| /***************************************************************************/ |
| /* */ |
| /* afcjk.c */ |
| /* */ |
| /* Auto-fitter hinting routines for CJK script (body). */ |
| /* */ |
| /* Copyright 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. */ |
| /* */ |
| /***************************************************************************/ |
| |
| /* |
| * The algorithm is based on akito's autohint patch, available here: |
| * |
| * http://www.kde.gr.jp/~akito/patch/freetype2/ |
| * |
| */ |
| |
| #include "aftypes.h" |
| #include "aflatin.h" |
| |
| |
| #ifdef AF_CONFIG_OPTION_CJK |
| |
| #include "afcjk.h" |
| #include "aferrors.h" |
| |
| |
| #ifdef AF_USE_WARPER |
| #include "afwarp.h" |
| #endif |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** C J K G L O B A L M E T R I C S *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| FT_LOCAL_DEF( FT_Error ) |
| af_cjk_metrics_init( AF_LatinMetrics metrics, |
| FT_Face face ) |
| { |
| FT_CharMap oldmap = face->charmap; |
| |
| |
| metrics->units_per_em = face->units_per_EM; |
| |
| /* TODO are there blues? */ |
| |
| if ( FT_Select_Charmap( face, FT_ENCODING_UNICODE ) ) |
| face->charmap = NULL; |
| |
| /* latin's version would suffice */ |
| af_latin_metrics_init_widths( metrics, face, 0x7530 ); |
| |
| FT_Set_Charmap( face, oldmap ); |
| |
| return AF_Err_Ok; |
| } |
| |
| |
| static void |
| af_cjk_metrics_scale_dim( AF_LatinMetrics metrics, |
| AF_Scaler scaler, |
| AF_Dimension dim ) |
| { |
| AF_LatinAxis axis; |
| |
| |
| axis = &metrics->axis[dim]; |
| |
| if ( dim == AF_DIMENSION_HORZ ) |
| { |
| axis->scale = scaler->x_scale; |
| axis->delta = scaler->x_delta; |
| } |
| else |
| { |
| axis->scale = scaler->y_scale; |
| axis->delta = scaler->y_delta; |
| } |
| } |
| |
| |
| FT_LOCAL_DEF( void ) |
| af_cjk_metrics_scale( AF_LatinMetrics metrics, |
| AF_Scaler scaler ) |
| { |
| metrics->root.scaler = *scaler; |
| |
| af_cjk_metrics_scale_dim( metrics, scaler, AF_DIMENSION_HORZ ); |
| af_cjk_metrics_scale_dim( metrics, scaler, AF_DIMENSION_VERT ); |
| } |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** C J K G L Y P H A N A L Y S I S *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| static FT_Error |
| af_cjk_hints_compute_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_Error error; |
| AF_Segment seg; |
| |
| |
| error = af_latin_hints_compute_segments( hints, dim ); |
| if ( error ) |
| return error; |
| |
| /* a segment is round if it doesn't have successive */ |
| /* on-curve points. */ |
| for ( seg = segments; seg < segment_limit; seg++ ) |
| { |
| AF_Point pt = seg->first; |
| AF_Point last = seg->last; |
| AF_Flags f0 = (AF_Flags)(pt->flags & AF_FLAG_CONTROL); |
| AF_Flags f1; |
| |
| |
| seg->flags &= ~AF_EDGE_ROUND; |
| |
| for ( ; pt != last; f0 = f1 ) |
| { |
| pt = pt->next; |
| f1 = (AF_Flags)(pt->flags & AF_FLAG_CONTROL); |
| |
| if ( !f0 && !f1 ) |
| break; |
| |
| if ( pt == last ) |
| seg->flags |= AF_EDGE_ROUND; |
| } |
| } |
| |
| return AF_Err_Ok; |
| } |
| |
| |
| static void |
| af_cjk_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; |
| AF_Direction major_dir = axis->major_dir; |
| AF_Segment seg1, seg2; |
| FT_Pos len_threshold; |
| FT_Pos dist_threshold; |
| |
| |
| len_threshold = AF_LATIN_CONSTANT( hints->metrics, 8 ); |
| |
| dist_threshold = ( dim == AF_DIMENSION_HORZ ) ? hints->x_scale |
