diff options
Diffstat (limited to 'src/3rdparty/freetype/src/autofit/aflatin.c')
| -rw-r--r-- | src/3rdparty/freetype/src/autofit/aflatin.c | 2177 |
1 files changed, 2177 insertions, 0 deletions
diff --git a/src/3rdparty/freetype/src/autofit/aflatin.c b/src/3rdparty/freetype/src/autofit/aflatin.c new file mode 100644 index 0000000000..ba59e5b38c --- /dev/null +++ b/src/3rdparty/freetype/src/autofit/aflatin.c @@ -0,0 +1,2177 @@ +/***************************************************************************/ +/* */ +/* aflatin.c */ +/* */ +/* Auto-fitter hinting routines for latin script (body). */ +/* */ +/* Copyright 2003, 2004, 2005, 2006, 2007, 2008 by */ +/* David Turner, Robert Wilhelm, and Werner Lemberg. */ +/* */ +/* This file is part of the FreeType project, and may only be used, */ +/* modified, and distributed under the terms of the FreeType project */ +/* license, LICENSE.TXT. By continuing to use, modify, or distribute */ +/* this file you indicate that you have read the license and */ +/* understand and accept it fully. */ +/* */ +/***************************************************************************/ + + +#include "aflatin.h" +#include "aferrors.h" + + +#ifdef AF_USE_WARPER +#include "afwarp.h" +#endif + + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** L A T I N G L O B A L M E T R I C S *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + + FT_LOCAL_DEF( void ) + af_latin_metrics_init_widths( AF_LatinMetrics metrics, + FT_Face face, + FT_ULong charcode ) + { + /* scan the array of segments in each direction */ + AF_GlyphHintsRec hints[1]; + + + 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_UInt glyph_index; + int dim; + AF_LatinMetricsRec dummy[1]; + AF_Scaler scaler = &dummy->root.scaler; + + + glyph_index = FT_Get_Char_Index( face, charcode ); + if ( glyph_index == 0 ) + goto Exit; + + 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 = scaler->y_scale = 0x10000L; + scaler->x_delta = scaler->y_delta = 0; + scaler->face = face; + scaler->render_mode = FT_RENDER_MODE_NORMAL; + scaler->flags = 0; + + af_glyph_hints_rescale( hints, (AF_ScriptMetrics)dummy ); + + error = af_glyph_hints_reload( hints, &face->glyph->outline, 0 ); + 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; + + af_latin_hints_link_segments( hints, + (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; + } + } + + af_sort_widths( num_widths, axis->widths ); + 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; + } + } + + af_glyph_hints_done( hints ); + } + + + +#define AF_LATIN_MAX_TEST_CHARACTERS 12 + + + static const char* const af_latin_blue_chars[AF_LATIN_MAX_BLUES] = + { + "THEZOCQS", + "HEZLOCUS", + "fijkdbh", + "xzroesc", + "xzroesc", + "pqgjy" + }; + + + static void + af_latin_metrics_init_blues( AF_LatinMetrics metrics, + FT_Face face ) + { + FT_Pos flats [AF_LATIN_MAX_TEST_CHARACTERS]; + FT_Pos rounds[AF_LATIN_MAX_TEST_CHARACTERS]; + FT_Int num_flats; + FT_Int num_rounds; + FT_Int bb; + AF_LatinBlue blue; + FT_Error error; + AF_LatinAxis axis = &metrics->axis[AF_DIMENSION_VERT]; + FT_GlyphSlot glyph = face->glyph; + + + /* we compute the blues simply by loading each character from the */ + /* 'af_latin_blue_chars[blues]' string, then compute its top-most or */ + /* bottom-most points (depending on `AF_IS_TOP_BLUE') */ + + AF_LOG(( "blue zones computation\n" )); + AF_LOG(( "------------------------------------------------\n" )); + + for ( bb = 0; bb < AF_LATIN_BLUE_MAX; bb++ ) + { + const char* p = af_latin_blue_chars[bb]; + const char* limit = p + AF_LATIN_MAX_TEST_CHARACTERS; + FT_Pos* blue_ref; + FT_Pos* blue_shoot; + + + AF_LOG(( "blue %3d: ", bb )); + + num_flats = 0; + num_rounds = 0; + + for ( ; p < limit && *p; p++ ) + { + FT_UInt glyph_index; + FT_Int best_point, best_y, best_first, best_last; + FT_Vector* points; + FT_Bool round = 0; + + + AF_LOG(( "'%c'", *p )); + + /* load the character in the face -- skip unknown or empty ones */ + glyph_index = FT_Get_Char_Index( face, (FT_UInt)*p ); + if ( glyph_index == 0 ) + continue; + + error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE ); + if ( error || glyph->outline.n_points <= 0 ) + continue; + + /* now compute min or max point indices and coordinates */ + points = glyph->outline.points; + best_point = -1; + best_y = 0; /* make compiler happy */ + best_first = 0; /* ditto */ + best_last = 0; /* ditto */ + + { + FT_Int nn; + FT_Int first = 0; + FT_Int last = -1; + + + for ( nn = 0; nn < glyph->outline.n_contours; first = last+1, nn++ ) + { + FT_Int old_best_point = best_point; + FT_Int pp; + + + last = glyph->outline.contours[nn]; + + /* Avoid single-point contours since they are never rasterized. */ + /* In some fonts, they correspond to mark attachment points */ + /* which are way outside of the glyph's real outline. */ + if ( last <= first ) + continue; + + if ( AF_LATIN_IS_TOP_BLUE( bb ) ) + { + for ( pp = first; pp <= last; pp++ ) + if ( best_point < 0 || points[pp].y > best_y ) + { + best_point = pp; + best_y = points[pp].y; + } + } + else + { + for ( pp = first; pp <= last; pp++ ) + if ( best_point < 0 || points[pp].y < best_y ) + { + best_point = pp; + best_y = points[pp].y; + } + } + + if ( best_point != old_best_point ) + { + best_first = first; + best_last = last; + } + } + AF_LOG(( "%5d", best_y )); + } + + /* now check whether the point belongs to a straight or round */ + /* segment; we first need to find in which contour the extremum */ + /* lies, then inspect its previous and next points */ + if ( best_point >= 0 ) + { + FT_Int prev, next; + FT_Pos dist; + + + /* now look for the previous and next points that are not on the */ + /* same Y coordinate. Threshold the `closeness'... */ + prev = best_point; + next = prev; + + do + { + if ( prev > best_first ) + prev--; + else + prev = best_last; + + dist = points[prev].y - best_y; + if ( dist < -5 || dist > 5 ) + break; + + } while ( prev != best_point ); + + do + { + if ( next < best_last ) + next++; + else + next = best_first; + + dist = points[next].y - best_y; + if ( dist < -5 || dist > 5 ) + break; + + } while ( next != best_point ); + + /* now, set the `round' flag depending on the segment's kind */ + round = FT_BOOL( + FT_CURVE_TAG( glyph->outline.tags[prev] ) != FT_CURVE_TAG_ON || + FT_CURVE_TAG( glyph->outline.tags[next] ) != FT_CURVE_TAG_ON ); + + AF_LOG(( "%c ", round ? 'r' : 'f' )); + } + + if ( round ) + rounds[num_rounds++] = best_y; + else + flats[num_flats++] = best_y; + } + + AF_LOG(( "\n" )); + + if ( num_flats == 0 && num_rounds == 0 ) + { + /* + * we couldn't find a single glyph to compute this blue zone, + * we will simply ignore it then + */ + AF_LOG(( "empty!\n" )); + continue; + } + + /* we have computed the contents of the `rounds' and `flats' tables, */ + /* now determine the reference and overshoot position of the blue -- */ + /* we simply take the median value after a simple sort */ + af_sort_pos( num_rounds, rounds ); + af_sort_pos( num_flats, flats ); + + blue = & axis->blues[axis->blue_count]; + blue_ref = & blue->ref.org; + blue_shoot = & blue->shoot.org; + + axis->blue_count++; + + if ( num_flats == 0 ) + { + *blue_ref = + *blue_shoot = rounds[num_rounds / 2]; + } + else if ( num_rounds == 0 ) + { + *blue_ref = + *blue_shoot = flats[num_flats / 2]; + } + else + { + *blue_ref = flats[num_flats / 2]; + *blue_shoot = rounds[num_rounds / 2]; + } + + /* there are sometimes problems: if the overshoot position of top */ + /* zones is under its reference position, or the opposite for bottom */ + /* zones. We must thus check everything there and correct the errors */ + if ( *blue_shoot != *blue_ref ) + { + FT_Pos ref = *blue_ref; + FT_Pos shoot = *blue_shoot; + FT_Bool over_ref = FT_BOOL( shoot > ref ); + + + if ( AF_LATIN_IS_TOP_BLUE( bb ) ^ over_ref ) + *blue_shoot = *blue_ref = ( shoot + ref ) / 2; + } + + blue->flags = 0; + if ( AF_LATIN_IS_TOP_BLUE( bb ) ) + blue->flags |= AF_LATIN_BLUE_TOP; + + /* + * The following flags is used later to adjust the y and x scales + * in order to optimize the pixel grid alignment of the top of small + * letters. + */ + if ( bb == AF_LATIN_BLUE_SMALL_TOP ) + blue->flags |= AF_LATIN_BLUE_ADJUSTMENT; + + AF_LOG(( "-- ref = %ld, shoot = %ld\n", *blue_ref, *blue_shoot )); + } + + return; + } + + + FT_LOCAL_DEF( FT_Error ) + af_latin_metrics_init( AF_LatinMetrics metrics, + FT_Face face ) + { + FT_Error error = AF_Err_Ok; + FT_CharMap oldmap = face->charmap; + FT_UInt ee; + + static const FT_Encoding latin_encodings[] = + { + FT_ENCODING_UNICODE, + FT_ENCODING_APPLE_ROMAN, + FT_ENCODING_ADOBE_STANDARD, + FT_ENCODING_ADOBE_LATIN_1, + FT_ENCODING_NONE /* end of list */ + }; + + + metrics->units_per_em = face->units_per_EM; + + /* do we have a latin charmap in there? */ + for ( ee = 0; latin_encodings[ee] != FT_ENCODING_NONE; ee++ ) + { + error = FT_Select_Charmap( face, latin_encodings[ee] ); + if ( !error ) + break; + } + + if ( !error ) + { + /* For now, compute the standard width and height from the `o'. */ + af_latin_metrics_init_widths( metrics, face, 'o' ); + af_latin_metrics_init_blues( metrics, face ); + } + + FT_Set_Charmap( face, oldmap ); + return AF_Err_Ok; + } + + + static void + af_latin_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 X and Y scale to optimize the alignment of the top of small + * letters to the pixel grid + */ + { + AF_LatinAxis Axis = &metrics->axis[AF_DIMENSION_VERT]; + AF_LatinBlue blue = NULL; + + + for ( nn = 0; nn < Axis->blue_count; nn++ ) + { + if ( Axis->blues[nn].flags & AF_LATIN_BLUE_ADJUSTMENT ) + { + blue = &Axis->blues[nn]; + break; + } + } + + if ( blue ) + { + FT_Pos scaled = FT_MulFix( blue->shoot.org, scaler->y_scale ); + FT_Pos fitted = ( scaled + 40 ) & ~63; + + + if ( scaled != fitted ) + { +#if 0 + if ( dim == AF_DIMENSION_HORZ ) + { + if ( fitted < scaled ) + scale -= scale / 50; /* scale *= 0.98 */ + } + else +#endif + if ( dim == AF_DIMENSION_VERT ) + { + scale = FT_MulDiv( scale, fitted, scaled ); + } + } + } + } + + 