/***************************************************************************/ | |
/* */ | |
/* afcjk.c */ | |
/* */ | |
/* Auto-fitter hinting routines for CJK writing system (body). */ | |
/* */ | |
/* Copyright 2006-2015 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 <ft2build.h> | |
#include FT_ADVANCES_H | |
#include FT_INTERNAL_DEBUG_H | |
#include "afglobal.h" | |
#include "afpic.h" | |
#include "aflatin.h" | |
#ifdef AF_CONFIG_OPTION_CJK | |
#undef AF_CONFIG_OPTION_CJK_BLUE_HANI_VERT | |
#include "afcjk.h" | |
#include "aferrors.h" | |
#ifdef AF_CONFIG_OPTION_USE_WARPER | |
#include "afwarp.h" | |
#endif | |
/*************************************************************************/ | |
/* */ | |
/* The macro FT_COMPONENT is used in trace mode. It is an implicit */ | |
/* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */ | |
/* messages during execution. */ | |
/* */ | |
#undef FT_COMPONENT | |
#define FT_COMPONENT trace_afcjk | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/***** *****/ | |
/***** C J K G L O B A L M E T R I C S *****/ | |
/***** *****/ | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/* Basically the Latin version with AF_CJKMetrics */ | |
/* to replace AF_LatinMetrics. */ | |
FT_LOCAL_DEF( void ) | |
af_cjk_metrics_init_widths( AF_CJKMetrics metrics, | |
FT_Face face ) | |
{ | |
/* scan the array of segments in each direction */ | |
AF_GlyphHintsRec hints[1]; | |
FT_TRACE5(( "\n" | |
"cjk standard widths computation (style `%s')\n" | |
"===================================================\n" | |
"\n", | |
af_style_names[metrics->root.style_class->style] )); | |
af_glyph_hints_init( hints, face->memory ); | |
metrics->axis[AF_DIMENSION_HORZ].width_count = 0; | |
metrics->axis[AF_DIMENSION_VERT].width_count = 0; | |
{ | |
FT_Error error; | |
FT_ULong glyph_index; | |
FT_Long y_offset; | |
int dim; | |
AF_CJKMetricsRec dummy[1]; | |
AF_Scaler scaler = &dummy->root.scaler; | |
#ifdef FT_CONFIG_OPTION_PIC | |
AF_FaceGlobals globals = metrics->root.globals; | |
#endif | |
AF_StyleClass style_class = metrics->root.style_class; | |
AF_ScriptClass script_class = AF_SCRIPT_CLASSES_GET | |
[style_class->script]; | |
FT_UInt32 standard_char; | |
standard_char = script_class->standard_char1; | |
af_get_char_index( &metrics->root, | |
standard_char, | |
&glyph_index, | |
&y_offset ); | |
if ( !glyph_index ) | |
{ | |
if ( script_class->standard_char2 ) | |
{ | |
standard_char = script_class->standard_char2; | |
af_get_char_index( &metrics->root, | |
standard_char, | |
&glyph_index, | |
&y_offset ); | |
if ( !glyph_index ) | |
{ | |
if ( script_class->standard_char3 ) | |
{ | |
standard_char = script_class->standard_char3; | |
af_get_char_index( &metrics->root, | |
standard_char, | |
&glyph_index, | |
&y_offset ); | |
if ( !glyph_index ) | |
goto Exit; | |
} | |
else | |
goto Exit; | |
} | |
} | |
else | |
goto Exit; | |
} | |
FT_TRACE5(( "standard character: U+%04lX (glyph index %d)\n", | |
standard_char, glyph_index )); | |
error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE ); | |
if ( error || face->glyph->outline.n_points <= 0 ) | |
goto Exit; | |
FT_ZERO( dummy ); | |
dummy->units_per_em = metrics->units_per_em; | |
scaler->x_scale = 0x10000L; | |
scaler->y_scale = 0x10000L; | |
scaler->x_delta = 0; | |
scaler->y_delta = 0; | |
scaler->face = face; | |
scaler->render_mode = FT_RENDER_MODE_NORMAL; | |
scaler->flags = 0; | |
af_glyph_hints_rescale( hints, (AF_StyleMetrics)dummy ); | |
error = af_glyph_hints_reload( hints, &face->glyph->outline ); | |