| : hints->y_scale; |
| dist_threshold = FT_DivFix( 64 * 3, dist_threshold ); |
| |
| /* now compare each segment to the others */ |
| for ( seg1 = segments; seg1 < segment_limit; seg1++ ) |
| { |
| /* the fake segments are for metrics hinting only */ |
| if ( seg1->first == seg1->last ) |
| continue; |
| |
| if ( seg1->dir != major_dir ) |
| continue; |
| |
| for ( seg2 = segments; seg2 < segment_limit; seg2++ ) |
| if ( seg2 != seg1 && seg1->dir + seg2->dir == 0 ) |
| { |
| FT_Pos dist = seg2->pos - seg1->pos; |
| |
| |
| if ( dist < 0 ) |
| continue; |
| |
| { |
| 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; |
| |
| len = max - min; |
| if ( len >= len_threshold ) |
| { |
| if ( dist * 8 < seg1->score * 9 && |
| ( dist * 8 < seg1->score * 7 || seg1->len < len ) ) |
| { |
| seg1->score = dist; |
| seg1->len = len; |
| seg1->link = seg2; |
| } |
| |
| if ( dist * 8 < seg2->score * 9 && |
| ( dist * 8 < seg2->score * 7 || seg2->len < len ) ) |
| { |
| seg2->score = dist; |
| seg2->len = len; |
| seg2->link = seg1; |
| } |
| } |
| } |
| } |
| } |
| |
| /* |
| * now compute the `serif' segments |
| * |
| * In Hanzi, some strokes are wider on one or both of the ends. |
| * We either identify the stems on the ends as serifs or remove |
| * the linkage, depending on the length of the stems. |
| * |
| */ |
| |
| { |
| AF_Segment link1, link2; |
| |
| |
| for ( seg1 = segments; seg1 < segment_limit; seg1++ ) |
| { |
| link1 = seg1->link; |
| if ( !link1 || link1->link != seg1 || link1->pos <= seg1->pos ) |
| continue; |
| |
| if ( seg1->score >= dist_threshold ) |
| continue; |
| |
| for ( seg2 = segments; seg2 < segment_limit; seg2++ ) |
| { |
| if ( seg2->pos > seg1->pos || seg1 == seg2 ) |
| continue; |
| |
| link2 = seg2->link; |
| if ( !link2 || link2->link != seg2 || link2->pos < link1->pos ) |
| continue; |
| |
| if ( seg1->pos == seg2->pos && link1->pos == link2->pos ) |
| continue; |
| |
| if ( seg2->score <= seg1->score || seg1->score * 4 <= seg2->score ) |
| continue; |
| |
| /* seg2 < seg1 < link1 < link2 */ |
| |
| if ( seg1->len >= seg2->len * 3 ) |
| { |
| AF_Segment seg; |
| |
| |
| for ( seg = segments; seg < segment_limit; seg++ ) |
| { |
| AF_Segment link = seg->link; |
| |
| |
| if ( link == seg2 ) |
| { |
| seg->link = 0; |
| seg->serif = link1; |
| } |
| else if ( link == link2 ) |
| { |
| seg->link = 0; |
| seg->serif = seg1; |
| } |
| } |
| } |
| else |
| { |
| seg1->link = link1->link = 0; |
| |
| break; |
| } |
| } |
| } |
| } |
| |
| for ( seg1 = segments; seg1 < segment_limit; seg1++ ) |
| { |
| seg2 = seg1->link; |
| |
| if ( seg2 ) |
| { |
| seg2->num_linked++; |
| if ( seg2->link != seg1 ) |
| { |
| seg1->link = 0; |
| |
| if ( seg2->score < dist_threshold || seg1->score < seg2->score * 4 ) |
| seg1->serif = seg2->link; |
| else |
| seg2->num_linked--; |
| } |
| } |
| } |
| } |
| |
| |
| static FT_Error |
| af_cjk_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; |
| |
| FT_Fixed scale; |
| FT_Pos edge_distance_threshold; |
| |
| |
| axis->num_edges = 0; |
| |
| scale = ( dim == AF_DIMENSION_HORZ ) ? hints->x_scale |
| : hints->y_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 is then 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 = FT_DivFix( 64 / 4, scale ); |
| else |
| edge_distance_threshold = laxis->edge_distance_threshold; |
