ee++ )
      {
        AF_Edge  edge = axis->edges + ee;
        FT_Pos   dist;
 
 
        dist = seg->pos - edge->fpos;
        if ( dist < 0 )
          dist = -dist;
 
        if ( dist < edge_distance_threshold && edge->dir == seg->dir )
        {
          found = edge;
          break;
        }
      }
 
      if ( !found )
      {
        AF_Edge  edge;
 
 
        /* insert a new edge in the list and */
        /* sort according to the position    */
        error = af_axis_hints_new_edge( axis, seg->pos,
                                        (AF_Direction)seg->dir,
                                        top_to_bottom_hinting,
                                        memory, &edge );
        if ( error )
          goto Exit;
 
        /* add the segment to the new edge's list */
        FT_ZERO( edge );
 
        edge->first    = seg;
        edge->last     = seg;
        edge->dir      = seg->dir;
        edge->fpos     = seg->pos;
        edge->opos     = FT_MulFix( seg->pos, scale );
        edge->pos      = edge->opos;
        seg->edge_next = seg;
      }
      else
      {
        /* if an edge was found, simply add the segment to the edge's */
        /* list                                                       */
        seg->edge_next         = found->first;
        found->last->edge_next = seg;
        found->last            = seg;
      }
    }
 
    /* we loop again over all segments to catch one-point segments   */
    /* without a direction: if possible, link them to existing edges */
    for ( seg = segments; seg < segment_limit; seg++ )
    {
      AF_Edge  found = NULL;
      FT_Int   ee;
 
 
      if ( seg->dir != AF_DIR_NONE )
        continue;
 
      /* look for an edge corresponding to the segment */
      for ( ee = 0; ee < axis->num_edges; ee++ )
      {
        AF_Edge  edge = axis->edges + ee;
        FT_Pos   dist;
 
 
        dist = seg->pos - edge->fpos;
        if ( dist < 0 )
          dist = -dist;
 
        if ( dist < edge_distance_threshold )
        {
          found = edge;
          break;
        }
      }
 
      /* one-point segments without a match are ignored */
      if ( found )
      {
        seg->edge_next         = found->first;
        found->last->edge_next = seg;
        found->last            = seg;
      }
    }
 
 
    /*******************************************************************
     *
     * Good, we now compute each edge's properties according to the
     * segments found on its position.  Basically, these are
     *
     * - the edge's main direction
     * - stem edge, serif edge or both (which defaults to stem then)
     * - rounded edge, straight or both (which defaults to straight)
     * - link for edge
     *
     */
 
    /* first of all, set the `edge' field in each segment -- this is */
    /* required in order to compute edge links                       */
 
    /*
     * Note that removing this loop and setting the `edge' field of each
     * segment directly in the code above slows down execution speed for
     * some reasons on platforms like the Sun.
     */
    {
      AF_Edge  edges      = axis->edges;
      AF_Edge  edge_limit = edges + axis->num_edges;
      AF_Edge  edge;
 
 
      for ( edge = edges; edge < edge_limit; edge++ )
      {
        seg = edge->first;
        if ( seg )
          do
          {
            seg->edge = edge;
            seg       = seg->edge_next;
 
          } while ( seg != edge->first );
      }
 
      /* now compute each edge properties */
      for ( edge = edges; edge < edge_limit; edge++ )
      {
        FT_Int  is_round    = 0;  /* does it contain round segments?    */
        FT_Int  is_straight = 0;  /* does it contain straight segments? */
#if 0
        FT_Pos  ups         = 0;  /* number of upwards segments         */
        FT_Pos  downs       = 0;  /* number of downwards segments       */
#endif
 
 
        seg = edge->first;
 
        do
        {
          FT_Bool  is_serif;
 
 
          /* check for roundness of segment */
          if ( seg->flags & AF_EDGE_ROUND )
            is_round++;
          else
            is_straight++;
 
#if 0
          /* check for segment direction */
          if ( seg->dir == up_dir )
            ups   += seg->max_coord - seg->min_coord;
          else
            downs += seg->max_coord - seg->min_coord;
#endif
 