if ( error ) | |
goto Exit; | |
for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ ) | |
{ | |
AF_CJKAxis 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, | |
0, | |
NULL, | |
(AF_Dimension)dim ); | |
seg = axhints->segments; | |
limit = seg + axhints->num_segments; | |
for ( ; seg < limit; seg++ ) | |
{ | |
link = seg->link; | |
/* we only consider stem segments there! */ | |
if ( link && link->link == seg && link > seg ) | |
{ | |
FT_Pos dist; | |
dist = seg->pos - link->pos; | |
if ( dist < 0 ) | |
dist = -dist; | |
if ( num_widths < AF_CJK_MAX_WIDTHS ) | |
axis->widths[num_widths++].org = dist; | |
} | |
} | |
/* this also replaces multiple almost identical stem widths */ | |
/* with a single one (the value 100 is heuristic) */ | |
af_sort_and_quantize_widths( &num_widths, axis->widths, | |
dummy->units_per_em / 100 ); | |
axis->width_count = num_widths; | |
} | |
Exit: | |
for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ ) | |
{ | |
AF_CJKAxis axis = &metrics->axis[dim]; | |
FT_Pos stdw; | |
stdw = ( axis->width_count > 0 ) ? axis->widths[0].org | |
: AF_LATIN_CONSTANT( metrics, 50 ); | |
/* let's try 20% of the smallest width */ | |
axis->edge_distance_threshold = stdw / 5; | |
axis->standard_width = stdw; | |
axis->extra_light = 0; | |
#ifdef FT_DEBUG_LEVEL_TRACE | |
{ | |
FT_UInt i; | |
FT_TRACE5(( "%s widths:\n", | |
dim == AF_DIMENSION_VERT ? "horizontal" | |
: "vertical" )); | |
FT_TRACE5(( " %d (standard)", axis->standard_width )); | |
for ( i = 1; i < axis->width_count; i++ ) | |
FT_TRACE5(( " %d", axis->widths[i].org )); | |
FT_TRACE5(( "\n" )); | |
} | |
#endif | |
} | |
} | |
FT_TRACE5(( "\n" )); | |
af_glyph_hints_done( hints ); | |
} | |
/* Find all blue zones. */ | |
static void | |
af_cjk_metrics_init_blues( AF_CJKMetrics metrics, | |
FT_Face face ) | |
{ | |
FT_Pos fills[AF_BLUE_STRING_MAX_LEN]; | |
FT_Pos flats[AF_BLUE_STRING_MAX_LEN]; | |
FT_UInt num_fills; | |
FT_UInt num_flats; | |
FT_Bool fill; | |
AF_CJKBlue blue; | |
FT_Error error; | |
AF_CJKAxis axis; | |
FT_Outline outline; | |
AF_StyleClass sc = metrics->root.style_class; | |
AF_Blue_Stringset bss = sc->blue_stringset; | |
const AF_Blue_StringRec* bs = &af_blue_stringsets[bss]; | |
/* we walk over the blue character strings as specified in the */ | |
/* style's entry in the `af_blue_stringset' array, computing its */ | |
/* extremum points (depending on the string properties) */ | |
FT_TRACE5(( "cjk blue zones computation\n" | |
"==========================\n" | |
"\n" )); | |
for ( ; bs->string != AF_BLUE_STRING_MAX; bs++ ) | |
{ | |
const char* p = &af_blue_strings[bs->string]; | |
FT_Pos* blue_ref; | |
FT_Pos* blue_shoot; | |
if ( AF_CJK_IS_HORIZ_BLUE( bs ) ) | |
axis = &metrics->axis[AF_DIMENSION_HORZ]; | |
else | |
axis = &metrics->axis[AF_DIMENSION_VERT]; | |
#ifdef FT_DEBUG_LEVEL_TRACE | |
{ | |
FT_String* cjk_blue_name[4] = | |
{ | |
(FT_String*)"bottom", /* -- , -- */ | |
(FT_String*)"top", /* -- , TOP */ | |
(FT_String*)"left", /* HORIZ, -- */ | |
(FT_String*)"right" /* HORIZ, TOP */ | |
}; | |
FT_TRACE5(( "blue zone %d (%s):\n", | |
axis->blue_count, | |
cjk_blue_name[AF_CJK_IS_HORIZ_BLUE( bs ) | | |
AF_CJK_IS_TOP_BLUE( bs ) ] )); | |
} | |
#endif /* FT_DEBUG_LEVEL_TRACE */ | |
num_fills = 0; | |
num_flats = 0; | |
fill = 1; /* start with characters that define fill values */ | |
FT_TRACE5(( " [overshoot values]\n" )); | |
while ( *p ) | |
{ | |
FT_ULong ch; | |
FT_ULong glyph_index; | |
FT_Long y_offset; | |