| |
| for ( seg = segments; seg < segment_limit; seg++ ) |
| { |
| AF_Edge found = 0; |
| FT_Pos best = 0xFFFFU; |
| FT_Int ee; |
| |
| |
| /* 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; |
| |
| |
| if ( edge->dir != seg->dir ) |
| continue; |
| |
| dist = seg->pos - edge->fpos; |
| if ( dist < 0 ) |
| dist = -dist; |
| |
| if ( dist < edge_distance_threshold && dist < best ) |
| { |
| AF_Segment link = seg->link; |
| |
| |
| /* check whether all linked segments of the candidate edge */ |
| /* can make a single edge. */ |
| if ( link ) |
| { |
| AF_Segment seg1 = edge->first; |
| AF_Segment link1; |
| FT_Pos dist2 = 0; |
| |
| |
| do |
| { |
| link1 = seg1->link; |
| if ( link1 ) |
| { |
| dist2 = AF_SEGMENT_DIST( link, link1 ); |
| if ( dist2 >= edge_distance_threshold ) |
| break; |
| } |
| |
| } while ( ( seg1 = seg1->edge_next ) != edge->first ); |
| |
| if ( dist2 >= edge_distance_threshold ) |
| continue; |
| } |
| |
| best = dist; |
| found = edge; |
| } |
| } |
| |
| 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->opos = edge->pos = FT_MulFix( seg->pos, scale ); |
| seg->edge_next = seg; |
| edge->dir = seg->dir; |
| } |
| 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 now compute each edge's properties according to segments */ |
| /* found on its position. Basically, these are as follows. */ |
| /* */ |
| /* - 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? */ |
| |
| |
| 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 links -- if seg->serif is set, then seg->link must */ |
| /* be ignored */ |
| is_serif = (FT_Bool)( seg->serif && seg->serif->edge != edge ); |
| |
| if ( seg->link || 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 = AF_SEGMENT_DIST( seg, seg2 ); |
| |
| 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; |
| |
| /* 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 = 0; |
| } |
| } |
| |
| Exit: |
| return error; |
| } |
| |
| |
| static FT_Error |
| af_cjk_hints_detect_features( AF_GlyphHints hints, |
| AF_Dimension dim ) |
| { |
| FT_Error error; |
| |
| |
| error = af_cjk_hints_compute_segments( hints, dim ); |
| if ( !error ) |
| { |
| af_cjk_hints_link_segments( hints, dim ); |
| |
| error = af_cjk_hints_compute_edges( hints, dim ); |
| } |
| return error; |
| } |
| |
| |
| FT_LOCAL_DEF( FT_Error ) |
| af_cjk_hints_init( AF_GlyphHints hints, |
| AF_LatinMetrics metrics ) |
| { |
| FT_Render_Mode mode; |
| FT_UInt32 scaler_flags, other_flags; |
| |
| |
| af_glyph_hints_rescale( hints, (AF_ScriptMetrics)metrics ); |
| |
| /* |
| * correct x_scale and y_scale when needed, since they may have |
| * been modified af_cjk_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; |
| |
| #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; |
| |
| scaler_flags |= AF_SCALER_FLAG_NO_ADVANCE; |
| |
| hints->scaler_flags = scaler_flags; |
| hints->other_flags = other_flags; |
| |
| return 0; |
| } |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** C J K 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_cjk_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_cjk_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 ); |
| |
| FT_UNUSED( base_flags ); |
| FT_UNUSED( stem_flags ); |
| |
| |
| if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) ) |
| 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 */ |
| |
