--- a/misc/libfreetype/src/autofit/aflatin.c Tue Jul 16 11:14:27 2013 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,2306 +0,0 @@
-/***************************************************************************/
-/* */
-/* aflatin.c */
-/* */
-/* Auto-fitter hinting routines for latin script (body). */
-/* */
-/* Copyright 2003-2011 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 <ft2build.h>
-#include FT_ADVANCES_H
-#include FT_INTERNAL_DEBUG_H
-
-#include "aflatin.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_aflatin
-
-
- /*************************************************************************/
- /*************************************************************************/
- /***** *****/
- /***** L A T I N G L O B A L M E T R I C S *****/
- /***** *****/
- /*************************************************************************/
- /*************************************************************************/
-
-
- /* Find segments and links, compute all stem widths, and initialize */
- /* standard width and height for the glyph with given charcode. */
-
- 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 = 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_ScriptMetrics)dummy );
-
- error = af_glyph_hints_reload( hints, &face->glyph->outline );
- if ( error )
- goto Exit;
-
- for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
- {
- AF_LatinAxis axis = &metrics->axis[dim];
- AF_AxisHints axhints = &hints->axis[dim];
- AF_Segment seg, limit, link;
- FT_UInt num_widths = 0;
-
-
- error = af_latin_hints_compute_segments( hints,
- (AF_Dimension)dim );
- if ( error )
- goto Exit;
-
- 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 af_latin_blue_chars[AF_LATIN_MAX_BLUES]
- [AF_LATIN_MAX_TEST_CHARACTERS + 1] =
- {
- "THEZOCQS",
- "HEZLOCUS",
- "fijkdbh",
- "xzroesc",
- "xzroesc",
- "pqgjy"
- };
-
-
- /* Find all blue zones. Flat segments give the reference points, */
- /* round segments the overshoot positions. */
-
- 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 finding its top-most or */
- /* bottom-most points (depending on `AF_IS_TOP_BLUE') */
-
- FT_TRACE5(( "blue zones computation\n" ));
- FT_TRACE5(( "------------------------------------------------\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;
-
-
- FT_TRACE5(( "blue %3d: ", bb ));
-
- num_flats = 0;
- num_rounds = 0;
-
- for ( ; p < limit && *p; p++ )
- {
- FT_UInt glyph_index;
- FT_Pos best_y; /* same as points.y */
- FT_Int best_point, best_first, best_last;
- FT_Vector* points;
- FT_Bool round = 0;
-
-
- FT_TRACE5(( "'%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;
- }
- }
- FT_TRACE5(( "%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 );
-
- FT_TRACE5(( "%c ", round ? 'r' : 'f' ));
- }
-
- if ( round )
- rounds[num_rounds++] = best_y;
- else
- flats[num_flats++] = best_y;
- }
-
- FT_TRACE5(( "\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
- */
- FT_TRACE5(( "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_ref =
- *blue_shoot = ( shoot + ref ) / 2;
- }
-
- blue->flags = 0;
- if ( AF_LATIN_IS_TOP_BLUE( bb ) )
- blue->flags |= AF_LATIN_BLUE_TOP;
-
- /*
- * The following flag 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;
-
- FT_TRACE5(( "-- ref = %ld, shoot = %ld\n", *blue_ref, *blue_shoot ));
- }
-
- return;
- }
-
-
- /* Check whether all ASCII digits have the same advance width. */
-
- FT_LOCAL_DEF( void )
- af_latin_metrics_check_digits( AF_LatinMetrics 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_UInt glyph_index;
-
-
- glyph_index = FT_Get_Char_Index( face, i );
- 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_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 );
- af_latin_metrics_check_digits( metrics, face );
- }
-
- FT_Set_Charmap( face, oldmap );
- return AF_Err_Ok;
- }
-
-
- /* Adjust scaling value, then scale and shift widths */
- /* and blue zones (if applicable) for given dimension. */
-
- 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 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;
- }
- }
- }
- }
-
-
- /* Scale global values in both directions. */
-
- 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 *****/
- /***** *****/
- /*************************************************************************/
- /*************************************************************************/
-
-
- /* Walk over all contours and compute its segments. */
-
- 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;
- }
-
-
- /* Link segments to form stems and serifs. */
-
- 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;
-
- /* search for stems having opposite directions, */
- /* with seg1 to the `left' of seg2 */
- for ( seg2 = segments; seg2 < segment_limit; seg2++ )
- {
- FT_Pos pos1 = seg1->pos;
- FT_Pos pos2 = seg2->pos;
-
-
- if ( seg1->dir + seg2->dir == 0 && pos2 > pos1 )
- {
- /* compute distance between the two segments */
- FT_Pos dist = pos2 - pos1;
- 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;
-
- /* compute maximum coordinate difference of the two segments */
- len = max - min;
- if ( len >= len_threshold )
- {
- /* small coordinate differences cause a higher score, and */
- /* segments with a greater distance cause a higher score also */
- score = dist + len_score / len;
-
- /* and we search for the smallest score */
- /* of the sum of the two values */
- if ( score < seg1->score )
- {
- seg1->score = score;
- seg1->link = seg2;
- }
-
- if ( score < seg2->score )
- {
- seg2->score = score;
- seg2->link = seg1;
- }
- }
- }
- }
- }
-
- /* now compute the `serif' segments, cf. explanations in `afhints.h' */
- for ( seg1 = segments; seg1 < segment_limit; seg1++ )
- {
- seg2 = seg1->link;
-
- if ( seg2 )
- {
- if ( seg2->link != seg1 )
- {
- seg1->link = 0;
- seg1->serif = seg2->link;
- }
- }
- }
- }
-
-
- /* Link segments to edges, using feature analysis for selection. */
-
- 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 pixel in length
- * to avoid many problems with serif fonts. We compute the
- * corresponding threshold in font units.