FT_Pos best_pos; /* same as points.y or points.x, resp. */ | |
FT_Int best_point; | |
FT_Vector* points; | |
GET_UTF8_CHAR( ch, p ); | |
/* switch to characters that define flat values */ | |
if ( ch == '|' ) | |
{ | |
fill = 0; | |
FT_TRACE5(( " [reference values]\n" )); | |
continue; | |
} | |
/* load the character in the face -- skip unknown or empty ones */ | |
af_get_char_index( &metrics->root, ch, &glyph_index, &y_offset ); | |
if ( glyph_index == 0 ) | |
{ | |
FT_TRACE5(( " U+%04lX unavailable\n", ch )); | |
continue; | |
} | |
error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE ); | |
outline = face->glyph->outline; | |
if ( error || outline.n_points <= 0 ) | |
{ | |
FT_TRACE5(( " U+%04lX contains no outlines\n", ch )); | |
continue; | |
} | |
/* now compute min or max point indices and coordinates */ | |
points = outline.points; | |
best_point = -1; | |
best_pos = 0; /* make compiler happy */ | |
{ | |
FT_Int nn; | |
FT_Int first = 0; | |
FT_Int last = -1; | |
for ( nn = 0; nn < outline.n_contours; first = last + 1, nn++ ) | |
{ | |
FT_Int pp; | |
last = 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_CJK_IS_HORIZ_BLUE( bs ) ) | |
{ | |
if ( AF_CJK_IS_RIGHT_BLUE( bs ) ) | |
{ | |
for ( pp = first; pp <= last; pp++ ) | |
if ( best_point < 0 || points[pp].x > best_pos ) | |
{ | |
best_point = pp; | |
best_pos = points[pp].x; | |
} | |
} | |
else | |
{ | |
for ( pp = first; pp <= last; pp++ ) | |
if ( best_point < 0 || points[pp].x < best_pos ) | |
{ | |
best_point = pp; | |
best_pos = points[pp].x; | |
} | |
} | |
} | |
else | |
{ | |
if ( AF_CJK_IS_TOP_BLUE( bs ) ) | |
{ | |
for ( pp = first; pp <= last; pp++ ) | |
if ( best_point < 0 || points[pp].y > best_pos ) | |
{ | |
best_point = pp; | |
best_pos = points[pp].y; | |
} | |
} | |
else | |
{ | |
for ( pp = first; pp <= last; pp++ ) | |
if ( best_point < 0 || points[pp].y < best_pos ) | |
{ | |
best_point = pp; | |
best_pos = points[pp].y; | |
} | |
} | |
} | |
} | |
FT_TRACE5(( " U+%04lX: best_pos = %5ld\n", ch, best_pos )); | |
} | |
if ( fill ) | |
fills[num_fills++] = best_pos; | |
else | |
flats[num_flats++] = best_pos; | |
} | |
if ( num_flats == 0 && num_fills == 0 ) | |
{ | |
/* | |
* we couldn't find a single glyph to compute this blue zone, | |
* we will simply ignore it then | |
*/ | |
FT_TRACE5(( " empty\n" )); | |
continue; | |
} | |
/* we have computed the contents of the `fill' 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_fills, fills ); | |
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 = fills[num_fills / 2]; | |
} | |
else if ( num_fills == 0 ) | |
{ | |
*blue_ref = | |
*blue_shoot = flats[num_flats / 2]; | |
} | |
else | |
{ | |
*blue_ref = fills[num_fills / 2]; | |
*blue_shoot = flats[num_flats / 2]; | |
} | |
/* make sure blue_ref >= blue_shoot for top/right or */ | |
/* vice versa for bottom/left */ | |
if ( *blue_shoot != *blue_ref ) | |
{ | |
FT_Pos ref = *blue_ref; | |
FT_Pos shoot = *blue_shoot; | |
FT_Bool under_ref = FT_BOOL( shoot < ref ); | |
/* AF_CJK_IS_TOP_BLUE covers `right' and `top' */ | |
if ( AF_CJK_IS_TOP_BLUE( bs ) ^ under_ref ) | |
{ | |
*blue_ref = | |
*blue_shoot = ( shoot + ref ) / 2; | |
FT_TRACE5(( " [reference smaller than overshoot," | |
" taking mean value]\n" )); | |
} | |
} | |
blue->flags = 0; | |
if ( AF_CJK_IS_TOP_BLUE( bs ) ) | |
blue->flags |= AF_CJK_BLUE_TOP; | |
FT_TRACE5(( " -> reference = %ld\n" | |
" overshoot = %ld\n", | |
*blue_ref, *blue_shoot )); | |
} | |
FT_TRACE5(( "\n" )); | |
return; | |
} | |
/* Basically the Latin version with type AF_CJKMetrics for metrics. */ | |
