1 /***************************************************************************/
5 /* Auto-fitter hinting routines (body). */
7 /* Copyright 2003-2016 by */
8 /* David Turner, Robert Wilhelm, and Werner Lemberg. */
10 /* This file is part of the FreeType project, and may only be used, */
11 /* modified, and distributed under the terms of the FreeType project */
12 /* license, LICENSE.TXT. By continuing to use, modify, or distribute */
13 /* this file you indicate that you have read the license and */
14 /* understand and accept it fully. */
16 /***************************************************************************/
21 #include FT_INTERNAL_CALC_H
22 #include FT_INTERNAL_DEBUG_H
25 /*************************************************************************/
27 /* The macro FT_COMPONENT is used in trace mode. It is an implicit */
28 /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */
29 /* messages during execution. */
32 #define FT_COMPONENT trace_afhints
35 /* Get new segment for given axis. */
37 FT_LOCAL_DEF( FT_Error )
38 af_axis_hints_new_segment( AF_AxisHints axis,
40 AF_Segment *asegment )
42 FT_Error error = FT_Err_Ok;
43 AF_Segment segment = NULL;
46 if ( axis->num_segments < AF_SEGMENTS_EMBEDDED )
48 if ( axis->segments == NULL )
50 axis->segments = axis->embedded.segments;
51 axis->max_segments = AF_SEGMENTS_EMBEDDED;
54 else if ( axis->num_segments >= axis->max_segments )
56 FT_Int old_max = axis->max_segments;
57 FT_Int new_max = old_max;
58 FT_Int big_max = (FT_Int)( FT_INT_MAX / sizeof ( *segment ) );
61 if ( old_max >= big_max )
63 error = FT_THROW( Out_Of_Memory );
67 new_max += ( new_max >> 2 ) + 4;
68 if ( new_max < old_max || new_max > big_max )
71 if ( axis->segments == axis->embedded.segments )
73 if ( FT_NEW_ARRAY( axis->segments, new_max ) )
75 ft_memcpy( axis->segments, axis->embedded.segments,
76 sizeof ( axis->embedded.segments ) );
80 if ( FT_RENEW_ARRAY( axis->segments, old_max, new_max ) )
84 axis->max_segments = new_max;
87 segment = axis->segments + axis->num_segments++;
95 /* Get new edge for given axis, direction, and position, */
96 /* without initializing the edge itself. */
99 af_axis_hints_new_edge( AF_AxisHints axis,
102 FT_Bool top_to_bottom_hinting,
106 FT_Error error = FT_Err_Ok;
111 if ( axis->num_edges < AF_EDGES_EMBEDDED )
113 if ( axis->edges == NULL )
115 axis->edges = axis->embedded.edges;
116 axis->max_edges = AF_EDGES_EMBEDDED;
119 else if ( axis->num_edges >= axis->max_edges )
121 FT_Int old_max = axis->max_edges;
122 FT_Int new_max = old_max;
123 FT_Int big_max = (FT_Int)( FT_INT_MAX / sizeof ( *edge ) );
126 if ( old_max >= big_max )
128 error = FT_THROW( Out_Of_Memory );
132 new_max += ( new_max >> 2 ) + 4;
133 if ( new_max < old_max || new_max > big_max )
136 if ( axis->edges == axis->embedded.edges )
138 if ( FT_NEW_ARRAY( axis->edges, new_max ) )
140 ft_memcpy( axis->edges, axis->embedded.edges,
141 sizeof ( axis->embedded.edges ) );
145 if ( FT_RENEW_ARRAY( axis->edges, old_max, new_max ) )
149 axis->max_edges = new_max;
153 edge = edges + axis->num_edges;
155 while ( edge > edges )
157 if ( top_to_bottom_hinting ? ( edge[-1].fpos > fpos )
158 : ( edge[-1].fpos < fpos ) )
161 /* we want the edge with same position and minor direction */
162 /* to appear before those in the major one in the list */
163 if ( edge[-1].fpos == fpos && dir == axis->major_dir )
178 #ifdef FT_DEBUG_AUTOFIT