          /* check for links -- if seg->serif is set, then seg->link must */
          /* be ignored                                                   */
          is_serif = FT_BOOL( seg->serif               &&
                              seg->serif->edge         &&
                              seg->serif->edge != edge );
 
          if ( ( seg->link && seg->link->edge ) || is_serif )
          {
            AF_Edge     edge2;
            AF_Segment  seg2;
 
 
            edge2 = edge->link;
            seg2  = seg->link;
 
            if ( is_serif )
            {
              seg2  = seg->serif;
              edge2 = edge->serif;
            }
 
            if ( edge2 )
            {
              FT_Pos  edge_delta;
              FT_Pos  seg_delta;
 
 
              edge_delta = edge->fpos - edge2->fpos;
              if ( edge_delta < 0 )
                edge_delta = -edge_delta;
 
              seg_delta = seg->pos - seg2->pos;
              if ( seg_delta < 0 )
                seg_delta = -seg_delta;
 
              if ( seg_delta < edge_delta )
                edge2 = seg2->edge;
            }
            else
              edge2 = seg2->edge;
 
            if ( is_serif )
            {
              edge->serif   = edge2;
              edge2->flags |= AF_EDGE_SERIF;
            }
            else
              edge->link  = edge2;
          }
 
          seg = seg->edge_next;
 
        } while ( seg != edge->first );
 
        /* set the round/straight flags */
        edge->flags = AF_EDGE_NORMAL;
 
        if ( is_round > 0 && is_round >= is_straight )
          edge->flags |= AF_EDGE_ROUND;
 
#if 0
        /* set the edge's main direction */
        edge->dir = AF_DIR_NONE;
 
        if ( ups > downs )
          edge->dir = (FT_Char)up_dir;
 
        else if ( ups < downs )
          edge->dir = (FT_Char)-up_dir;
 
        else if ( ups == downs )
          edge->dir = 0;  /* both up and down! */
#endif
 
        /* get rid of serifs if link is set                 */
        /* XXX: This gets rid of many unpleasant artefacts! */
        /*      Example: the `c' in cour.pfa at size 13     */
 
        if ( edge->serif && edge->link )
          edge->serif = NULL;
      }
    }
 
  Exit:
    return error;
  }

Referenced by af_latin_hints_detect_features().

af_latin_hints_compute_segments()

af_latin_hints_compute_segments	(	AF_GlyphHints	hints,
		AF_Dimension	dim
	)

Definition at line 1522 of file aflatin.c.

  {
    AF_LatinMetrics  metrics       = (AF_LatinMetrics)hints->metrics;
    AF_AxisHints     axis          = &hints->axis[dim];
    FT_Memory        memory        = hints->memory;
    FT_Error         error         = FT_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_Pos  flat_threshold = FLAT_THRESHOLD( metrics->units_per_em );
 
 
    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  last    = point->prev;
      int       on_edge = 0;
 
      /* we call values measured along a segment (point->v)    */
      /* `coordinates', and values orthogonal to it (point->u) */
      /* `positions'                                           */
      FT_Pos     min_pos      =  32000;
      FT_Pos     max_pos      = -32000;
      FT_Pos     min_coord    =  32000;
      FT_Pos     max_coord    = -32000;
      FT_UShort  min_flags    =  AF_FLAG_NONE;
      FT_UShort  max_flags    =  AF_FLAG_NONE;
      FT_Pos     min_on_coord =  32000;
      FT_Pos     max_on_coord = -32000;
 
      FT_Bool  passed;
 
      AF_Segment  prev_segment = NULL;
 