FT_LOCAL_DEF( void ) | |
af_cjk_metrics_check_digits( AF_CJKMetrics metrics, | |
FT_Face face ) | |
{ | |
FT_UInt i; | |
FT_Bool started = 0, same_width = 1; | |
FT_Fixed advance, old_advance = 0; | |
/* digit `0' is 0x30 in all supported charmaps */ | |
for ( i = 0x30; i <= 0x39; i++ ) | |
{ | |
FT_ULong glyph_index; | |
FT_Long y_offset; | |
af_get_char_index( &metrics->root, i, &glyph_index, &y_offset ); | |
if ( glyph_index == 0 ) | |
continue; | |
if ( FT_Get_Advance( face, glyph_index, | |
FT_LOAD_NO_SCALE | | |
FT_LOAD_NO_HINTING | | |
FT_LOAD_IGNORE_TRANSFORM, | |
&advance ) ) | |
continue; | |
if ( started ) | |
{ | |
if ( advance != old_advance ) | |
{ | |
same_width = 0; | |
break; | |
} | |
} | |
else | |
{ | |
old_advance = advance; | |
started = 1; | |
} | |
} | |
metrics->root.digits_have_same_width = same_width; | |
} | |
/* Initialize global metrics. */ | |
FT_LOCAL_DEF( FT_Error ) | |
af_cjk_metrics_init( AF_CJKMetrics metrics, | |
FT_Face face ) | |
{ | |
FT_CharMap oldmap = face->charmap; | |
metrics->units_per_em = face->units_per_EM; | |
if ( !FT_Select_Charmap( face, FT_ENCODING_UNICODE ) ) | |
{ | |
af_cjk_metrics_init_widths( metrics, face ); | |
af_cjk_metrics_init_blues( metrics, face ); | |
af_cjk_metrics_check_digits( metrics, face ); | |
} | |
FT_Set_Charmap( face, oldmap ); | |
return FT_Err_Ok; | |
} | |
/* Adjust scaling value, then scale and shift widths */ | |
/* and blue zones (if applicable) for given dimension. */ | |
static void | |
af_cjk_metrics_scale_dim( AF_CJKMetrics metrics, | |
AF_Scaler scaler, | |
AF_Dimension dim ) | |
{ | |
FT_Fixed scale; | |
FT_Pos delta; | |
AF_CJKAxis 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; | |
axis->scale = scale; | |
axis->delta = delta; | |
/* scale the blue zones */ | |
for ( nn = 0; nn < axis->blue_count; nn++ ) | |
{ | |
AF_CJKBlue 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_CJK_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; | |
blue->ref.fit = FT_PIX_ROUND( blue->ref.cur ); | |
/* shoot is under shoot for cjk */ | |
delta1 = FT_DivFix( blue->ref.fit, scale ) - blue->shoot.org; | |
delta2 = delta1; | |
if ( delta1 < 0 ) | |
delta2 = -delta2; | |
delta2 = FT_MulFix( delta2, scale ); | |
FT_TRACE5(( "delta: %d", delta1 )); | |
if ( delta2 < 32 ) | |
delta2 = 0; | |
#if 0 | |
else if ( delta2 < 64 ) | |
delta2 = 32 + ( ( ( delta2 - 32 ) + 16 ) & ~31 ); | |
#endif | |
else | |
delta2 = FT_PIX_ROUND( delta2 ); | |
FT_TRACE5(( "/%d\n", delta2 )); | |
if ( delta1 < 0 ) | |
delta2 = -delta2; | |
blue->shoot.fit = blue->ref.fit - delta2; | |
FT_TRACE5(( ">> active cjk blue zone %c%d[%ld/%ld]:\n" | |
" ref: cur=%.2f fit=%.2f\n" | |
" shoot: cur=%.2f fit=%.2f\n", | |
( dim == AF_DIMENSION_HORZ ) ? 'H' : 'V', | |
nn, blue->ref.org, blue->shoot.org, | |
blue->ref.cur / 64.0, blue->ref.fit / 64.0, | |
blue->shoot.cur / 64.0, blue->shoot.fit / 64.0 )); | |
blue->flags |= AF_CJK_BLUE_ACTIVE; | |
} | |
} | |
} | |
/* Scale global values in both directions. */ | |
FT_LOCAL_DEF( void ) | |
af_cjk_metrics_scale( AF_CJKMetrics metrics, | |
AF_Scaler scaler ) | |
{ | |
/* we copy the whole structure since the x and y scaling values */ | |
/* are not modified, contrary to e.g. the `latin' auto-hinter */ | |
metrics->root.scaler = *scaler; | |
af_cjk_metrics_scale_dim( metrics, scaler, AF_DIMENSION_HORZ ); | |
af_cjk_metrics_scale_dim( metrics, scaler, AF_DIMENSION_VERT ); | |
} | |
/* Extract standard_width from writing system/script specific */ | |