180 #include FT_CONFIG_STANDARD_LIBRARY_H
182 /* The dump functions are used in the `ftgrid' demo program, too. */
183 #define AF_DUMP( varformat ) \
189 FT_TRACE7( varformat ); \
194 af_dir_str( AF_Direction dir )
221 #define AF_INDEX_NUM( ptr, base ) (int)( (ptr) ? ( (ptr) - (base) ) : -1 )
225 af_print_idx( char* p,
235 ft_sprintf( p, "%d", idx );
242 af_get_segment_index( AF_GlyphHints hints,
246 AF_AxisHints axis = &hints->axis[dimension];
247 AF_Point point = hints->points + point_idx;
248 AF_Segment segments = axis->segments;
249 AF_Segment limit = segments + axis->num_segments;
253 for ( segment = segments; segment < limit; segment++ )
255 if ( segment->first <= segment->last )
257 if ( point >= segment->first && point <= segment->last )
262 AF_Point p = segment->first;
270 if ( p == segment->last )
279 if ( segment == limit )
282 return (int)( segment - segments );
287 af_get_edge_index( AF_GlyphHints hints,
291 AF_AxisHints axis = &hints->axis[dimension];
292 AF_Edge edges = axis->edges;
293 AF_Segment segment = axis->segments + segment_idx;
296 return segment_idx == -1 ? -1 : AF_INDEX_NUM( segment->edge, edges );
304 af_glyph_hints_dump_points( AF_GlyphHints hints,
307 AF_Point points = hints->points;
308 AF_Point limit = points + hints->num_points;
309 AF_Point* contour = hints->contours;
310 AF_Point* climit = contour + hints->num_contours;
314 AF_DUMP(( "Table of points:\n" ));
316 if ( hints->num_points )
317 AF_DUMP(( " index hedge hseg vedge vseg flags "
318 " xorg yorg xscale yscale xfit yfit" ));
320 AF_DUMP(( " (none)\n" ));
322 for ( point = points; point < limit; point++ )
324 int point_idx = AF_INDEX_NUM( point, points );
325 int segment_idx_0 = af_get_segment_index( hints, point_idx, 0 );
326 int segment_idx_1 = af_get_segment_index( hints, point_idx, 1 );
328 char buf1[16], buf2[16], buf3[16], buf4[16];
331 /* insert extra newline at the beginning of a contour */
332 if ( contour < climit && *contour == point )
338 AF_DUMP(( " %5d %5s %5s %5s %5s %s"
339 " %5d %5d %7.2f %7.2f %7.2f %7.2f\n",
342 af_get_edge_index( hints, segment_idx_1, 1 ) ),
343 af_print_idx( buf2, segment_idx_1 ),
345 af_get_edge_index( hints, segment_idx_0, 0 ) ),
346 af_print_idx( buf4, segment_idx_0 ),
347 ( point->flags & AF_FLAG_NEAR )
349 : ( point->flags & AF_FLAG_WEAK_INTERPOLATION )
368 af_edge_flags_to_string( FT_UInt flags )
370 static char temp[32];
374 if ( flags & AF_EDGE_ROUND )
376 ft_memcpy( temp + pos, "round", 5 );
379 if ( flags & AF_EDGE_SERIF )
383 ft_memcpy( temp + pos, "serif", 5 );
395 /* Dump the array of linked segments. */
401 af_glyph_hints_dump_segments( AF_GlyphHints hints,
407 for ( dimension = 1; dimension >= 0; dimension-- )
409 AF_AxisHints axis = &hints->axis[dimension];
410 AF_Point points = hints->points;
411 AF_Edge edges = axis->edges;
412 AF_Segment segments = axis->segments;
413 AF_Segment limit = segments + axis->num_segments;
416 char buf1[16], buf2[16], buf3[16];
419 AF_DUMP(( "Table of %s segments:\n",
420 dimension == AF_DIMENSION_HORZ ? "vertical"
422 if ( axis->num_segments )
423 AF_DUMP(( " index pos dir from to"
425 " height extra flags\n" ));
427 AF_DUMP(( " (none)\n" ));
429 for ( seg = segments; seg < limit; seg++ )
430 AF_DUMP(( " %5d %5.2g %5s %4d %4d"
433 AF_INDEX_NUM( seg, segments ),
434 dimension == AF_DIMENSION_HORZ
435 ? (int)seg->first->ox / 64.0
436 : (int)seg->first->oy / 64.0,
437 af_dir_str( (AF_Direction)seg->dir ),