      FT_Pos     prev_min_pos      = min_pos;
      FT_Pos     prev_max_pos      = max_pos;
      FT_Pos     prev_min_coord    = min_coord;
      FT_Pos     prev_max_coord    = max_coord;
      FT_UShort  prev_min_flags    = min_flags;
      FT_UShort  prev_max_flags    = max_flags;
      FT_Pos     prev_min_on_coord = min_on_coord;
      FT_Pos     prev_max_on_coord = max_on_coord;
 
 
      if ( FT_ABS( last->out_dir )  == major_dir &&
           FT_ABS( point->out_dir ) == major_dir )
      {
        /* we are already on an edge, try to locate its start */
        last = point;
 
        for (;;)
        {
          point = point->prev;
          if ( FT_ABS( point->out_dir ) != major_dir )
          {
            point = point->next;
            break;
          }
          if ( point == last )
            break;
        }
      }
 
      last   = point;
      passed = 0;
 
      for (;;)
      {
        FT_Pos  u, v;
 
 
        if ( on_edge )
        {
          /* get minimum and maximum position */
          u = point->u;
          if ( u < min_pos )
            min_pos = u;
          if ( u > max_pos )
            max_pos = u;
 
          /* get minimum and maximum coordinate together with flags */
          v = point->v;
          if ( v < min_coord )
          {
            min_coord = v;
            min_flags = point->flags;
          }
          if ( v > max_coord )
          {
            max_coord = v;
            max_flags = point->flags;
          }
 
          /* get minimum and maximum coordinate of `on' points */
          if ( !( point->flags & AF_FLAG_CONTROL ) )
          {
            v = point->v;
            if ( v < min_on_coord )
              min_on_coord = v;
            if ( v > max_on_coord )
              max_on_coord = v;
          }
 
          if ( point->out_dir != segment_dir || point == last )
          {
            /* check whether the new segment's start point is identical to */
            /* the previous segment's end point; for example, this might   */
            /* happen for spikes                                           */
 
            if ( !prev_segment || segment->first != prev_segment->last )
            {
              /* points are different: we are just leaving an edge, thus */
              /* record a new segment                                    */
 
              segment->last  = point;
              segment->pos   = (FT_Short)( ( min_pos + max_pos ) >> 1 );
              segment->delta = (FT_Short)( ( max_pos - min_pos ) >> 1 );
 
              /* a segment is round if either its first or last point */
              /* is a control point, and the length of the on points  */
              /* inbetween doesn't exceed a heuristic limit           */
              if ( ( min_flags | max_flags ) & AF_FLAG_CONTROL      &&
                   ( max_on_coord - min_on_coord ) < flat_threshold )
                segment->flags |= AF_EDGE_ROUND;
 
              segment->min_coord = (FT_Short)min_coord;
              segment->max_coord = (FT_Short)max_coord;
              segment->height    = segment->max_coord - segment->min_coord;
 
              prev_segment      = segment;
              prev_min_pos      = min_pos;
              prev_max_pos      = max_pos;
              prev_min_coord    = min_coord;
              prev_max_coord    = max_coord;
              prev_min_flags    = min_flags;
              prev_max_flags    = max_flags;
              prev_min_on_coord = min_on_coord;
              prev_max_on_coord = max_on_coord;
            }
            else
            {
              /* points are the same: we don't create a new segment but */
              /* merge the current segment with the previous one        */
 
              if ( prev_segment->last->in_dir == point->in_dir )
              {
                /* we have identical directions (this can happen for       */
                /* degenerate outlines that move zig-zag along the main    */
                /* axis without changing the coordinate value of the other */
                /* axis, and where the segments have just been merged):    */
                /* unify segments                                          */
 
                /* update constraints */
 
                if ( prev_min_pos < min_pos )
                  min_pos = prev_min_pos;
                if ( prev_max_pos > max_pos )
                  max_pos = prev_max_pos;
 
                if ( prev_min_coord < min_coord )
                {
                  min_coord = prev_min_coord;
                  min_flags = prev_min_flags;
                }
                if ( prev_max_coord > max_coord )
                {
                  max_coord = prev_max_coord;
                  max_flags = prev_max_flags;
                }
 
                if ( prev_min_on_coord < min_on_coord )
                  min_on_coord = prev_min_on_coord;
                if ( prev_max_on_coord > max_on_coord )
                  max_on_coord = prev_max_on_coord;
 