| if ( axis->width_count > 0 ) |
| { |
| if ( FT_ABS( dist - axis->widths[0].cur ) < 40 ) |
| { |
| dist = axis->widths[0].cur; |
| if ( dist < 48 ) |
| dist = 48; |
| |
| goto Done_Width; |
| } |
| } |
| |
| if ( dist < 54 ) |
| dist += ( 54 - dist ) / 2 ; |
| else if ( dist < 3 * 64 ) |
| { |
| FT_Pos delta; |
| |
| |
| delta = dist & 63; |
| dist &= -64; |
| |
| if ( delta < 10 ) |
| dist += delta; |
| else if ( delta < 22 ) |
| dist += 10; |
| else if ( delta < 42 ) |
| dist += delta; |
| else if ( delta < 54 ) |
| dist += 54; |
| else |
| dist += delta; |
| } |
| } |
| else |
| { |
| /* strong hinting process: snap the stem width to integer pixels */ |
| |
| dist = af_cjk_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 ) |
| dist = ( dist + 22 ) & ~63; |
| 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_cjk_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_cjk_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; |
| } |
| |
| |
| static void |
| af_cjk_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 ****/ |
| /**** ****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| |
| #define AF_LIGHT_MODE_MAX_HORZ_GAP 9 |
| #define AF_LIGHT_MODE_MAX_VERT_GAP 15 |
| #define AF_LIGHT_MODE_MAX_DELTA_ABS 14 |
| |
| |
| static FT_Pos |
| af_hint_normal_stem( AF_GlyphHints hints, |
| AF_Edge edge, |
| AF_Edge edge2, |
| FT_Pos anchor, |
| AF_Dimension dim ) |
| { |
| FT_Pos org_len, cur_len, org_center; |
| FT_Pos cur_pos1, cur_pos2; |
| FT_Pos d_off1, u_off1, d_off2, u_off2, delta; |
| FT_Pos offset; |
| FT_Pos threshold = 64; |
| |
| |
| if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) ) |
| { |
| if ( ( edge->flags & AF_EDGE_ROUND ) && |
| ( edge2->flags & AF_EDGE_ROUND ) ) |
| { |
| if ( dim == AF_DIMENSION_VERT ) |
| threshold = 64 - AF_LIGHT_MODE_MAX_HORZ_GAP; |
| else |
| threshold = 64 - AF_LIGHT_MODE_MAX_VERT_GAP; |
| } |
| else |
| { |
| if ( dim == AF_DIMENSION_VERT ) |
| threshold = 64 - AF_LIGHT_MODE_MAX_HORZ_GAP / 3; |
| else |
| threshold = 64 - AF_LIGHT_MODE_MAX_VERT_GAP / 3; |
| } |
| } |
| |
| org_len = edge2->opos - edge->opos; |
| cur_len = af_cjk_compute_stem_width( hints, dim, org_len, |
| (AF_Edge_Flags)edge->flags, |
| (AF_Edge_Flags)edge2->flags ); |
| |
| org_center = ( edge->opos + edge2->opos ) / 2 + anchor; |
| cur_pos1 = org_center - cur_len / 2; |
| cur_pos2 = cur_pos1 + cur_len; |
| d_off1 = cur_pos1 - FT_PIX_FLOOR( cur_pos1 ); |
| d_off2 = cur_pos2 - FT_PIX_FLOOR( cur_pos2 ); |
| u_off1 = 64 - d_off1; |
| u_off2 = 64 - d_off2; |
| delta = 0; |
| |
| |
| if ( d_off1 == 0 || d_off2 == 0 ) |
| goto Exit; |
| |
| if ( cur_len <= threshold ) |
| { |
| if ( d_off2 < cur_len ) |
| { |
| if ( u_off1 <= d_off2 ) |
| delta = u_off1; |
| else |
| delta = -d_off2; |
| } |
| |
| goto Exit; |
| } |
| |
| if ( threshold < 64 ) |
| { |
| if ( d_off1 >= threshold || u_off1 >= threshold || |
| d_off2 >= threshold || u_off2 >= threshold ) |
| goto Exit; |
| } |
| |
| offset = cur_len % 64; |
| |
| if ( offset < 32 ) |
| { |
| if ( u_off1 <= offset || d_off2 <= offset ) |
| goto Exit; |
| } |
| else |
| offset = 64 - threshold; |
| |
| d_off1 = threshold - u_off1; |
| u_off1 = u_off1 - offset; |
| u_off2 = threshold - d_off2; |
| d_off2 = d_off2 - offset; |
| |
| if ( d_off1 <= u_off1 ) |
| u_off1 = -d_off1; |
| |
| if ( d_off2 <= u_off2 ) |
| u_off2 = -d_off2; |
| |