438 AF_INDEX_NUM( seg->first, points ),
439 AF_INDEX_NUM( seg->last, points ),
441 af_print_idx( buf1, AF_INDEX_NUM( seg->link, segments ) ),
442 af_print_idx( buf2, AF_INDEX_NUM( seg->serif, segments ) ),
443 af_print_idx( buf3, AF_INDEX_NUM( seg->edge, edges ) ),
446 seg->height - ( seg->max_coord - seg->min_coord ),
447 af_edge_flags_to_string( seg->flags ) ));
456 /* Fetch number of segments. */
462 af_glyph_hints_get_num_segments( AF_GlyphHints hints,
464 FT_Int* num_segments )
470 dim = ( dimension == 0 ) ? AF_DIMENSION_HORZ : AF_DIMENSION_VERT;
472 axis = &hints->axis[dim];
473 *num_segments = axis->num_segments;
482 /* Fetch offset of segments into user supplied offset array. */
488 af_glyph_hints_get_segment_offset( AF_GlyphHints hints,
493 FT_Pos *blue_offset )
501 return FT_THROW( Invalid_Argument );
503 dim = ( dimension == 0 ) ? AF_DIMENSION_HORZ : AF_DIMENSION_VERT;
505 axis = &hints->axis[dim];
507 if ( idx < 0 || idx >= axis->num_segments )
508 return FT_THROW( Invalid_Argument );
510 seg = &axis->segments[idx];
511 *offset = ( dim == AF_DIMENSION_HORZ ) ? seg->first->ox
514 *is_blue = (FT_Bool)( seg->edge->blue_edge != 0 );
519 *blue_offset = seg->edge->blue_edge->cur;
530 /* Dump the array of linked edges. */
536 af_glyph_hints_dump_edges( AF_GlyphHints hints,
542 for ( dimension = 1; dimension >= 0; dimension-- )
544 AF_AxisHints axis = &hints->axis[dimension];
545 AF_Edge edges = axis->edges;
546 AF_Edge limit = edges + axis->num_edges;
549 char buf1[16], buf2[16];
553 * note: AF_DIMENSION_HORZ corresponds to _vertical_ edges
554 * since they have a constant X coordinate.
556 AF_DUMP(( "Table of %s edges:\n",
557 dimension == AF_DIMENSION_HORZ ? "vertical"
559 if ( axis->num_edges )
560 AF_DUMP(( " index pos dir link serif"
561 " blue opos pos flags\n" ));
563 AF_DUMP(( " (none)\n" ));
565 for ( edge = edges; edge < limit; edge++ )
566 AF_DUMP(( " %5d %5.2g %5s %4s %5s"
567 " %c %5.2f %5.2f %11s\n",
568 AF_INDEX_NUM( edge, edges ),
569 (int)edge->opos / 64.0,
570 af_dir_str( (AF_Direction)edge->dir ),
571 af_print_idx( buf1, AF_INDEX_NUM( edge->link, edges ) ),
572 af_print_idx( buf2, AF_INDEX_NUM( edge->serif, edges ) ),
574 edge->blue_edge ? 'y' : 'n',
577 af_edge_flags_to_string( edge->flags ) ));
587 #endif /* !FT_DEBUG_AUTOFIT */
590 /* Compute the direction value of a given vector. */
592 FT_LOCAL_DEF( AF_Direction )
593 af_direction_compute( FT_Pos dx,
596 FT_Pos ll, ss; /* long and short arm lengths */
597 AF_Direction dir; /* candidate direction */
631 /* return no direction if arm lengths do not differ enough */
632 /* (value 14 is heuristic, corresponding to approx. 4.1 degrees) */
633 /* the long arm is never negative */
634 if ( ll <= 14 * FT_ABS( ss ) )
642 af_glyph_hints_init( AF_GlyphHints hints,
645 /* no need to initialize the embedded items */
646 FT_MEM_ZERO( hints, sizeof ( *hints ) - sizeof ( hints->embedded ) );
647 hints->memory = memory;
652 af_glyph_hints_done( AF_GlyphHints hints )
658 if ( !( hints && hints->memory ) )
661 memory = hints->memory;
664 * note that we don't need to free the segment and edge
665 * buffers since they are really within the hints->points array
667 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
669 AF_AxisHints axis = &hints->axis[dim];
672 axis->num_segments = 0;
673 axis->max_segments = 0;
674 if ( axis->segments != axis->embedded.segments )
675 FT_FREE( axis->segments );