                prev_segment->last  = point;
                prev_segment->pos   = (FT_Short)( ( min_pos +
                                                    max_pos ) >> 1 );
                prev_segment->delta = (FT_Short)( ( max_pos -
                                                    min_pos ) >> 1 );
 
                if ( ( min_flags | max_flags ) & AF_FLAG_CONTROL      &&
                     ( max_on_coord - min_on_coord ) < flat_threshold )
                  prev_segment->flags |= AF_EDGE_ROUND;
                else
                  prev_segment->flags &= ~AF_EDGE_ROUND;
 
                prev_segment->min_coord = (FT_Short)min_coord;
                prev_segment->max_coord = (FT_Short)max_coord;
                prev_segment->height    = prev_segment->max_coord -
                                          prev_segment->min_coord;
              }
              else
              {
                /* we have different directions; use the properties of the */
                /* longer segment and discard the other one                */
 
                if ( FT_ABS( prev_max_coord - prev_min_coord ) >
                     FT_ABS( max_coord - min_coord ) )
                {
                  /* discard current segment */
 
                  if ( min_pos < prev_min_pos )
                    prev_min_pos = min_pos;
                  if ( max_pos > prev_max_pos )
                    prev_max_pos = max_pos;
 
                  prev_segment->last  = point;
                  prev_segment->pos   = (FT_Short)( ( prev_min_pos +
                                                      prev_max_pos ) >> 1 );
                  prev_segment->delta = (FT_Short)( ( prev_max_pos -
                                                      prev_min_pos ) >> 1 );
                }
                else
                {
                  /* discard previous segment */
 
                  if ( prev_min_pos < min_pos )
                    min_pos = prev_min_pos;
                  if ( prev_max_pos > max_pos )
                    max_pos = prev_max_pos;
 
                  segment->last  = point;
                  segment->pos   = (FT_Short)( ( min_pos + max_pos ) >> 1 );
                  segment->delta = (FT_Short)( ( max_pos - min_pos ) >> 1 );
 
                  if ( ( min_flags | max_flags ) & AF_FLAG_CONTROL      &&
                       ( max_on_coord - min_on_coord ) < flat_threshold )
                    segment->flags |= AF_EDGE_ROUND;
 
                  segment->min_coord = (FT_Short)min_coord;
                  segment->max_coord = (FT_Short)max_coord;
                  segment->height    = segment->max_coord -
                                       segment->min_coord;
 
                  *prev_segment = *segment;
 
                  prev_min_pos      = min_pos;
                  prev_max_pos      = max_pos;
                  prev_min_coord    = min_coord;
                  prev_max_coord    = max_coord;
                  prev_min_flags    = min_flags;
                  prev_max_flags    = max_flags;
                  prev_min_on_coord = min_on_coord;
                  prev_max_on_coord = max_on_coord;
                }
              }
 
              axis->num_segments--;
            }
 
            on_edge = 0;
            segment = NULL;
 
            /* fall through */
          }
        }
 
        /* now exit if we are at the start/end point */
        if ( point == last )
        {
          if ( passed )
            break;
          passed = 1;
        }
 
        /* if we are not on an edge, check whether the major direction */
        /* coincides with the current point's `out' direction, or      */
        /* whether we have a single-point contour                      */
        if ( !on_edge                                  &&
             ( FT_ABS( point->out_dir ) == major_dir ||
               point == point->prev                  ) )
        {
          /* this is the start of a new segment! */
          segment_dir = (AF_Direction)point->out_dir;
 
          error = af_axis_hints_new_segment( axis, memory, &segment );
          if ( error )
            goto Exit;
 
          /* clear all segment fields */
          segment[0] = seg0;
 
          segment->dir   = (FT_Char)segment_dir;
          segment->first = point;
          segment->last  = point;
 