| if ( FT_ABS( u_off1 ) <= FT_ABS( u_off2 ) ) |
| delta = u_off1; |
| else |
| delta = u_off2; |
| |
| Exit: |
| |
| #if 1 |
| if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) ) |
| { |
| if ( delta > AF_LIGHT_MODE_MAX_DELTA_ABS ) |
| delta = AF_LIGHT_MODE_MAX_DELTA_ABS; |
| else if ( delta < -AF_LIGHT_MODE_MAX_DELTA_ABS ) |
| delta = -AF_LIGHT_MODE_MAX_DELTA_ABS; |
| } |
| #endif |
| |
| cur_pos1 += delta; |
| |
| if ( edge->opos < edge2->opos ) |
| { |
| edge->pos = cur_pos1; |
| edge2->pos = cur_pos1 + cur_len; |
| } |
| else |
| { |
| edge->pos = cur_pos1 + cur_len; |
| edge2->pos = cur_pos1; |
| } |
| |
| return delta; |
| } |
| |
| |
| static void |
| af_cjk_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_Pos delta = 0; |
| FT_Int skipped = 0; |
| |
| |
| /* now we align all stem edges. */ |
| 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 ) |
| { |
| skipped++; |
| continue; |
| } |
| |
| /* now align the stem */ |
| |
| if ( edge2 < edge ) |
| { |
| af_cjk_align_linked_edge( hints, dim, edge2, edge ); |
| edge->flags |= AF_EDGE_DONE; |
| continue; |
| } |
| |
| if ( dim != AF_DIMENSION_VERT && !anchor ) |
| { |
| |
| #if 0 |
| if ( fixedpitch ) |
| { |
| AF_Edge left = edge; |
| AF_Edge right = edge_limit - 1; |
| AF_EdgeRec left1, left2, right1, right2; |
| FT_Pos target, center1, center2; |
| FT_Pos delta1, delta2, d1, d2; |
| |
| |
| while ( right > left && !right->link ) |
| right--; |
| |
| left1 = *left; |
| left2 = *left->link; |
| right1 = *right->link; |
| right2 = *right; |
| |
| delta = ( ( ( hinter->pp2.x + 32 ) & -64 ) - hinter->pp2.x ) / 2; |
| target = left->opos + ( right->opos - left->opos ) / 2 + delta - 16; |
| |
| delta1 = delta; |
| delta1 += af_hint_normal_stem( hints, left, left->link, |
| delta1, 0 ); |
| |
| if ( left->link != right ) |
| af_hint_normal_stem( hints, right->link, right, delta1, 0 ); |
| |
| center1 = left->pos + ( right->pos - left->pos ) / 2; |
| |
| if ( center1 >= target ) |
| delta2 = delta - 32; |
| else |
| delta2 = delta + 32; |
| |
| delta2 += af_hint_normal_stem( hints, &left1, &left2, delta2, 0 ); |
| |
| if ( delta1 != delta2 ) |
| { |
| if ( left->link != right ) |
| af_hint_normal_stem( hints, &right1, &right2, delta2, 0 ); |
| |
| center2 = left1.pos + ( right2.pos - left1.pos ) / 2; |
| |
| d1 = center1 - target; |
| d2 = center2 - target; |
| |
| if ( FT_ABS( d2 ) < FT_ABS( d1 ) ) |
| { |
| left->pos = left1.pos; |
| left->link->pos = left2.pos; |
| |
| if ( left->link != right ) |
| { |
| right->link->pos = right1.pos; |
| right->pos = right2.pos; |
| } |
| |
| delta1 = delta2; |
| } |
| } |
| |
| delta = delta1; |
| right->link->flags |= AF_EDGE_DONE; |
| right->flags |= AF_EDGE_DONE; |
| } |
| else |
| |
| #endif /* 0 */ |
| |
| delta = af_hint_normal_stem( hints, edge, edge2, 0, |
| AF_DIMENSION_HORZ ); |
| } |
| else |
| af_hint_normal_stem( hints, edge, edge2, delta, dim ); |
| |
| #if 0 |
| printf( "stem (%d,%d) adjusted (%.1f,%.1f)\n", |
| edge - edges, edge2 - edges, |
| ( edge->pos - edge->opos ) / 64.0, |
| ( edge2->pos - edge2->opos ) / 64.0 ); |
| #endif |
| |
| anchor = edge; |
| edge->flags |= AF_EDGE_DONE; |
| edge2->flags |= AF_EDGE_DONE; |
| } |
| |
| /* 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; |
| |
| |
| 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 ( edge1->link == edge1 + 1 && |