679 if ( axis->edges != axis->embedded.edges )
680 FT_FREE( axis->edges );
683 if ( hints->contours != hints->embedded.contours )
684 FT_FREE( hints->contours );
685 hints->max_contours = 0;
686 hints->num_contours = 0;
688 if ( hints->points != hints->embedded.points )
689 FT_FREE( hints->points );
690 hints->max_points = 0;
691 hints->num_points = 0;
693 hints->memory = NULL;
700 af_glyph_hints_rescale( AF_GlyphHints hints,
701 AF_StyleMetrics metrics )
703 hints->metrics = metrics;
704 hints->scaler_flags = metrics->scaler.flags;
708 /* Recompute all AF_Point in AF_GlyphHints from the definitions */
709 /* in a source outline. */
711 FT_LOCAL_DEF( FT_Error )
712 af_glyph_hints_reload( AF_GlyphHints hints,
713 FT_Outline* outline )
715 FT_Error error = FT_Err_Ok;
717 FT_UInt old_max, new_max;
718 FT_Fixed x_scale = hints->x_scale;
719 FT_Fixed y_scale = hints->y_scale;
720 FT_Pos x_delta = hints->x_delta;
721 FT_Pos y_delta = hints->y_delta;
722 FT_Memory memory = hints->memory;
725 hints->num_points = 0;
726 hints->num_contours = 0;
728 hints->axis[0].num_segments = 0;
729 hints->axis[0].num_edges = 0;
730 hints->axis[1].num_segments = 0;
731 hints->axis[1].num_edges = 0;
733 /* first of all, reallocate the contours array if necessary */
734 new_max = (FT_UInt)outline->n_contours;
735 old_max = (FT_UInt)hints->max_contours;
737 if ( new_max <= AF_CONTOURS_EMBEDDED )
739 if ( hints->contours == NULL )
741 hints->contours = hints->embedded.contours;
742 hints->max_contours = AF_CONTOURS_EMBEDDED;
745 else if ( new_max > old_max )
747 if ( hints->contours == hints->embedded.contours )
748 hints->contours = NULL;
750 new_max = ( new_max + 3 ) & ~3U; /* round up to a multiple of 4 */
752 if ( FT_RENEW_ARRAY( hints->contours, old_max, new_max ) )
755 hints->max_contours = (FT_Int)new_max;
759 * then reallocate the points arrays if necessary --
760 * note that we reserve two additional point positions, used to
761 * hint metrics appropriately
763 new_max = (FT_UInt)( outline->n_points + 2 );
764 old_max = (FT_UInt)hints->max_points;
766 if ( new_max <= AF_POINTS_EMBEDDED )
768 if ( hints->points == NULL )
770 hints->points = hints->embedded.points;
771 hints->max_points = AF_POINTS_EMBEDDED;
774 else if ( new_max > old_max )
776 if ( hints->points == hints->embedded.points )
777 hints->points = NULL;
779 new_max = ( new_max + 2 + 7 ) & ~7U; /* round up to a multiple of 8 */
781 if ( FT_RENEW_ARRAY( hints->points, old_max, new_max ) )
784 hints->max_points = (FT_Int)new_max;
787 hints->num_points = outline->n_points;
788 hints->num_contours = outline->n_contours;
790 /* We can't rely on the value of `FT_Outline.flags' to know the fill */
791 /* direction used for a glyph, given that some fonts are broken (e.g., */
792 /* the Arphic ones). We thus recompute it each time we need to. */
794 hints->axis[AF_DIMENSION_HORZ].major_dir = AF_DIR_UP;
795 hints->axis[AF_DIMENSION_VERT].major_dir = AF_DIR_LEFT;
797 if ( FT_Outline_Get_Orientation( outline ) == FT_ORIENTATION_POSTSCRIPT )
799 hints->axis[AF_DIMENSION_HORZ].major_dir = AF_DIR_DOWN;
800 hints->axis[AF_DIMENSION_VERT].major_dir = AF_DIR_RIGHT;
803 hints->x_scale = x_scale;
804 hints->y_scale = y_scale;
805 hints->x_delta = x_delta;
806 hints->y_delta = y_delta;
808 hints->xmin_delta = 0;
809 hints->xmax_delta = 0;
811 points = hints->points;
812 if ( hints->num_points == 0 )
817 AF_Point point_limit = points + hints->num_points;