          /* `af_axis_hints_new_segment' reallocates memory,    */
          /* thus we have to refresh the `prev_segment' pointer */
          if ( prev_segment )
            prev_segment = segment - 1;
 
          min_pos   = max_pos   = point->u;
          min_coord = max_coord = point->v;
          min_flags = max_flags = point->flags;
 
          if ( point->flags & AF_FLAG_CONTROL )
          {
            min_on_coord =  32000;
            max_on_coord = -32000;
          }
          else
            min_on_coord = max_on_coord = point->v;
 
          on_edge = 1;
 
          if ( point == point->prev )
          {
            /* we have a one-point segment: this is a one-point */
            /* contour with `in' and `out' direction set to     */
            /* AF_DIR_NONE                                      */
            segment->pos = (FT_Short)min_pos;
 
            if (point->flags & AF_FLAG_CONTROL)
              segment->flags |= AF_EDGE_ROUND;
 
            segment->min_coord = (FT_Short)point->v;
            segment->max_coord = (FT_Short)point->v;
            segment->height = 0;
 
            on_edge = 0;
            segment = NULL;
          }
        }
 
        point = point->next;
      }
 
    } /* contours */
 
 
    /* now slightly increase the height of segments if 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;
        FT_Pos    first_v = first->v;
        FT_Pos    last_v  = last->v;
 
 
        if ( first_v < last_v )
        {
          AF_Point  p;
 
 
          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
        {
          AF_Point  p;
 
 
          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 ) );
        }
      }
    }
 
  Exit:
    return error;
  }

Referenced by af_latin_hints_detect_features(), and af_latin_metrics_init_widths().

af_latin_hints_detect_features()

af_latin_hints_detect_features	(	AF_GlyphHints	hints,
		FT_UInt	width_count,
		AF_WidthRec *	widths,
		AF_Dimension	dim
	)

Definition at line 2440 of file aflatin.c.

  {
    FT_Error  error;
 
 
    error = af_latin_hints_compute_segments( hints, dim );
    if ( !error )
    {
      af_latin_hints_link_segments( hints, width_count, widths, dim );
 
      error = af_latin_hints_compute_edges( hints, dim );
    }
 
    return error;
  }

Referenced by af_latin_hints_apply().

af_latin_hints_link_segments()

af_latin_hints_link_segments	(	AF_GlyphHints	hints,
		FT_UInt	width_count,
		AF_WidthRec *	widths,
		AF_Dimension	dim
	)

Definition at line 1950 of file aflatin.c.

  {
    AF_AxisHints  axis          = &hints->axis[dim];
    AF_Segment    segments      = axis->segments;
    AF_Segment    segment_limit = segments + axis->num_segments;
    FT_Pos        len_threshold, len_score, dist_score, max_width;
    AF_Segment    seg1, seg2;
 
 
    if ( width_count )
      max_width = widths[width_count - 1].org;
    else
      max_width = 0;
 
    /* a heuristic value to set up a minimum value for overlapping */
    len_threshold = AF_LATIN_CONSTANT( hints->metrics, 8 );
    if ( len_threshold == 0 )
      len_threshold = 1;
 
    /* a heuristic value to weight lengths */
    len_score = AF_LATIN_CONSTANT( hints->metrics, 6000 );
 
    /* a heuristic value to weight distances (no call to    */
    /* AF_LATIN_CONSTANT needed, since we work on multiples */
    /* of the stem width)                                   */
    dist_score = 3000;
 
    /* now compare each segment to the others */
    for ( seg1 = segments; seg1 < segment_limit; seg1++ )
    {
      if ( seg1->dir != axis->major_dir )
        continue;
 
      /* search for stems having opposite directions, */
      /* with seg1 to the `left' of seg2              */
      for ( seg2 = segments; seg2 < segment_limit; seg2++ )
      {
        FT_Pos  pos1 = seg1->pos;
        FT_Pos  pos2 = seg2->pos;
 
 
        if ( seg1->dir + seg2->dir == 0 && pos2 > pos1 )
        {
          /* compute distance between the two segments */
          FT_Pos  min = seg1->min_coord;
          FT_Pos  max = seg1->max_coord;
          FT_Pos  len;
 
 
          if ( min < seg2->min_coord )
            min = seg2->min_coord;
 
          if ( max > seg2->max_coord )
            max = seg2->max_coord;
 