/* metrics class. */ | |
FT_LOCAL_DEF( void ) | |
af_cjk_get_standard_widths( AF_CJKMetrics metrics, | |
FT_Pos* stdHW, | |
FT_Pos* stdVW ) | |
{ | |
if ( stdHW ) | |
*stdHW = metrics->axis[AF_DIMENSION_VERT].standard_width; | |
if ( stdVW ) | |
*stdVW = metrics->axis[AF_DIMENSION_HORZ].standard_width; | |
} | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/***** *****/ | |
/***** C J K G L Y P H A N A L Y S I S *****/ | |
/***** *****/ | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/* Walk over all contours and compute its segments. */ | |
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; | |
FT_UInt f0 = pt->flags & AF_FLAG_CONTROL; | |
FT_UInt f1; | |
seg->flags &= ~AF_EDGE_ROUND; | |
for ( ; pt != last; f0 = f1 ) | |
{ | |
pt = pt->next; | |
f1 = pt->flags & AF_FLAG_CONTROL; | |
if ( !f0 && !f1 ) | |
break; | |
if ( pt == last ) | |
seg->flags |= AF_EDGE_ROUND; | |
} | |
} | |
return FT_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++ ) | |
{ | |
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 = NULL; | |
seg->serif = link1; | |
} | |
else if ( link == link2 ) | |
{ | |
seg->link = NULL; | |
seg->serif = seg1; | |
} | |
} | |
} | |
else | |
{ | |
seg1->link = link1->link = NULL; | |
break; | |
} | |
} | |
} | |
} | |
for ( seg1 = segments; seg1 < segment_limit; seg1++ ) | |
{ | |
seg2 = seg1->link; | |
if ( seg2 ) | |
{ | |
seg2->num_linked++; | |
if ( seg2->link != seg1 ) | |
{ | |
seg1->link = NULL; | |
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 = FT_Err_Ok; | |
FT_Memory memory = hints->memory; | |
AF_CJKAxis laxis = &((AF_CJKMetrics)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 = NULL; | |
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; | |
FT_Pos dist2 = 0; | |
do | |
{ | |
AF_Segment 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->dir = seg->dir; | |
edge->fpos = seg->pos; | |
edge->opos = FT_MulFix( seg->pos, scale ); | |
edge->pos = edge->opos; | |
seg->edge_next = seg; | |
} | |
else | |
{ | |
/* if an edge was found, simply add the segment to the edge's */ | |
/* list */ | |
seg->edge_next = found->first; | |
found->last->edge_next = seg; | |
found->last = seg; | |
} | |
} | |
/******************************************************************/ | |
/* */ | |
/* Good, we now compute each edge's properties according to the */ | |
/* segments found on its position. Basically, these are */ | |
/* */ | |
/* - the edge's main direction */ | |
/* - stem edge, serif edge or both (which defaults to stem then) */ | |
/* - rounded edge, straight or both (which defaults to straight) */ | |
/* - link for edge */ | |
/* */ | |
/******************************************************************/ | |
/* first of all, set the `edge' field in each segment -- this is */ | |
/* required in order to compute edge links */ | |
/* | |
* Note that removing this loop and setting the `edge' field of each | |
* segment directly in the code above slows down execution speed for | |
* some reasons on platforms like the Sun. | |
*/ | |
{ | |
AF_Edge edges = axis->edges; | |
AF_Edge edge_limit = edges + axis->num_edges; | |
AF_Edge edge; | |
for ( edge = edges; edge < edge_limit; edge++ ) | |
{ | |
seg = edge->first; | |
if ( seg ) | |
do | |
{ | |
seg->edge = edge; | |
seg = seg->edge_next; | |
} while ( seg != edge->first ); | |
} | |
/* now compute each edge properties */ | |
for ( edge = edges; edge < edge_limit; edge++ ) | |
{ | |
FT_Int is_round = 0; /* does it contain round segments? */ | |
FT_Int is_straight = 0; /* does it contain straight segments? */ | |