819 /* value 20 in `near_limit' is heuristic */
820 FT_UInt units_per_em = hints->metrics->scaler.face->units_per_EM;
821 FT_Int near_limit = 20 * units_per_em / 2048;
824 /* compute coordinates & Bezier flags, next and prev */
826 FT_Vector* vec = outline->points;
827 char* tag = outline->tags;
828 FT_Short endpoint = outline->contours[0];
829 AF_Point end = points + endpoint;
831 FT_Int contour_index = 0;
834 for ( point = points; point < point_limit; point++, vec++, tag++ )
839 point->in_dir = (FT_Char)AF_DIR_NONE;
840 point->out_dir = (FT_Char)AF_DIR_NONE;
842 point->fx = (FT_Short)vec->x;
843 point->fy = (FT_Short)vec->y;
844 point->ox = point->x = FT_MulFix( vec->x, x_scale ) + x_delta;
845 point->oy = point->y = FT_MulFix( vec->y, y_scale ) + y_delta;
847 end->fx = (FT_Short)outline->points[endpoint].x;
848 end->fy = (FT_Short)outline->points[endpoint].y;
850 switch ( FT_CURVE_TAG( *tag ) )
852 case FT_CURVE_TAG_CONIC:
853 point->flags = AF_FLAG_CONIC;
855 case FT_CURVE_TAG_CUBIC:
856 point->flags = AF_FLAG_CUBIC;
859 point->flags = AF_FLAG_NONE;
862 out_x = point->fx - prev->fx;
863 out_y = point->fy - prev->fy;
865 if ( FT_ABS( out_x ) + FT_ABS( out_y ) < near_limit )
866 prev->flags |= AF_FLAG_NEAR;
874 if ( ++contour_index < outline->n_contours )
876 endpoint = outline->contours[contour_index];
877 end = points + endpoint;
884 /* set up the contours array */
886 AF_Point* contour = hints->contours;
887 AF_Point* contour_limit = contour + hints->num_contours;
888 short* end = outline->contours;
892 for ( ; contour < contour_limit; contour++, end++ )
894 contour[0] = points + idx;
895 idx = (short)( end[0] + 1 );
901 * Compute directions of `in' and `out' vectors.
903 * Note that distances between points that are very near to each
904 * other are accumulated. In other words, the auto-hinter either
905 * prepends the small vectors between near points to the first
906 * non-near vector, or the sum of small vector lengths exceeds a
907 * threshold, thus `grouping' the small vectors. All intermediate
908 * points are tagged as weak; the directions are adjusted also to
909 * be equal to the accumulated one.
912 FT_Int near_limit2 = 2 * near_limit - 1;
915 AF_Point* contour_limit = hints->contours + hints->num_contours;
918 for ( contour = hints->contours; contour < contour_limit; contour++ )
920 AF_Point first = *contour;
921 AF_Point next, prev, curr;
926 /* since the first point of a contour could be part of a */
927 /* series of near points, go backwards to find the first */
928 /* non-near point and adjust `first' */
933 while ( prev != first )
935 out_x = point->fx - prev->fx;
936 out_y = point->fy - prev->fy;
939 * We use Taxicab metrics to measure the vector length.
941 * Note that the accumulated distances so far could have the
942 * opposite direction of the distance measured here. For this
943 * reason we use `near_limit2' for the comparison to get a
944 * non-near point even in the worst case.
946 if ( FT_ABS( out_x ) + FT_ABS( out_y ) >= near_limit2 )
953 /* adjust first point */
956 /* now loop over all points of the contour to get */
957 /* `in' and `out' vector directions */
962 * We abuse the `u' and `v' fields to store index deltas to the
963 * next and previous non-near point, respectively.
965 * To avoid problems with not having non-near points, we point to
966 * `first' by default as the next non-near point.