          /* compute maximum coordinate difference of the two segments */
          /* (this is, how much they overlap)                          */
          len = max - min;
          if ( len >= len_threshold )
          {
            /*
             * The score is the sum of two demerits indicating the
             * `badness' of a fit, measured along the segments' main axis
             * and orthogonal to it, respectively.
             *
             * - The less overlapping along the main axis, the worse it
             *   is, causing a larger demerit.
             *
             * - The nearer the orthogonal distance to a stem width, the
             *   better it is, causing a smaller demerit.  For simplicity,
             *   however, we only increase the demerit for values that
             *   exceed the largest stem width.
             */
 
            FT_Pos  dist = pos2 - pos1;
 
            FT_Pos  dist_demerit, score;
 
 
            if ( max_width )
            {
              /* distance demerits are based on multiples of `max_width'; */
              /* we scale by 1024 for getting more precision              */
              FT_Pos  delta = ( dist << 10 ) / max_width - ( 1 << 10 );
 
 
              if ( delta > 10000 )
                dist_demerit = 32000;
              else if ( delta > 0 )
                dist_demerit = delta * delta / dist_score;
              else
                dist_demerit = 0;
            }
            else
              dist_demerit = dist; /* default if no widths available */
 
            score = dist_demerit + len_score / len;
 
            /* and we search for the smallest score */
            if ( score < seg1->score )
            {
              seg1->score = score;
              seg1->link  = seg2;
            }
 
            if ( score < seg2->score )
            {
              seg2->score = score;
              seg2->link  = seg1;
            }
          }
        }
      }
    }
 
    /* now compute the `serif' segments, cf. explanations in `afhints.h' */
    for ( seg1 = segments; seg1 < segment_limit; seg1++ )
    {
      seg2 = seg1->link;
 
      if ( seg2 )
      {
        if ( seg2->link != seg1 )
        {
          seg1->link  = 0;
          seg1->serif = seg2->link;
        }
      }
    }
  }

Referenced by af_latin_hints_detect_features(), and af_latin_metrics_init_widths().

af_latin_metrics_check_digits()

af_latin_metrics_check_digits	(	AF_LatinMetrics	metrics,
		FT_Face	face
	)

Definition at line 1067 of file aflatin.c.

  {
    FT_Bool   started = 0, same_width = 1;
    FT_Fixed  advance = 0, old_advance = 0;
 
    /* If HarfBuzz is not available, we need a pointer to a single */
    /* unsigned long value.                                        */
#ifdef FT_CONFIG_OPTION_USE_HARFBUZZ
    void*     shaper_buf;
#else
    FT_ULong  shaper_buf_;
    void*     shaper_buf = &shaper_buf_;
#endif
 
    /* in all supported charmaps, digits have character codes 0x30-0x39 */
    const char   digits[] = "0 1 2 3 4 5 6 7 8 9";
    const char*  p;
 
 
    p = digits;
 
#ifdef FT_CONFIG_OPTION_USE_HARFBUZZ
    shaper_buf = af_shaper_buf_create( face );
#endif
 
    while ( *p )
    {
      FT_ULong      glyph_index;
      unsigned int  num_idx;
 
 
      /* reject input that maps to more than a single glyph */
      p = af_shaper_get_cluster( p, &metrics->root, shaper_buf, &num_idx );
      if ( num_idx > 1 )
        continue;
 
      glyph_index = af_shaper_get_elem( &metrics->root,
                                        shaper_buf,
                                        0,
                                        &advance,
                                        NULL );
      if ( !glyph_index )
        continue;
 
      if ( started )
      {
        if ( advance != old_advance )
        {
          same_width = 0;
          break;
        }
      }
      else
      {
        old_advance = advance;
        started     = 1;
      }
    }
 
    af_shaper_buf_destroy( face, shaper_buf );
 
    metrics->root.digits_have_same_width = same_width;
  }

Referenced by af_latin_metrics_init().

af_latin_metrics_init()

af_latin_metrics_init	(	AF_LatinMetrics	metrics,
		FT_Face	face
	)

Definition at line 1136 of file aflatin.c.