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; + + blue->flags |= AF_LATIN_BLUE_ACTIVE; + } + } + } + } + + + FT_LOCAL_DEF( void ) + af_latin_metrics_scale( AF_LatinMetrics metrics, + AF_Scaler scaler ) + { + metrics->root.scaler.render_mode = scaler->render_mode; + metrics->root.scaler.face = scaler->face; + + af_latin_metrics_scale_dim( metrics, scaler, AF_DIMENSION_HORZ ); + af_latin_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 *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + + FT_LOCAL_DEF( FT_Error ) + af_latin_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 last = point->prev; + int on_edge = 0; + FT_Pos min_pos = 32000; /* minimum segment pos != min_coord */ + FT_Pos max_pos = -32000; /* maximum segment pos != max_coord */ + FT_Bool passed; + + + if ( point == last ) /* skip singletons -- just in case */ + continue; + + 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 ) + { + u = point->u; + if ( u < min_pos ) + min_pos = u; + if ( u > max_pos ) + max_pos = u; + + if ( point->out_dir != segment_dir || point == last ) + { + /* we are just leaving an edge; record a new segment! */ + segment->last = point; + segment->pos = (FT_Short)( ( min_pos + max_pos ) >> 1 ); + + /* a segment is round if either its first or last point */ + /* is a control point */ + if ( ( segment->first->flags | point->flags ) & + AF_FLAG_CONTROL ) + segment->flags |= AF_EDGE_ROUND; + + /* compute segment size */ + min_pos = max_pos = point->v; + + v = segment->first->v; + if ( v < min_pos ) + min_pos = v; + if ( v > max_pos ) + max_pos = v; + + segment->min_coord = (FT_Short)min_pos; + segment->max_coord = (FT_Short)max_pos; + segment->height = (FT_Short)( segment->max_coord - + segment->min_coord ); + + on_edge = 0; + segment = NULL; + /* fallthrough */ + } + } + + /* now exit if we are at the start/end point */ + if ( point == last ) + { + if ( passed ) + break; + passed = 1; + } + + if ( !on_edge && FT_ABS( point->out_dir ) == major_dir ) + { + /* this is the start of a new segment! */ + segment_dir = (AF_Direction)point->out_dir; + + /* clear all segment fields */ + error = af_axis_hints_new_segment( axis, memory, &segment ); + if ( error ) + goto Exit; + + segment[0] = seg0; + segment->dir = (FT_Char)segment_dir; + min_pos = max_pos = point->u; + segment->first = point; + segment->last = point; + segment->contour = contour; + on_edge = 1; + } + + point = point->next; + } + + } /* 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; + FT_Pos first_v = first->v; + FT_Pos last_v = last->v; + + + if ( first == last ) + continue; + + 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; + } + + + FT_LOCAL_DEF( void ) + af_latin_hints_link_segments( AF_GlyphHints hints, + AF_Dimension dim ) + { + 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; + AF_Segment seg1, seg2; + + + len_threshold = AF_LATIN_CONSTANT( hints->metrics, 8 ); + if ( len_threshold == 0 ) + len_threshold = 1; + + len_score = AF_LATIN_CONSTANT( hints->metrics, 6000 ); + + /* now compare each segment to the others */ + for ( seg1 = segments; seg1 < segment_limit; seg1++ ) + { + /* the fake segments are introduced to hint the metrics -- */ + /* we must never link them to anything */ + if ( seg1->dir != axis->major_dir || seg1->first == seg1->last ) + continue; + + for ( seg2 = segments; seg2 < segment_limit; seg2++ ) + if ( seg1->dir + seg2->dir == 0 && seg2->pos > seg1->pos ) + { + FT_Pos pos1 = seg1->pos; + FT_Pos pos2 = seg2->pos; + FT_Pos dist = pos2 - pos1; + + + if ( dist < 0 ) + dist = -dist; + + { + FT_Pos min = seg1->min_coord; + FT_Pos max = seg1->max_coord; + FT_Pos len, score; + + + if ( min < seg2->min_coord ) + min = seg2->min_coord; + + if ( max > seg2->max_coord ) + max = seg2->max_coord; + + len = max - min; + if ( len >= len_threshold ) + { + score = dist + len_score / len; + + 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 */ + for ( seg1 = segments; seg1 < segment_limit; seg1++ ) + { + seg2 = seg1->link; + + if ( seg2 ) + { + if ( seg2->link != seg1 ) + { + seg1->link = 0; + seg1->serif = seg2->link; + } + } + } + } + + + FT_LOCAL_DEF( FT_Error ) + af_latin_hints_compute_edges( AF_GlyphHints hints, + AF_Dimension dim ) + { + AF_AxisHints axis = &hints->axis[dim]; + FT_Error error = AF_Err_Ok; + FT_Memory memory = hints->memory; + AF_LatinAxis laxis = &((AF_LatinMetrics)hints->metrics)->axis[dim]; + + AF_Segment segments = axis->segments; + AF_Segment segment_limit = segments + axis->num_segments; + AF_Segment seg; + + AF_Direction up_dir; + FT_Fixed scale; + FT_Pos edge_distance_threshold; + FT_Pos segment_length_threshold; + + + axis->num_edges = 0; + + scale = ( dim == AF_DIMENSION_HORZ ) ? hints->x_scale + : hints->y_scale; + + up_dir = ( dim == AF_DIMENSION_HORZ ) ? AF_DIR_UP + : AF_DIR_RIGHT; + + /* + * We ignore all segments that are less than 1 pixels 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; + + /*********************************************************************/ + /* */ + /* We will 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 will be processed in the second step to compute the */ + /* edge's properties. */ + /* */ + /* Note that the edges table is sorted along the segment/edge */ + /* position. */ + /* */ + /*********************************************************************/ + + 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 = 0; + FT_Int ee; + + + if ( seg->height < segment_length_threshold ) + 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, + 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->fpos = seg->pos; + edge->dir = seg->dir; + edge->opos = edge->pos = FT_MulFix( seg->pos, scale ); + 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; + } + } + + + /*********************************************************************/ + /* */ + /* Good, we will now compute each edge's properties according to */ + /* segments found on its position. Basically, these are: */ + /* */ + /* - 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? */ + FT_Pos ups = 0; /* number of upwards segments */ + FT_Pos downs = 0; /* number of downwards segments */ + + + seg = edge->first; + + do + { + FT_Bool is_serif; + + + /* check for roundness of segment */ + if ( seg->flags & AF_EDGE_ROUND ) + is_round++; + else + is_straight++; + + /* check for segment direction */ + if ( seg->dir == up_dir ) + ups += seg->max_coord-seg->min_coord; + else + downs += seg->max_coord-seg->min_coord; + + /* 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 != NULL ) || 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 + + /* gets 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 = 0; + } + } + + Exit: + return error; + } + + + FT_LOCAL_DEF( FT_Error ) + af_latin_hints_detect_features( AF_GlyphHints hints, + AF_Dimension dim ) + { + FT_Error error; + + + error = af_latin_hints_compute_segments( hints, dim ); + if ( !error ) + { + af_latin_hints_link_segments( hints, dim ); + + error = af_latin_hints_compute_edges( hints, dim ); + } + return error; + } + + + FT_LOCAL_DEF( void ) + af_latin_hints_compute_blue_edges( AF_GlyphHints hints, + AF_LatinMetrics metrics ) + { + AF_AxisHints axis = &hints->axis[ AF_DIMENSION_VERT ]; + AF_Edge edge = axis->edges; + AF_Edge edge_limit = edge + axis->num_edges; + AF_LatinAxis latin = &metrics->axis[ AF_DIMENSION_VERT ]; + FT_Fixed scale = latin->scale; + + + /* compute which blue zones are active, i.e. have their scaled */ + /* size < 3/4 pixels */ + + /* for each horizontal edge search the blue zone which is closest */ + for ( ; edge < edge_limit; edge++ ) + { + FT_Int bb; + AF_Width best_blue = NULL; + FT_Pos best_dist; /* initial threshold */ + + + /* compute the initial threshold as a fraction of the EM size */ + best_dist = FT_MulFix( metrics->units_per_em / 40, scale ); + + if ( best_dist > 64 / 2 ) + best_dist = 64 / 2; + + for ( bb = 0; bb < AF_LATIN_BLUE_MAX; bb++ ) + { + AF_LatinBlue blue = latin->blues + bb; + FT_Bool is_top_blue, is_major_dir; + + + /* skip inactive blue zones (i.e., those that are too small) */ + if ( !( blue->flags & AF_LATIN_BLUE_ACTIVE ) ) + continue; + + /* if it is a top zone, check for right edges -- if it is a bottom */ + /* zone, check for left edges */ + /* */ + /* of course, that's for TrueType */ + is_top_blue = (FT_Byte)( ( blue->flags & AF_LATIN_BLUE_TOP ) != 0 ); + is_major_dir = FT_BOOL( edge->dir == axis->major_dir ); + + /* if it is a top zone, the edge must be against the major */ + /* direction; if it is a bottom zone, it must be in the major */ + /* direction */ + if ( is_top_blue ^ is_major_dir ) + { + FT_Pos dist; + + + /* first of all, compare it to the reference position */ + dist = edge->fpos - blue->ref.org; + if ( dist < 0 ) + dist = -dist; + + dist = FT_MulFix( dist, scale ); + if ( dist < best_dist ) + { + best_dist = dist; + best_blue = & blue->ref; + } + + /* now, compare it to the overshoot position if the edge is */ + /* rounded, and if the edge is over the reference position of a */ + /* top zone, or under the reference position of a bottom zone */ + if ( edge->flags & AF_EDGE_ROUND && dist != 0 ) + { + FT_Bool is_under_ref = FT_BOOL( edge->fpos < blue->ref.org ); + + + if ( is_top_blue ^ is_under_ref ) + { + blue = latin->blues + bb; + dist = edge->fpos - blue->shoot.org; + if ( dist < 0 ) + dist = -dist; + + dist = FT_MulFix( dist, scale ); + if ( dist < best_dist ) + { + best_dist = dist; + best_blue = & blue->shoot; + } + } + } + } + } + + if ( best_blue ) + edge->blue_edge = best_blue; + } + } + + + static FT_Error + af_latin_hints_init( AF_GlyphHints hints, + AF_LatinMetrics metrics ) + { + FT_Render_Mode mode; + FT_UInt32 scaler_flags, other_flags; + FT_Face face = metrics->root.scaler.face; + + + af_glyph_hints_rescale( hints, (AF_ScriptMetrics)metrics ); + + /* + * correct x_scale and y_scale if needed, since they may have + * been modified `af_latin_metrics_scale_dim' above + */ + hints->x_scale = metrics->axis[AF_DIMENSION_HORZ].scale; + hints->x_delta = metrics->axis[AF_DIMENSION_HORZ].delta; + hints->y_scale = metrics->axis[AF_DIMENSION_VERT].scale; + hints->y_delta = metrics->axis[AF_DIMENSION_VERT].delta; + + /* compute flags depending on render mode, etc. */ + mode = metrics->root.scaler.render_mode; + +#if 0 /* #ifdef AF_USE_WARPER */ + if ( mode == FT_RENDER_MODE_LCD || mode == FT_RENDER_MODE_LCD_V ) + { + metrics->root.scaler.render_mode = mode = FT_RENDER_MODE_NORMAL; + } +#endif + + scaler_flags = hints->scaler_flags; + other_flags = 0; + + /* + * We snap the width of vertical stems for the monochrome and + * horizontal LCD rendering targets only. + */ + if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD ) + other_flags |= AF_LATIN_HINTS_HORZ_SNAP; + + /* + * We snap the width of horizontal stems for the monochrome and + * vertical LCD rendering targets only. + */ + if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD_V ) + other_flags |= AF_LATIN_HINTS_VERT_SNAP; + + /* + * We adjust stems to full pixels only if we don't use the `light' mode. + */ + if ( mode != FT_RENDER_MODE_LIGHT ) + other_flags |= AF_LATIN_HINTS_STEM_ADJUST; + + if ( mode == FT_RENDER_MODE_MONO ) + other_flags |= AF_LATIN_HINTS_MONO; + + /* + * In `light' hinting mode we disable horizontal hinting completely. + * We also do it if the face is italic. + */ + if ( mode == FT_RENDER_MODE_LIGHT || + (face->style_flags & FT_STYLE_FLAG_ITALIC) != 0 ) + scaler_flags |= AF_SCALER_FLAG_NO_HORIZONTAL; + + hints->scaler_flags = scaler_flags; + hints->other_flags = other_flags; + + return 0; + } + + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** L A T I N G L Y P H G R I D - F I T T I N G *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + + /* snap a given width in scaled coordinates to one of the */ + /* current standard widths */ + + static FT_Pos + af_latin_snap_width( AF_Width widths, + FT_Int count, + FT_Pos width ) + { + int n; + FT_Pos best = 64 + 32 + 2; + FT_Pos reference = width; + FT_Pos scaled; + + + for ( n = 0; n < count; n++ ) + { + FT_Pos w; + FT_Pos dist; + + + w = widths[n].cur; + dist = width - w; + if ( dist < 0 ) + dist = -dist; + if ( dist < best ) + { + best = dist; + reference = w; + } + } + + scaled = FT_PIX_ROUND( reference ); + + if ( width >= reference ) + { + if ( width < scaled + 48 ) + width = reference; + } + else + { + if ( width > scaled - 48 ) + width = reference; + } + + return width; + } + + + /* compute the snapped width of a given stem */ + + static FT_Pos + af_latin_compute_stem_width( AF_GlyphHints hints, + AF_Dimension dim, + FT_Pos width, + AF_Edge_Flags base_flags, + AF_Edge_Flags stem_flags ) + { + AF_LatinMetrics metrics = (AF_LatinMetrics) hints->metrics; + AF_LatinAxis axis = & metrics->axis[dim]; + FT_Pos dist = width; + FT_Int sign = 0; + FT_Int vertical = ( dim == AF_DIMENSION_VERT ); + + + if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) || + axis->extra_light ) + return width; + + if ( dist < 0 ) + { + dist = -width; + sign = 1; + } + + if ( ( vertical && !AF_LATIN_HINTS_DO_VERT_SNAP( hints ) ) || + ( !vertical && !AF_LATIN_HINTS_DO_HORZ_SNAP( hints ) ) ) + { + /* smooth hinting process: very lightly quantize the stem width */ + + /* leave the widths of serifs alone */ + + if ( ( stem_flags & AF_EDGE_SERIF ) && vertical && ( dist < 3 * 64 ) ) + goto Done_Width; + + else if ( ( base_flags & AF_EDGE_ROUND ) ) + { + if ( dist < 80 ) + dist = 64; + } + else if ( dist < 56 ) + dist = 56; + + if ( axis->width_count > 0 ) + { + FT_Pos delta; + + + /* compare to standard width */ + if ( axis->width_count > 0 ) + { + delta = dist - axis->widths[0].cur; + + if ( delta < 0 ) + delta = -delta; + + if ( delta < 40 ) + { + dist = axis->widths[0].cur; + if ( dist < 48 ) + dist = 48; + + goto Done_Width; + } + } + + if ( dist < 3 * 64 ) + { + delta = dist & 63; + dist &= -64; + + if ( delta < 10 ) + dist += delta; + + else if ( delta < 32 ) + dist += 10; + + else if ( delta < 54 ) + dist += 54; + + else + dist += delta; + } + else + dist = ( dist + 32 ) & ~63; + } + } + else + { + /* strong hinting process: snap the stem width to integer pixels */ + FT_Pos org_dist = dist; + + + dist = af_latin_snap_width( axis->widths, axis->width_count, dist ); + + if ( vertical ) + { + /* in the case of vertical hinting, always round */ + /* the stem heights to integer pixels */ + + if ( dist >= 64 ) + dist = ( dist + 16 ) & ~63; + else + dist = 64; + } + else + { + if ( AF_LATIN_HINTS_DO_MONO( hints ) ) + { + /* monochrome horizontal hinting: snap widths to integer pixels */ + /* with a different threshold */ + + if ( dist < 64 ) + dist = 64; + else + dist = ( dist + 32 ) & ~63; + } + else + { + /* for horizontal anti-aliased hinting, we adopt a more subtle */ + /* approach: we strengthen small stems, round stems whose size */ + /* is between 1 and 2 pixels to an integer, otherwise nothing */ + + if ( dist < 48 ) + dist = ( dist + 64 ) >> 1; + + else if ( dist < 128 ) + { + /* We only