969 curr->u = (FT_Pos)( first - curr );
978 AF_Direction out_dir;
984 out_x += next->fx - point->fx;
985 out_y += next->fy - point->fy;
987 if ( FT_ABS( out_x ) + FT_ABS( out_y ) < near_limit )
989 next->flags |= AF_FLAG_WEAK_INTERPOLATION;
993 curr->u = (FT_Pos)( next - curr );
996 out_dir = af_direction_compute( out_x, out_y );
998 /* adjust directions for all points inbetween; */
999 /* the loop also updates position of `curr' */
1000 curr->out_dir = (FT_Char)out_dir;
1001 for ( curr = curr->next; curr != next; curr = curr->next )
1003 curr->in_dir = (FT_Char)out_dir;
1004 curr->out_dir = (FT_Char)out_dir;
1006 next->in_dir = (FT_Char)out_dir;
1008 curr->u = (FT_Pos)( first - curr );
1009 first->v = -curr->u;
1014 } while ( next != first );
1018 * The next step is to `simplify' an outline's topology so that we
1019 * can identify local extrema more reliably: A series of
1020 * non-horizontal or non-vertical vectors pointing into the same
1021 * quadrant are handled as a single, long vector. From a
1022 * topological point of the view, the intermediate points are of no
1023 * interest and thus tagged as weak.
1026 for ( point = points; point < point_limit; point++ )
1028 if ( point->flags & AF_FLAG_WEAK_INTERPOLATION )
1031 if ( point->in_dir == AF_DIR_NONE &&
1032 point->out_dir == AF_DIR_NONE )
1034 /* check whether both vectors point into the same quadrant */
1037 FT_Pos out_x, out_y;
1039 AF_Point next_u = point + point->u;
1040 AF_Point prev_v = point + point->v;
1043 in_x = point->fx - prev_v->fx;
1044 in_y = point->fy - prev_v->fy;
1046 out_x = next_u->fx - point->fx;
1047 out_y = next_u->fy - point->fy;
1049 if ( ( in_x ^ out_x ) >= 0 && ( in_y ^ out_y ) >= 0 )
1051 /* yes, so tag current point as weak */
1052 /* and update index deltas */
1054 point->flags |= AF_FLAG_WEAK_INTERPOLATION;
1056 prev_v->u = (FT_Pos)( next_u - prev_v );
1057 next_u->v = -prev_v->u;
1063 * Finally, check for remaining weak points. Everything else not
1064 * collected in edges so far is then implicitly classified as strong
1068 for ( point = points; point < point_limit; point++ )
1070 if ( point->flags & AF_FLAG_WEAK_INTERPOLATION )
1073 if ( point->flags & AF_FLAG_CONTROL )
1075 /* control points are always weak */
1077 point->flags |= AF_FLAG_WEAK_INTERPOLATION;
1079 else if ( point->out_dir == point->in_dir )
1081 if ( point->out_dir != AF_DIR_NONE )
1083 /* current point lies on a horizontal or */
1084 /* vertical segment (but doesn't start or end it) */
1089 AF_Point next_u = point + point->u;
1090 AF_Point prev_v = point + point->v;
1093 if ( ft_corner_is_flat( point->fx - prev_v->fx,
1094 point->fy - prev_v->fy,
1095 next_u->fx - point->fx,
1096 next_u->fy - point->fy ) )
1098 /* either the `in' or the `out' vector is much more */
1099 /* dominant than the other one, so tag current point */
1100 /* as weak and update index deltas */
1102 prev_v->u = (FT_Pos)( next_u - prev_v );
1103 next_u->v = -prev_v->u;
1109 else if ( point->in_dir == -point->out_dir )
1111 /* current point forms a spike */
1123 /* Store the hinted outline in an FT_Outline structure. */
1125 FT_LOCAL_DEF( void )
1126 af_glyph_hints_save( AF_GlyphHints hints,
1127 FT_Outline* outline )
1129 AF_Point point = hints->points;
1130 AF_Point limit = point + hints->num_points;
1131 FT_Vector* vec = outline->points;
1132 char* tag = outline->tags;
1135 for ( ; point < limit; point++, vec++, tag++ )
1140 if ( point->flags & AF_FLAG_CONIC )
1141 tag[0] = FT_CURVE_TAG_CONIC;
1142 else if ( point->flags & AF_FLAG_CUBIC )
1143 tag[0] = FT_CURVE_TAG_CUBIC;
1145 tag[0] = FT_CURVE_TAG_ON;