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 = NULL; | |
} | |
} | |
Exit: | |
return error; | |
} | |
/* Detect segments and edges for given dimension. */ | |
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; | |
} | |
/* Compute all edges which lie within blue zones. */ | |
static void | |
af_cjk_hints_compute_blue_edges( AF_GlyphHints hints, | |
AF_CJKMetrics metrics, | |
AF_Dimension dim ) | |
{ | |
AF_AxisHints axis = &hints->axis[dim]; | |
AF_Edge edge = axis->edges; | |
AF_Edge edge_limit = edge + axis->num_edges; | |
AF_CJKAxis cjk = &metrics->axis[dim]; | |
FT_Fixed scale = cjk->scale; | |
FT_Pos best_dist0; /* initial threshold */ | |
/* compute the initial threshold as a fraction of the EM size */ | |
best_dist0 = FT_MulFix( metrics->units_per_em / 40, scale ); | |
if ( best_dist0 > 64 / 2 ) /* maximum 1/2 pixel */ | |
best_dist0 = 64 / 2; | |
/* compute which blue zones are active, i.e. have their scaled */ | |
/* size < 3/4 pixels */ | |
/* If the distant between an edge and a blue zone is shorter than */ | |
/* best_dist0, set the blue zone for the edge. Then search for */ | |
/* the blue zone with the smallest best_dist to the edge. */ | |
for ( ; edge < edge_limit; edge++ ) | |
{ | |
FT_UInt bb; | |
AF_Width best_blue = NULL; | |
FT_Pos best_dist = best_dist0; | |
for ( bb = 0; bb < cjk->blue_count; bb++ ) | |
{ | |
AF_CJKBlue blue = cjk->blues + bb; | |
FT_Bool is_top_right_blue, is_major_dir; | |
/* skip inactive blue zones (i.e., those that are too small) */ | |
if ( !( blue->flags & AF_CJK_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_right_blue = | |
(FT_Byte)( ( blue->flags & AF_CJK_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_right_blue ^ is_major_dir ) | |
{ | |
FT_Pos dist; | |
AF_Width compare; | |
/* Compare the edge to the closest blue zone type */ | |
if ( FT_ABS( edge->fpos - blue->ref.org ) > | |
FT_ABS( edge->fpos - blue->shoot.org ) ) | |
compare = &blue->shoot; | |
else | |
compare = &blue->ref; | |
dist = edge->fpos - compare->org; | |
if ( dist < 0 ) | |
dist = -dist; | |
dist = FT_MulFix( dist, scale ); | |
if ( dist < best_dist ) | |
{ | |
best_dist = dist; | |
best_blue = compare; | |
} | |
} | |
} | |
if ( best_blue ) | |
edge->blue_edge = best_blue; | |
} | |
} | |
/* Initalize hinting engine. */ | |
FT_LOCAL_DEF( FT_Error ) | |
af_cjk_hints_init( AF_GlyphHints hints, | |
AF_CJKMetrics metrics ) | |
{ | |
FT_Render_Mode mode; | |
FT_UInt32 scaler_flags, other_flags; | |
af_glyph_hints_rescale( hints, (AF_StyleMetrics)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; | |
#if 0 /* AF_CONFIG_OPTION_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; | |
#ifdef AF_CONFIG_OPTION_USE_WARPER | |
/* get (global) warper flag */ | |
if ( !metrics->root.globals->module->warping ) | |
scaler_flags |= AF_SCALER_FLAG_NO_WARPER; | |
#endif | |
hints->scaler_flags = scaler_flags; | |
hints->other_flags = other_flags; | |
return FT_Err_Ok; | |
} | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/***** *****/ | |
/***** 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_UInt count, | |
FT_Pos width ) | |
{ | |
FT_UInt 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. */ | |
/* There is a lot of voodoo in this function; changing the hard-coded */ | |
/* parameters influence the whole hinting process. */ | |
static FT_Pos | |
af_cjk_compute_stem_width( AF_GlyphHints hints, | |
AF_Dimension dim, | |
FT_Pos width, | |
FT_UInt base_flags, | |
FT_UInt stem_flags ) | |
{ | |