round to an integer width if the corresponding */ + /* distortion is less than 1/4 pixel. Otherwise this */ + /* makes everything worse since the diagonals, which are */ + /* not hinted, appear a lot bolder or thinner than the */ + /* vertical stems. */ + + FT_Int delta; + + + dist = ( dist + 22 ) & ~63; + delta = dist - org_dist; + if ( delta < 0 ) + delta = -delta; + + if (delta >= 16) + { + dist = org_dist; + if ( dist < 48 ) + dist = ( dist + 64 ) >> 1; + } + } + else + /* round otherwise to prevent color fringes in LCD mode */ + dist = ( dist + 32 ) & ~63; + } + } + } + + Done_Width: + if ( sign ) + dist = -dist; + + return dist; + } + + + /* align one stem edge relative to the previous stem edge */ + + static void + af_latin_align_linked_edge( AF_GlyphHints hints, + AF_Dimension dim, + AF_Edge base_edge, + AF_Edge stem_edge ) + { + FT_Pos dist = stem_edge->opos - base_edge->opos; + + FT_Pos fitted_width = af_latin_compute_stem_width( + hints, dim, dist, + (AF_Edge_Flags)base_edge->flags, + (AF_Edge_Flags)stem_edge->flags ); + + + stem_edge->pos = base_edge->pos + fitted_width; + + AF_LOG(( "LINK: edge %d (opos=%.2f) linked to (%.2f), " + "dist was %.2f, now %.2f\n", + stem_edge-hints->axis[dim].edges, stem_edge->opos / 64.0, + stem_edge->pos / 64.0, dist / 64.0, fitted_width / 64.0 )); + } + + + static void + af_latin_align_serif_edge( AF_GlyphHints hints, + AF_Edge base, + AF_Edge serif ) + { + FT_UNUSED( hints ); + + serif->pos = base->pos + (serif->opos - base->opos); + } + + + /*************************************************************************/ + /*************************************************************************/ + /*************************************************************************/ + /**** ****/ + /**** E D G E H I N T I N G ****/ + /**** ****/ + /*************************************************************************/ + /*************************************************************************/ + /*************************************************************************/ + + + FT_LOCAL_DEF( void ) + af_latin_hint_edges( AF_GlyphHints hints, + AF_Dimension dim ) + { + AF_AxisHints axis = &hints->axis[dim]; + AF_Edge edges = axis->edges; + AF_Edge edge_limit = edges + axis->num_edges; + FT_Int n_edges; + AF_Edge edge; + AF_Edge anchor = 0; + FT_Int has_serifs = 0; + + + /* we begin by aligning all stems relative to the blue zone */ + /* if needed -- that's only for horizontal edges */ + + if ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_BLUES( hints ) ) + { + for ( edge = edges; edge < edge_limit; edge++ ) + { + AF_Width blue; + AF_Edge edge1, edge2; + + + if ( edge->flags & AF_EDGE_DONE ) + continue; + + blue = edge->blue_edge; + edge1 = NULL; + edge2 = edge->link; + + if ( blue ) + { + edge1 = edge; + } + else if ( edge2 && edge2->blue_edge ) + { + blue = edge2->blue_edge; + edge1 = edge2; + edge2 = edge; + } + + if ( !edge1 ) + continue; + + AF_LOG(( "BLUE: edge %d (opos=%.2f) snapped to (%.2f), " + "was (%.2f)\n", + edge1-edges, edge1->opos / 64.0, blue->fit / 64.0, + edge1->pos / 64.0 )); + + edge1->pos = blue->fit; + edge1->flags |= AF_EDGE_DONE; + + if ( edge2 && !edge2->blue_edge ) + { + af_latin_align_linked_edge( hints, dim, edge1, edge2 ); + edge2->flags |= AF_EDGE_DONE; + } + + if ( !anchor ) + anchor = edge; + } + } + + /* now we will align all stem edges, trying to maintain the */ + /* relative order of stems in the glyph */ + for ( edge = edges; edge < edge_limit; edge++ ) + { + AF_Edge edge2; + + + if ( edge->flags & AF_EDGE_DONE ) + continue; + + /* skip all non-stem edges */ + edge2 = edge->link; + if ( !edge2 ) + { + has_serifs++; + continue; + } + + /* now align the stem */ + + /* this should not happen, but it's better to be safe */ + if ( edge2->blue_edge ) + { + AF_LOG(( "ASSERTION FAILED for edge %d\n", edge2-edges )); + + af_latin_align_linked_edge( hints, dim, edge2, edge ); + edge->flags |= AF_EDGE_DONE; + continue; + } + + if ( !anchor ) + { + FT_Pos org_len, org_center, cur_len; + FT_Pos cur_pos1, error1, error2, u_off, d_off; + + + org_len = edge2->opos - edge->opos; + cur_len = af_latin_compute_stem_width( + hints, dim, org_len, + (AF_Edge_Flags)edge->flags, + (AF_Edge_Flags)edge2->flags ); + if ( cur_len <= 64 ) + u_off = d_off = 32; + else + { + u_off = 38; + d_off = 26; + } + + if ( cur_len < 96 ) + { + org_center = edge->opos + ( org_len >> 1 ); + + cur_pos1 = FT_PIX_ROUND( org_center ); + + error1 = org_center - ( cur_pos1 - u_off ); + if ( error1 < 0 ) + error1 = -error1; + + error2 = org_center - ( cur_pos1 + d_off ); + if ( error2 < 0 ) + error2 = -error2; + + if ( error1 < error2 ) + cur_pos1 -= u_off; + else + cur_pos1 += d_off; + + edge->pos = cur_pos1 - cur_len / 2; + edge2->pos = edge->pos + cur_len; + } + else + edge->pos = FT_PIX_ROUND( edge->opos ); + + AF_LOG(( "ANCHOR: edge %d (opos=%.2f) and %d (opos=%.2f) " + "snapped to (%.2f) (%.2f)\n", + edge-edges, edge->opos / 64.0, + edge2-edges, edge2->opos / 