1150 /****************************************************************
1152 * EDGE POINT GRID-FITTING
1154 ****************************************************************/
1157 /* Align all points of an edge to the same coordinate value, */
1158 /* either horizontally or vertically. */
1160 FT_LOCAL_DEF( void )
1161 af_glyph_hints_align_edge_points( AF_GlyphHints hints,
1164 AF_AxisHints axis = & hints->axis[dim];
1165 AF_Segment segments = axis->segments;
1166 AF_Segment segment_limit = segments + axis->num_segments;
1170 if ( dim == AF_DIMENSION_HORZ )
1172 for ( seg = segments; seg < segment_limit; seg++ )
1174 AF_Edge edge = seg->edge;
1175 AF_Point point, first, last;
1186 point->x = edge->pos;
1187 point->flags |= AF_FLAG_TOUCH_X;
1189 if ( point == last )
1192 point = point->next;
1198 for ( seg = segments; seg < segment_limit; seg++ )
1200 AF_Edge edge = seg->edge;
1201 AF_Point point, first, last;
1212 point->y = edge->pos;
1213 point->flags |= AF_FLAG_TOUCH_Y;
1215 if ( point == last )
1218 point = point->next;
1225 /****************************************************************
1227 * STRONG POINT INTERPOLATION
1229 ****************************************************************/
1232 /* Hint the strong points -- this is equivalent to the TrueType `IP' */
1233 /* hinting instruction. */
1235 FT_LOCAL_DEF( void )
1236 af_glyph_hints_align_strong_points( AF_GlyphHints hints,
1239 AF_Point points = hints->points;
1240 AF_Point point_limit = points + hints->num_points;
1241 AF_AxisHints axis = &hints->axis[dim];
1242 AF_Edge edges = axis->edges;
1243 AF_Edge edge_limit = edges + axis->num_edges;
1247 if ( dim == AF_DIMENSION_HORZ )
1248 touch_flag = AF_FLAG_TOUCH_X;
1250 touch_flag = AF_FLAG_TOUCH_Y;
1252 if ( edges < edge_limit )
1258 for ( point = points; point < point_limit; point++ )
1260 FT_Pos u, ou, fu; /* point position */
1264 if ( point->flags & touch_flag )
1267 /* if this point is candidate to weak interpolation, we */
1268 /* interpolate it after all strong points have been processed */
1270 if ( ( point->flags & AF_FLAG_WEAK_INTERPOLATION ) )
1273 if ( dim == AF_DIMENSION_VERT )
1286 /* is the point before the first edge? */
1288 delta = edge->fpos - u;
1291 u = edge->pos - ( edge->opos - ou );
1295 /* is the point after the last edge? */
1296 edge = edge_limit - 1;
1297 delta = u - edge->fpos;
1300 u = edge->pos + ( ou - edge->opos );
1305 FT_PtrDist min, max, mid;
1309 /* find enclosing edges */
1311 max = edge_limit - edges;
1314 /* for a small number of edges, a linear search is better */
1320 for ( nn = 0; nn < max; nn++ )
1321 if ( edges[nn].fpos >= u )
1324 if ( edges[nn].fpos == u )
1335 mid = ( max + min ) >> 1;
1341 else if ( u > fpos )
1345 /* we are on the edge */
1351 /* point is not on an edge */
1353 AF_Edge before = edges + min - 1;
1354 AF_Edge after = edges + min + 0;
1357 /* assert( before && after && before != after ) */
1358 if ( before->scale == 0 )
1359 before->scale = FT_DivFix( after->pos - before->pos,
1360 after->fpos - before->fpos );
1362 u = before->pos + FT_MulFix( fu - before->fpos,
1368 /* save the point position */
1369 if ( dim == AF_DIMENSION_HORZ )
1374 point->flags |= touch_flag;
1380 /****************************************************************
1382 * WEAK POINT INTERPOLATION
1384 ****************************************************************/
1387 /* Shift the original coordinates of all points between `p1' and */
1388 /* `p2' to get hinted coordinates, using the same difference as */
1389 /* given by `ref'. */
1392 af_iup_shift( AF_Point p1,
1397 FT_Pos delta = ref->u - ref->v;
1403 for ( p = p1; p < ref; p++ )