| edge2->link == edge2 + 1 && |
| edge3->link == edge3 + 1 && 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 ( !skipped ) |
| return; |
| |
| /* |
| * now hint the remaining edges (serifs and single) in order |
| * to complete our processing |
| */ |
| for ( edge = edges; edge < edge_limit; edge++ ) |
| { |
| if ( edge->flags & AF_EDGE_DONE ) |
| continue; |
| |
| if ( edge->serif ) |
| { |
| af_cjk_align_serif_edge( hints, edge->serif, edge ); |
| edge->flags |= AF_EDGE_DONE; |
| skipped--; |
| } |
| } |
| |
| if ( !skipped ) |
| return; |
| |
| for ( edge = edges; edge < edge_limit; edge++ ) |
| { |
| AF_Edge before, after; |
| |
| |
| if ( edge->flags & AF_EDGE_DONE ) |
| continue; |
| |
| before = after = edge; |
| |
| while ( --before >= edges ) |
| if ( before->flags & AF_EDGE_DONE ) |
| break; |
| |
| while ( ++after < edge_limit ) |
| if ( after->flags & AF_EDGE_DONE ) |
| break; |
| |
| if ( before >= edges || after < edge_limit ) |
| { |
| if ( before < edges ) |
| af_cjk_align_serif_edge( hints, after, edge ); |
| else if ( after >= edge_limit ) |
| af_cjk_align_serif_edge( hints, before, edge ); |
| else |
| { |
| if ( after->fpos == before->fpos ) |
| edge->pos = before->pos; |
| else |
| edge->pos = before->pos + |
| FT_MulDiv( edge->fpos - before->fpos, |
| after->pos - before->pos, |
| after->fpos - before->fpos ); |
| } |
| } |
| } |
| } |
| |
| |
| static void |
| af_cjk_align_edge_points( 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; |
| AF_Edge edge; |
| FT_Bool snapping; |
| |
| |
| snapping = FT_BOOL( ( dim == AF_DIMENSION_HORZ && |
| AF_LATIN_HINTS_DO_HORZ_SNAP( hints ) ) || |
| ( dim == AF_DIMENSION_VERT && |
| AF_LATIN_HINTS_DO_VERT_SNAP( hints ) ) ); |
| |
| for ( edge = edges; edge < edge_limit; edge++ ) |
| { |
| /* move the points of each segment */ |
| /* in each edge to the edge's position */ |
| AF_Segment seg = edge->first; |
| |
| |
| if ( snapping ) |
| { |
| do |
| { |
| AF_Point point = seg->first; |
| |
| |
| for (;;) |
| { |
| if ( dim == AF_DIMENSION_HORZ ) |
| { |
| point->x = edge->pos; |
| point->flags |= AF_FLAG_TOUCH_X; |
| } |
| else |
| { |
| point->y = edge->pos; |
| point->flags |= AF_FLAG_TOUCH_Y; |
| } |
| |
| if ( point == seg->last ) |
| break; |
| |
| point = point->next; |
| } |
| |
| seg = seg->edge_next; |
| |
| } while ( seg != edge->first ); |
| } |
| else |
| { |
| FT_Pos delta = edge->pos - edge->opos; |
| |
| |
| do |
| { |
| AF_Point point = seg->first; |
| |
| |
| for (;;) |
| { |
| if ( dim == AF_DIMENSION_HORZ ) |
| { |
| point->x += delta; |
| point->flags |= AF_FLAG_TOUCH_X; |
| } |
| else |
| { |
| point->y += delta; |
| point->flags |= AF_FLAG_TOUCH_Y; |
| } |
| |
| if ( point == seg->last ) |
| break; |
| |
| point = point->next; |
| } |
| |
| seg = seg->edge_next; |
| |
| } while ( seg != edge->first ); |
| } |
| } |
| } |
| |
| |
| FT_LOCAL_DEF( FT_Error ) |
| af_cjk_hints_apply( AF_GlyphHints hints, |
| FT_Outline* outline, |
| AF_LatinMetrics metrics ) |
| { |
| FT_Error error; |
| int dim; |
| |
| FT_UNUSED( metrics ); |
| |
| |
| error = af_glyph_hints_reload( hints, outline, 0 ); |
| if ( error ) |
| goto Exit; |
| |
| /* analyze glyph outline */ |
| if ( AF_HINTS_DO_HORIZONTAL( hints ) ) |
| { |
| error = af_cjk_hints_detect_features( hints, AF_DIMENSION_HORZ ); |
| if ( error ) |
| goto Exit; |
| } |
| |