64.0, + edge->pos / 64.0, edge2->pos / 64.0 )); + anchor = edge; + + edge->flags |= AF_EDGE_DONE; + + af_latin_align_linked_edge( hints, dim, edge, edge2 ); + } + else + { + FT_Pos org_pos, org_len, org_center, cur_len; + FT_Pos cur_pos1, cur_pos2, delta1, delta2; + + + org_pos = anchor->pos + ( edge->opos - anchor->opos ); + org_len = edge2->opos - edge->opos; + org_center = org_pos + ( org_len >> 1 ); + + cur_len = af_latin_compute_stem_width( + hints, dim, org_len, + (AF_Edge_Flags)edge->flags, + (AF_Edge_Flags)edge2->flags ); + + if ( edge2->flags & AF_EDGE_DONE ) + edge->pos = edge2->pos - cur_len; + + else if ( cur_len < 96 ) + { + FT_Pos u_off, d_off; + + + cur_pos1 = FT_PIX_ROUND( org_center ); + + if (cur_len <= 64 ) + u_off = d_off = 32; + else + { + u_off = 38; + d_off = 26; + } + + delta1 = org_center - ( cur_pos1 - u_off ); + if ( delta1 < 0 ) + delta1 = -delta1; + + delta2 = org_center - ( cur_pos1 + d_off ); + if ( delta2 < 0 ) + delta2 = -delta2; + + if ( delta1 < delta2 ) + cur_pos1 -= u_off; + else + cur_pos1 += d_off; + + edge->pos = cur_pos1 - cur_len / 2; + edge2->pos = cur_pos1 + cur_len / 2; + + AF_LOG(( "STEM: %d (opos=%.2f) to %d (opos=%.2f) " + "snapped to (%.2f) and (%.2f)\n", + edge-edges, edge->opos / 64.0, + edge2-edges, edge2->opos / 64.0, + edge->pos / 64.0, edge2->pos / 64.0 )); + } + else + { + org_pos = anchor->pos + ( edge->opos - anchor->opos ); + org_len = edge2->opos - edge->opos; + org_center = org_pos + ( org_len >> 1 ); + + cur_len = af_latin_compute_stem_width( + hints, dim, org_len, + (AF_Edge_Flags)edge->flags, + (AF_Edge_Flags)edge2->flags ); + + cur_pos1 = FT_PIX_ROUND( org_pos ); + delta1 = cur_pos1 + ( cur_len >> 1 ) - org_center; + if ( delta1 < 0 ) + delta1 = -delta1; + + cur_pos2 = FT_PIX_ROUND( org_pos + org_len ) - cur_len; + delta2 = cur_pos2 + ( cur_len >> 1 ) - org_center; + if ( delta2 < 0 ) + delta2 = -delta2; + + edge->pos = ( delta1 < delta2 ) ? cur_pos1 : cur_pos2; + edge2->pos = edge->pos + cur_len; + + AF_LOG(( "STEM: %d (opos=%.2f) to %d (opos=%.2f) " + "snapped to (%.2f) and (%.2f)\n", + edge-edges, edge->opos / 64.0, + edge2-edges, edge2->opos / 64.0, + edge->pos / 64.0, edge2->pos / 64.0 )); + } + + edge->flags |= AF_EDGE_DONE; + edge2->flags |= AF_EDGE_DONE; + + if ( edge > edges && edge->pos < edge[-1].pos ) + { + AF_LOG(( "BOUND: %d (pos=%.2f) to (%.2f)\n", + edge-edges, edge->pos / 64.0, edge[-1].pos / 64.0 )); + edge->pos = edge[-1].pos; + } + } + } + + /* make sure that lowercase m's maintain their symmetry */ + + /* In general, lowercase m's have six vertical edges if they are sans */ + /* serif, or twelve if they are with serifs. This implementation is */ + /* based on that assumption, and seems to work very well with most */ + /* faces. However, if for a certain face this assumption is not */ + /* true, the m is just rendered like before. In addition, any stem */ + /* correction will only be applied to symmetrical glyphs (even if the */ + /* glyph is not an m), so the potential for unwanted distortion is */ + /* relatively low. */ + + /* We don't handle horizontal edges since we can't easily assure that */ + /* the third (lowest) stem aligns with the base line; it might end up */ + /* one pixel higher or lower. */ + + n_edges = edge_limit - edges; + if ( dim == AF_DIMENSION_HORZ && ( n_edges == 6 || n_edges == 12 ) ) + { + AF_Edge edge1, edge2, edge3; + FT_Pos dist1, dist2, span, delta; + + + if ( n_edges == 6 ) + { + edge1 = edges; + edge2 = edges + 2; + edge3 = edges + 4; + } + else + { + edge1 = edges + 1; + edge2 = edges + 5; + edge3 = edges + 9; + } + + dist1 = edge2->opos - edge1->opos; + dist2 = edge3->opos - edge2->opos; + + span = dist1 - dist2; + if ( span < 0 ) + span = -span; + + if ( span < 8 ) + { + delta = edge3->pos - ( 2 * edge2->pos - edge1->pos ); + edge3->pos -= delta; + if ( edge3->link ) + edge3->link->pos -= delta; + + /* move the serifs along with the stem */ + if ( n_edges == 12 ) + { + ( edges + 8 )->pos -= delta; + ( edges + 11 )->pos -= delta; + } + + edge3->flags |= AF_EDGE_DONE; + if ( edge3->link ) + edge3->link->flags |= AF_EDGE_DONE; + } + } + + if ( has_serifs || !anchor ) + { + /* + * now hint the remaining edges (serifs and single) in order + * to complete our processing + */ + for ( edge = edges; edge < edge_limit; edge++ ) + { + FT_Pos delta; + + + if ( edge->flags & AF_EDGE_DONE ) + continue; + + delta = 1000; + + if ( edge->serif ) + { + delta = edge->serif->opos - edge->opos; + if ( delta < 0 ) + delta = -delta; + } + + if ( delta < 64 + 16 ) + { + af_latin_align_serif_edge( hints, edge->serif, edge ); + AF_LOG(( "SERIF: edge %d (opos=%.2f) serif to %d (opos=%.2f) " + "aligned to (%.2f)\n", + edge-edges, edge->opos / 64.0, + edge->serif - edges, edge->serif->opos / 64.0, + edge->pos / 64.0 )); + } + else if ( !anchor ) + { + AF_LOG(( "SERIF_ANCHOR: edge %d (opos=%.2f) snapped to (%.2f)\n", + edge-edges, edge->opos / 64.0, edge->pos / 64.0 )); + edge->pos = FT_PIX_ROUND( edge->opos ); + anchor = edge; + } + else + { + AF_Edge before, after; + + + for ( before = edge - 1; before >= edges; before-- ) + if ( before->flags & AF_EDGE_DONE ) + break; + + for ( after = edge + 1; after < edge_limit; after++ ) + if ( after->flags & AF_EDGE_DONE ) + break; + + if ( before >= edges && before < edge && + after < edge_limit && after > edge ) + { + if ( after->opos == before->opos ) + edge->pos = before->pos; + else + edge->pos = before->pos + + FT_MulDiv( edge->opos - before->opos, + after->pos - before->pos, + after->opos - before->opos ); + AF_LOG(( "SERIF_LINK1: edge %d (opos=%.2f) snapped to (%.2f) " + "from %d (opos=%.2f)\n", + edge-edges, edge->opos / 64.0, + edge->pos / 64.0, before - edges, + before->opos / 64.0 )); + } + else + { + edge->pos = anchor->pos + + ( ( edge->opos - anchor->opos + 16 ) & ~31 ); + AF_LOG(( "SERIF_LINK2: edge %d (opos=%.2f) snapped to (%.2f)\n", + edge-edges, edge->opos / 64.0, edge->pos / 64.0 )); + } + } + + edge->flags |= AF_EDGE_DONE; + + if ( edge > edges && edge->pos < edge[-1].pos ) + edge->pos = edge[-1].pos; + + if ( edge + 1 < edge_limit && + edge[1].flags & AF_EDGE_DONE && + edge->pos > edge[1].pos ) + edge->pos = edge[1].pos; + } + } + } + + + static FT_Error + af_latin_hints_apply( AF_GlyphHints hints, + FT_Outline* outline, + AF_LatinMetrics metrics ) + { + FT_Error error; + int dim; + + + error = af_glyph_hints_reload( hints, outline, 1 ); + if ( error ) + goto Exit; + + /* analyze glyph outline */ +#ifdef AF_USE_WARPER + if ( metrics->root.scaler.render_mode == FT_RENDER_MODE_LIGHT || + AF_HINTS_DO_HORIZONTAL( hints ) ) +#else + if ( AF_HINTS_DO_HORIZONTAL( hints ) ) +#endif + { + error = af_latin_hints_detect_features( hints, AF_DIMENSION_HORZ ); + if ( error ) + goto Exit; + } + + if ( AF_HINTS_DO_VERTICAL( hints ) ) + { + error = af_latin_hints_detect_features( hints, AF_DIMENSION_VERT ); + if ( error ) + goto Exit; + + af_latin_hints_compute_blue_edges( hints, metrics ); + } + + /* grid-fit the outline */ + for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ ) + { +#ifdef AF_USE_WARPER + if ( ( dim == AF_DIMENSION_HORZ && + metrics->root.scaler.render_mode == FT_RENDER_MODE_LIGHT ) ) + { + AF_WarperRec warper; + FT_Fixed scale; + FT_Pos delta; + + + af_warper_compute( &warper, hints, dim, &scale, &delta ); + af_glyph_hints_scale_dim( hints, dim, scale, delta ); + continue; + } +#endif + + if ( ( dim == AF_DIMENSION_HORZ && AF_HINTS_DO_HORIZONTAL( hints ) ) || + ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_VERTICAL( hints ) ) ) + { + af_latin_hint_edges( hints, (AF_Dimension)dim ); + af_glyph_hints_align_edge_points( hints, (AF_Dimension)dim ); + af_glyph_hints_align_strong_points( hints, (AF_Dimension)dim ); + af_glyph_hints_align_weak_points( hints, (AF_Dimension)dim ); + } + } + af_glyph_hints_save( hints, outline ); + + Exit: + return error; + } + + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** L A T I N S C R I P T C L A S S *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + + + /* XXX: this should probably fine tuned to differentiate better between */ + /* scripts... */ + + static const AF_Script_UniRangeRec af_latin_uniranges[] = + { + { 0x0020 , 0x007F }, /* Basic Latin (no control chars) */ + { 0x00A0 , 0x00FF }, /* Latin-1 Supplement (no control chars) */ + { 0x0100 , 0x017F }, /* Latin Extended-A */ + { 0x0180 , 0x024F }, /* Latin Extended-B */ + { 0x0250 , 0x02AF }, /* IPA Extensions */ + { 0x02B0 , 0x02FF }, /* Spacing Modifier Letters */ + { 0x0300 , 0x036F }, /* Combining Diacritical Marks */ + { 0x0370 , 0x03FF }, /* Greek and Coptic */ + { 0x0400 , 0x04FF }, /* Cyrillic */ + { 0x0500 , 0x052F }, /* Cyrillic Supplement */ + { 0x1D00 , 0x1D7F }, /* Phonetic Extensions */ + { 0x1D80 , 0x1DBF }, /* Phonetic Extensions Supplement */ + { 0x1DC0 , 0x1DFF }, /* Combining Diacritical Marks Supplement */ + { 0x1E00 , 0x1EFF }, /* Latin Extended Additional */ + { 0x1F00 , 0x1FFF }, /* Greek Extended */ + { 0x2000 , 0x206F }, /* General Punctuation */ + { 0x2070 , 0x209F }, /* Superscripts and Subscripts */ + { 0x20A0 , 0x20CF }, /* Currency Symbols */ + { 0x2150 , 0x218F }, /* Number Forms */ + { 0x2460 , 0x24FF }, /* Enclosed Alphanumerics */ + { 0x2C60 , 0x2C7F }, /* Latin Extended-C */ + { 0x2DE0 , 0x2DFF }, /* Cyrillic Extended-A */ + { 0xA640U , 0xA69FU }, /* Cyrillic Extended-B */ + { 0xA720U , 0xA7FFU }, /* Latin Extended-D */ + { 0xFB00U , 0xFB06U }, /* Alphab. Present. Forms (Latin Ligs) */ + { 0x1D400UL, 0x1D7FFUL }, /* Mathematical Alphanumeric Symbols */ + { 0 , 0 } + }; + + + FT_CALLBACK_TABLE_DEF const AF_ScriptClassRec + af_latin_script_class = + { + AF_SCRIPT_LATIN, + af_latin_uniranges, + + sizeof( AF_LatinMetricsRec ), + + (AF_Script_InitMetricsFunc) af_latin_metrics_init, + (AF_Script_ScaleMetricsFunc)af_latin_metrics_scale, + (AF_Script_DoneMetricsFunc) NULL, + + (AF_Script_InitHintsFunc) af_latin_hints_init, + (AF_Script_ApplyHintsFunc) af_latin_hints_apply + }; + + +/* END */ |