1404 p->u = p->v + delta;
1406 for ( p = ref + 1; p <= p2; p++ )
1407 p->u = p->v + delta;
1411 /* Interpolate the original coordinates of all points between `p1' and */
1412 /* `p2' to get hinted coordinates, using `ref1' and `ref2' as the */
1413 /* reference points. The `u' and `v' members are the current and */
1414 /* original coordinate values, respectively. */
1416 /* Details can be found in the TrueType bytecode specification. */
1419 af_iup_interp( AF_Point p1,
1425 FT_Pos u, v1, v2, u1, u2, d1, d2;
1431 if ( ref1->v > ref2->v )
1445 if ( u1 == u2 || v1 == v2 )
1447 for ( p = p1; p <= p2; p++ )
1463 FT_Fixed scale = FT_DivFix( u2 - u1, v2 - v1 );
1466 for ( p = p1; p <= p2; p++ )
1475 u = u1 + FT_MulFix( u - v1, scale );
1483 /* Hint the weak points -- this is equivalent to the TrueType `IUP' */
1484 /* hinting instruction. */
1486 FT_LOCAL_DEF( void )
1487 af_glyph_hints_align_weak_points( AF_GlyphHints hints,
1490 AF_Point points = hints->points;
1491 AF_Point point_limit = points + hints->num_points;
1492 AF_Point* contour = hints->contours;
1493 AF_Point* contour_limit = contour + hints->num_contours;
1497 AF_Point first_point;
1500 /* PASS 1: Move segment points to edge positions */
1502 if ( dim == AF_DIMENSION_HORZ )
1504 touch_flag = AF_FLAG_TOUCH_X;
1506 for ( point = points; point < point_limit; point++ )
1508 point->u = point->x;
1509 point->v = point->ox;
1514 touch_flag = AF_FLAG_TOUCH_Y;
1516 for ( point = points; point < point_limit; point++ )
1518 point->u = point->y;
1519 point->v = point->oy;
1523 for ( ; contour < contour_limit; contour++ )
1525 AF_Point first_touched, last_touched;
1529 end_point = point->prev;
1530 first_point = point;
1532 /* find first touched point */
1535 if ( point > end_point ) /* no touched point in contour */
1538 if ( point->flags & touch_flag )
1544 first_touched = point;
1548 FT_ASSERT( point <= end_point &&
1549 ( point->flags & touch_flag ) != 0 );
1551 /* skip any touched neighbours */
1552 while ( point < end_point &&
1553 ( point[1].flags & touch_flag ) != 0 )
1556 last_touched = point;
1558 /* find the next touched point, if any */
1562 if ( point > end_point )
1565 if ( ( point->flags & touch_flag ) != 0 )
1571 /* interpolate between last_touched and point */
1572 af_iup_interp( last_touched + 1, point - 1,
1573 last_touched, point );
1577 /* special case: only one point was touched */
1578 if ( last_touched == first_touched )
1579 af_iup_shift( first_point, end_point, first_touched );
1581 else /* interpolate the last part */
1583 if ( last_touched < end_point )
1584 af_iup_interp( last_touched + 1, end_point,
1585 last_touched, first_touched );
1587 if ( first_touched > points )
1588 af_iup_interp( first_point, first_touched - 1,
1589 last_touched, first_touched );
1596 /* now save the interpolated values back to x/y */
1597 if ( dim == AF_DIMENSION_HORZ )
1599 for ( point = points; point < point_limit; point++ )
1600 point->x = point->u;
1604 for ( point = points; point < point_limit; point++ )
1605 point->y = point->u;
1610 #ifdef AF_CONFIG_OPTION_USE_WARPER
1612 /* Apply (small) warp scale and warp delta for given dimension. */
1614 FT_LOCAL_DEF( void )
1615 af_glyph_hints_scale_dim( AF_GlyphHints hints,
1620 AF_Point points = hints->points;
1621 AF_Point points_limit = points + hints->num_points;
1625 if ( dim == AF_DIMENSION_HORZ )
1627 for ( point = points; point < points_limit; point++ )
1628 point->x = FT_MulFix( point->fx, scale ) + delta;
1632 for ( point = points; point < points_limit; point++ )
1633 point->y = FT_MulFix( point->fy, scale ) + delta;
1637 #endif /* AF_CONFIG_OPTION_USE_WARPER */