AF_CJKMetrics metrics = (AF_CJKMetrics)hints->metrics; | |
AF_CJKAxis axis = &metrics->axis[dim]; | |
FT_Pos dist = width; | |
FT_Int sign = 0; | |
FT_Bool vertical = FT_BOOL( 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, | |
base_edge->flags, | |
stem_edge->flags ); | |
stem_edge->pos = base_edge->pos + fitted_width; | |
FT_TRACE5(( " CJKLINK: edge %d @%d (opos=%.2f) linked to %.2f," | |
" dist was %.2f, now %.2f\n", | |
stem_edge - hints->axis[dim].edges, stem_edge->fpos, | |
stem_edge->opos / 64.0, stem_edge->pos / 64.0, | |
dist / 64.0, fitted_width / 64.0 )); | |
} | |
/* Shift the coordinates of the `serif' edge by the same amount */ | |
/* as the corresponding `base' edge has been moved already. */ | |
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, | |
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 & 63; | |
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; | |
} | |
/* The main grid-fitting routine. */ | |
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_PtrDist n_edges; | |
AF_Edge edge; | |
AF_Edge anchor = NULL; | |
FT_Pos delta = 0; | |
FT_Int skipped = 0; | |
FT_Bool has_last_stem = FALSE; | |
FT_Pos last_stem_pos = 0; | |
#ifdef FT_DEBUG_LEVEL_TRACE | |
FT_UInt num_actions = 0; | |
#endif | |
FT_TRACE5(( "cjk %s edge hinting (style `%s')\n", | |
dim == AF_DIMENSION_VERT ? "horizontal" : "vertical", | |
af_style_names[hints->metrics->style_class->style] )); | |
/* we begin by aligning all stems relative to the blue zone */ | |
if ( 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; | |
#ifdef FT_DEBUG_LEVEL_TRACE | |
FT_TRACE5(( " CJKBLUE: edge %d @%d (opos=%.2f) snapped to %.2f," | |
" was %.2f\n", | |
edge1 - edges, edge1->fpos, edge1->opos / 64.0, | |
blue->fit / 64.0, edge1->pos / 64.0 )); | |
num_actions++; | |
#endif | |
edge1->pos = blue->fit; | |
edge1->flags |= AF_EDGE_DONE; | |
if ( edge2 && !edge2->blue_edge ) | |
{ | |
af_cjk_align_linked_edge( hints, dim, edge1, edge2 ); | |
edge2->flags |= AF_EDGE_DONE; | |
#ifdef FT_DEBUG_LEVEL_TRACE | |
num_actions++; | |
#endif | |
} | |
if ( !anchor ) | |
anchor = edge; | |
} | |
} | |
/* 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; | |
} | |
/* Some CJK characters have so many stems that | |
* the hinter is likely to merge two adjacent ones. | |
* To solve this problem, if either edge of a stem | |
* is too close to the previous one, we avoid | |
* aligning the two edges, but rather interpolate | |
* their locations at the end of this function in | |
* order to preserve the space between the stems. | |
*/ | |
if ( has_last_stem && | |
( edge->pos < last_stem_pos + 64 || | |
edge2->pos < last_stem_pos + 64 ) ) | |
{ | |
skipped++; | |
continue; | |
} | |
/* now align the stem */ | |
/* this should not happen, but it's better to be safe */ | |
if ( edge2->blue_edge ) | |
{ | |
FT_TRACE5(( "ASSERTION FAILED for edge %d\n", edge2-edges )); | |
af_cjk_align_linked_edge( hints, dim, edge2, edge ); | |
edge->flags |= AF_EDGE_DONE; | |
#ifdef FT_DEBUG_LEVEL_TRACE | |
num_actions++; | |
#endif | |
continue; | |
} | |
if ( edge2 < edge ) | |
{ | |
af_cjk_align_linked_edge( hints, dim, edge2, edge ); | |
edge->flags |= AF_EDGE_DONE; | |
#ifdef FT_DEBUG_LEVEL_TRACE | |
num_actions++; | |
#endif | |
/* We rarely reaches here it seems; | |
* usually the two edges belonging | |
* to one stem are marked as DONE together | |
*/ | |
has_last_stem = TRUE; | |
last_stem_pos = edge->pos; | |
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; | |
has_last_stem = TRUE; | |