  {
    FT_CharMap  oldmap = face->charmap;
 
 
    metrics->units_per_em = face->units_per_EM;
 
    if ( !FT_Select_Charmap( face, FT_ENCODING_UNICODE ) )
    {
      af_latin_metrics_init_widths( metrics, face );
      af_latin_metrics_init_blues( metrics, face );
      af_latin_metrics_check_digits( metrics, face );
    }
 
    FT_Set_Charmap( face, oldmap );
    return FT_Err_Ok;
  }

af_latin_metrics_init_widths()

af_latin_metrics_init_widths	(	AF_LatinMetrics	metrics,
		FT_Face	face
	)

Definition at line 60 of file aflatin.c.

  {
    /* scan the array of segments in each direction */
#ifdef __REACTOS__
    AF_GlyphHintsRec *hints = malloc(sizeof(*hints));
    if (!hints) return;
#else
    AF_GlyphHintsRec  hints[1];
#endif
 
 
    FT_TRACE5(( "\n"
                "latin standard widths computation (style `%s')\n"
                "=====================================================\n"
                "\n",
                af_style_names[metrics->root.style_class->style] ));
 
    af_glyph_hints_init( hints, face->memory );
 
    metrics->axis[AF_DIMENSION_HORZ].width_count = 0;
    metrics->axis[AF_DIMENSION_VERT].width_count = 0;
 
    {
      FT_Error            error;
      FT_ULong            glyph_index;
      int                 dim;
#ifdef __REACTOS__
      AF_LatinMetricsRec *dummy = malloc(sizeof(*dummy));
      if (!dummy)
        goto Exit;
      {
#else
      AF_LatinMetricsRec  dummy[1];
#endif
      AF_Scaler           scaler = &dummy->root.scaler;
 
      AF_StyleClass   style_class  = metrics->root.style_class;
      AF_ScriptClass  script_class = af_script_classes[style_class->script];
 
      /* If HarfBuzz is not available, we need a pointer to a single */
      /* unsigned long value.                                        */
#ifdef FT_CONFIG_OPTION_USE_HARFBUZZ
      void*     shaper_buf;
#else
      FT_ULong  shaper_buf_;
      void*     shaper_buf = &shaper_buf_;
#endif
 
      const char*  p;
 
#ifdef FT_DEBUG_LEVEL_TRACE
      FT_ULong  ch = 0;
#endif
 
 
      p = script_class->standard_charstring;
 
#ifdef FT_CONFIG_OPTION_USE_HARFBUZZ
      shaper_buf = af_shaper_buf_create( face );
#endif
      /*
       * We check a list of standard characters to catch features like
       * `c2sc' (small caps from caps) that don't contain lowercase letters
       * by definition, or other features that mainly operate on numerals.
       * The first match wins.
       */
 
      glyph_index = 0;
      while ( *p )
      {
        unsigned int  num_idx;
 
#ifdef FT_DEBUG_LEVEL_TRACE
        const char*  p_old;
#endif
 
 
        while ( *p == ' ' )
          p++;
 
#ifdef FT_DEBUG_LEVEL_TRACE
        p_old = p;
        GET_UTF8_CHAR( ch, p_old );
#endif
 
        /* reject input that maps to more than a single glyph */
        p = af_shaper_get_cluster( p, &metrics->root, shaper_buf, &num_idx );
        if ( num_idx > 1 )
          continue;
 
        /* otherwise exit loop if we have a result */
        glyph_index = af_shaper_get_elem( &metrics->root,
                                          shaper_buf,
                                          0,
                                          NULL,
                                          NULL );
        if ( glyph_index )
          break;
      }
 
      af_shaper_buf_destroy( face, shaper_buf );
 
      if ( !glyph_index )
        goto Exit;
 
      FT_TRACE5(( "standard character: U+%04lX (glyph index %d)\n",
                  ch, glyph_index ));
 
      error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE );
      if ( error || face->glyph->outline.n_points <= 0 )
        goto Exit;
 