| if ( AF_HINTS_DO_VERTICAL( hints ) ) |
| { |
| error = af_cjk_hints_detect_features( hints, AF_DIMENSION_VERT ); |
| if ( error ) |
| goto Exit; |
| } |
| |
| /* grid-fit the outline */ |
| for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ ) |
| { |
| if ( ( dim == AF_DIMENSION_HORZ && AF_HINTS_DO_HORIZONTAL( hints ) ) || |
| ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_VERTICAL( hints ) ) ) |
| { |
| |
| #ifdef AF_USE_WARPER |
| if ( dim == AF_DIMENSION_HORZ && |
| metrics->root.scaler.render_mode == FT_RENDER_MODE_NORMAL ) |
| { |
| 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 /* AF_USE_WARPER */ |
| |
| af_cjk_hint_edges( hints, (AF_Dimension)dim ); |
| af_cjk_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 ); |
| } |
| } |
| |
| #if 0 |
| af_glyph_hints_dump_points( hints ); |
| af_glyph_hints_dump_segments( hints ); |
| af_glyph_hints_dump_edges( hints ); |
| #endif |
| |
| af_glyph_hints_save( hints, outline ); |
| |
| Exit: |
| return error; |
| } |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** C J K S C R I P T C L A S S *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| |
| static const AF_Script_UniRangeRec af_cjk_uniranges[] = |
| { |
| #if 0 |
| { 0x0100UL, 0xFFFFUL }, /* why this? */ |
| #endif |
| { 0x2E80UL, 0x2EFFUL }, /* CJK Radicals Supplement */ |
| { 0x2F00UL, 0x2FDFUL }, /* Kangxi Radicals */ |
| { 0x3000UL, 0x303FUL }, /* CJK Symbols and Punctuation */ |
| { 0x3040UL, 0x309FUL }, /* Hiragana */ |
| { 0x30A0UL, 0x30FFUL }, /* Katakana */ |
| { 0x3100UL, 0x312FUL }, /* Bopomofo */ |
| { 0x3130UL, 0x318FUL }, /* Hangul Compatibility Jamo */ |
| { 0x31A0UL, 0x31BFUL }, /* Bopomofo Extended */ |
| { 0x31C0UL, 0x31EFUL }, /* CJK Strokes */ |
| { 0x31F0UL, 0x31FFUL }, /* Katakana Phonetic Extensions */ |
| { 0x3200UL, 0x32FFUL }, /* Enclosed CJK Letters and Months */ |
| { 0x3300UL, 0x33FFUL }, /* CJK Compatibility */ |
| { 0x3400UL, 0x4DBFUL }, /* CJK Unified Ideographs Extension A */ |
| { 0x4DC0UL, 0x4DFFUL }, /* Yijing Hexagram Symbols */ |
| { 0x4E00UL, 0x9FFFUL }, /* CJK Unified Ideographs */ |
| { 0xF900UL, 0xFAFFUL }, /* CJK Compatibility Ideographs */ |
| { 0xFE30UL, 0xFE4FUL }, /* CJK Compatibility Forms */ |
| { 0xFF00UL, 0xFFEFUL }, /* Halfwidth and Fullwidth Forms */ |
| { 0x20000UL, 0x2A6DFUL }, /* CJK Unified Ideographs Extension B */ |
| { 0x2F800UL, 0x2FA1FUL }, /* CJK Compatibility Ideographs Supplement */ |
| { 0UL, 0UL } |
| }; |
| |
| |
| AF_DEFINE_SCRIPT_CLASS(af_cjk_script_class, |
| AF_SCRIPT_CJK, |
| af_cjk_uniranges, |
| |
| sizeof( AF_LatinMetricsRec ), |
| |
| (AF_Script_InitMetricsFunc) af_cjk_metrics_init, |
| (AF_Script_ScaleMetricsFunc)af_cjk_metrics_scale, |
| (AF_Script_DoneMetricsFunc) NULL, |
| |
| (AF_Script_InitHintsFunc) af_cjk_hints_init, |
| (AF_Script_ApplyHintsFunc) af_cjk_hints_apply |
| ) |
| |
| #else /* !AF_CONFIG_OPTION_CJK */ |
| |
| static const AF_Script_UniRangeRec af_cjk_uniranges[] = |
| { |
| { 0, 0 } |
| }; |
| |
| |
| AF_DEFINE_SCRIPT_CLASS(af_cjk_script_class, |
| AF_SCRIPT_CJK, |
| af_cjk_uniranges, |
| |
| sizeof( AF_LatinMetricsRec ), |
| |
| (AF_Script_InitMetricsFunc) NULL, |
| (AF_Script_ScaleMetricsFunc)NULL, |
| (AF_Script_DoneMetricsFunc) NULL, |
| |
| (AF_Script_InitHintsFunc) NULL, |
| (AF_Script_ApplyHintsFunc) NULL |
| ) |
| |
| #endif /* !AF_CONFIG_OPTION_CJK */ |
| |
| |
| /* END */ |