last_stem_pos = edge2->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; | |
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 ) | |
goto Exit; | |
/* | |
* 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 ) | |
goto Exit; | |
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 ); | |
} | |
} | |
} | |
Exit: | |
#ifdef FT_DEBUG_LEVEL_TRACE | |
if ( !num_actions ) | |
FT_TRACE5(( " (none)\n" )); | |
FT_TRACE5(( "\n" )); | |
#endif | |
return; | |
} | |
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 ); | |
} | |
} | |
} | |
/* Apply the complete hinting algorithm to a CJK glyph. */ | |
FT_LOCAL_DEF( FT_Error ) | |
af_cjk_hints_apply( FT_UInt glyph_index, | |
AF_GlyphHints hints, | |
FT_Outline* outline, | |
AF_CJKMetrics metrics ) | |
{ | |
FT_Error error; | |
int dim; | |
FT_UNUSED( metrics ); | |
FT_UNUSED( glyph_index ); | |
error = af_glyph_hints_reload( hints, outline ); | |
if ( error ) | |
goto Exit; | |
/* analyze glyph outline */ | |
#ifdef AF_CONFIG_OPTION_USE_WARPER | |
if ( ( metrics->root.scaler.render_mode == FT_RENDER_MODE_LIGHT && | |
AF_HINTS_DO_WARP( hints ) ) || | |
AF_HINTS_DO_HORIZONTAL( hints ) ) | |
#else | |
if ( AF_HINTS_DO_HORIZONTAL( hints ) ) | |
#endif | |
{ | |
error = af_cjk_hints_detect_features( hints, AF_DIMENSION_HORZ ); | |
if ( error ) | |
goto Exit; | |
af_cjk_hints_compute_blue_edges( hints, metrics, AF_DIMENSION_HORZ ); | |
} | |
if ( AF_HINTS_DO_VERTICAL( hints ) ) | |
{ | |
error = af_cjk_hints_detect_features( hints, AF_DIMENSION_VERT ); | |
if ( error ) | |
goto Exit; | |
af_cjk_hints_compute_blue_edges( hints, metrics, AF_DIMENSION_VERT ); | |
} | |
/* 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_CONFIG_OPTION_USE_WARPER | |
if ( dim == AF_DIMENSION_HORZ && | |
metrics->root.scaler.render_mode == FT_RENDER_MODE_LIGHT && | |
AF_HINTS_DO_WARP( hints ) ) | |
{ | |
AF_WarperRec warper; | |
FT_Fixed scale; | |
FT_Pos delta; | |
af_warper_compute( &warper, hints, (AF_Dimension)dim, | |
&scale, &delta ); | |
af_glyph_hints_scale_dim( hints, (AF_Dimension)dim, | |
scale, delta ); | |
continue; | |
} | |
#endif /* AF_CONFIG_OPTION_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 ); | |
} | |
} | |
af_glyph_hints_save( hints, outline ); | |
Exit: | |
return error; | |
} | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/***** *****/ | |
/***** C J K S C R I P T C L A S S *****/ | |
/***** *****/ | |
/*************************************************************************/ | |
/*************************************************************************/ | |
AF_DEFINE_WRITING_SYSTEM_CLASS( | |
af_cjk_writing_system_class, | |
AF_WRITING_SYSTEM_CJK, | |
sizeof ( AF_CJKMetricsRec ), | |
(AF_WritingSystem_InitMetricsFunc) af_cjk_metrics_init, | |
(AF_WritingSystem_ScaleMetricsFunc)af_cjk_metrics_scale, | |
(AF_WritingSystem_DoneMetricsFunc) NULL, | |
(AF_WritingSystem_GetStdWidthsFunc)af_cjk_get_standard_widths, | |
(AF_WritingSystem_InitHintsFunc) af_cjk_hints_init, | |
(AF_WritingSystem_ApplyHintsFunc) af_cjk_hints_apply | |
) | |
#else /* !AF_CONFIG_OPTION_CJK */ | |
AF_DEFINE_WRITING_SYSTEM_CLASS( | |
af_cjk_writing_system_class, | |
AF_WRITING_SYSTEM_CJK, | |
sizeof ( AF_CJKMetricsRec ), | |
(AF_WritingSystem_InitMetricsFunc) NULL, | |
(AF_WritingSystem_ScaleMetricsFunc)NULL, | |
(AF_WritingSystem_DoneMetricsFunc) NULL, | |
(AF_WritingSystem_GetStdWidthsFunc)NULL, | |
(AF_WritingSystem_InitHintsFunc) NULL, | |
(AF_WritingSystem_ApplyHintsFunc) NULL | |
) | |
#endif /* !AF_CONFIG_OPTION_CJK */ | |
/* END */ |