      FT_ZERO( dummy );
 
      dummy->units_per_em = metrics->units_per_em;
 
      scaler->x_scale = 0x10000L;
      scaler->y_scale = 0x10000L;
      scaler->x_delta = 0;
      scaler->y_delta = 0;
 
      scaler->face        = face;
      scaler->render_mode = FT_RENDER_MODE_NORMAL;
      scaler->flags       = 0;
 
      af_glyph_hints_rescale( hints, (AF_StyleMetrics)dummy );
 
      error = af_glyph_hints_reload( hints, &face->glyph->outline );
      if ( error )
        goto Exit;
 
      for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
      {
        AF_LatinAxis  axis    = &metrics->axis[dim];
        AF_AxisHints  axhints = &hints->axis[dim];
        AF_Segment    seg, limit, link;
        FT_UInt       num_widths = 0;
 
 
        error = af_latin_hints_compute_segments( hints,
                                                 (AF_Dimension)dim );
        if ( error )
          goto Exit;
 
        /*
         * We assume that the glyphs selected for the stem width
         * computation are `featureless' enough so that the linking
         * algorithm works fine without adjustments of its scoring
         * function.
         */
        af_latin_hints_link_segments( hints,
                                      0,
                                      NULL,
                                      (AF_Dimension)dim );
 
        seg   = axhints->segments;
        limit = seg + axhints->num_segments;
 
        for ( ; seg < limit; seg++ )
        {
          link = seg->link;
 
          /* we only consider stem segments there! */
          if ( link && link->link == seg && link > seg )
          {
            FT_Pos  dist;
 
 
            dist = seg->pos - link->pos;
            if ( dist < 0 )
              dist = -dist;
 
            if ( num_widths < AF_LATIN_MAX_WIDTHS )
              axis->widths[num_widths++].org = dist;
          }
        }
 
        /* this also replaces multiple almost identical stem widths */
        /* with a single one (the value 100 is heuristic)           */
        af_sort_and_quantize_widths( &num_widths, axis->widths,
                                     dummy->units_per_em / 100 );
        axis->width_count = num_widths;
      }
 
    Exit:
      for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
      {
        AF_LatinAxis  axis = &metrics->axis[dim];
        FT_Pos        stdw;
 
 
        stdw = ( axis->width_count > 0 ) ? axis->widths[0].org
                                         : AF_LATIN_CONSTANT( metrics, 50 );
 
        /* let's try 20% of the smallest width */
        axis->edge_distance_threshold = stdw / 5;
        axis->standard_width          = stdw;
        axis->extra_light             = 0;
 
#ifdef FT_DEBUG_LEVEL_TRACE
        {
          FT_UInt  i;
 
 
          FT_TRACE5(( "%s widths:\n",
                      dim == AF_DIMENSION_VERT ? "horizontal"
                                               : "vertical" ));
 
          FT_TRACE5(( "  %d (standard)", axis->standard_width ));
          for ( i = 1; i < axis->width_count; i++ )
            FT_TRACE5(( " %d", axis->widths[i].org ));
 
          FT_TRACE5(( "\n" ));
        }
#endif
      }
#ifdef __REACTOS__
      free(dummy);
      }
#endif
    }
 
    FT_TRACE5(( "\n" ));
 
    af_glyph_hints_done( hints );
 
#ifdef __REACTOS__
    free(hints);
#endif
  }

Referenced by af_latin_metrics_init().

af_latin_metrics_scale()

af_latin_metrics_scale	(	AF_LatinMetrics	metrics,
		AF_Scaler	scaler
	)

Definition at line 1482 of file aflatin.c.

  {
    metrics->root.scaler.render_mode = scaler->render_mode;
    metrics->root.scaler.face        = scaler->face;
    metrics->root.scaler.flags       = scaler->flags;
 
    af_latin_metrics_scale_dim( metrics, scaler, AF_DIMENSION_HORZ );
    af_latin_metrics_scale_dim( metrics, scaler, AF_DIMENSION_VERT );
  }