- */
- if ( dim == AF_DIMENSION_HORZ )
- segment_length_threshold = FT_DivFix( 64, hints->y_scale );
- else
- segment_length_threshold = 0;
-
- /*********************************************************************/
- /* */
- /* We begin by generating a sorted table of edges for the current */
- /* direction. To do so, we simply scan each segment and try to find */
- /* an edge in our table that corresponds to its position. */
- /* */
- /* If no edge is found, we create and insert a new edge in the */
- /* sorted table. Otherwise, we simply add the segment to the edge's */
- /* list which gets processed in the second step to compute the */
- /* edge's properties. */
- /* */
- /* Note that the table of edges is sorted along the segment/edge */
- /* position. */
- /* */
- /*********************************************************************/
-
- /* assure that edge distance threshold is at least 0.25px */
- edge_distance_threshold = FT_MulFix( laxis->edge_distance_threshold,
- scale );
- if ( edge_distance_threshold > 64 / 4 )
- edge_distance_threshold = 64 / 4;
-
- edge_distance_threshold = FT_DivFix( edge_distance_threshold,
- scale );
-
- for ( seg = segments; seg < segment_limit; seg++ )
- {
- AF_Edge found = NULL;
- FT_Int ee;
-
-
- 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->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 will now compute each edge's properties according to */
- /* the segments found on its position. Basically, these are */
- /* */
- /* - the edge's main direction */
- /* - stem edge, serif edge or both (which defaults to stem then) */
- /* - rounded edge, straight or both (which defaults to straight) */
- /* - link for edge */
- /* */
- /*********************************************************************/
-
- /* first of all, set the `edge' field in each segment -- this is */
- /* required in order to compute edge links */
-
- /*
- * Note that removing this loop and setting the `edge' field of each
- * segment directly in the code above slows down execution speed for
- * some reasons on platforms like the Sun.
- */
- {
- AF_Edge edges = axis->edges;
- AF_Edge edge_limit = edges + axis->num_edges;
- AF_Edge edge;
-
-
- for ( edge = edges; edge < edge_limit; edge++ )
- {
- seg = edge->first;
- if ( seg )
- do
- {
- seg->edge = edge;
- seg = seg->edge_next;
-
- } while ( seg != edge->first );
- }
-
- /* now compute each edge properties */
- for ( edge = edges; edge < edge_limit; edge++ )
- {
- FT_Int is_round = 0; /* does it contain round segments? */
- FT_Int is_straight = 0; /* does it contain straight segments? */
-#if 0
- FT_Pos ups = 0; /* number of upwards segments */
- FT_Pos downs = 0; /* number of downwards segments */
-#endif
-
-
- seg = edge->first;
-
- do
- {
- FT_Bool is_serif;
-
-
- /* check for roundness of segment */
- if ( seg->flags & AF_EDGE_ROUND )
- is_round++;
- else
- is_straight++;
-
-#if 0
- /* check for segment direction */
- if ( seg->dir == up_dir )
- ups += seg->max_coord - seg->min_coord;
- else
- downs += seg->max_coord - seg->min_coord;
-#endif
-
- /* check for links -- if seg->serif is set, then seg->link must */
- /* be ignored */
- is_serif = (FT_Bool)( seg->serif &&
- seg->serif->edge &&
- seg->serif->edge != edge );
-
- if ( ( seg->link && seg->link->edge != 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
-
- /* 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;
- }
-
-
- /* Detect segments and edges for given dimension. */
-
- 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;
- }
-
-
- /* Compute all edges which lie within blue zones. */
-
- 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 */
- /* (the value 40 is heuristic) */
- best_dist = FT_MulFix( metrics->units_per_em / 40, scale );
-
- /* assure a minimum distance of 0.5px */
- 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 large) */
- 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 and check whether */
- /* the edge is rounded, and whether 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 )
- {
- 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;
- }
- }
-
-
- /* Initalize hinting engine. */
-
- 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 by `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_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;
-
- /*
- * 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 AF_Err_Ok;
- }
-
-
- /*************************************************************************/
- /*************************************************************************/
- /***** *****/
- /***** 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, ignoring very thin ones. */
- /* There is a lot of voodoo in this function; changing the hard-coded */
- /* parameters influence the whole hinting process. */
-
- 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 */
- 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_Pos 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;
-
- FT_TRACE5(( "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 ));
- }
-
-
- /* Shift the coordinates of the `serif' edge by the same amount */
- /* as the corresponding `base' edge has been moved already. */
-
- 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 ****/
- /**** ****/
- /*************************************************************************/
- /*************************************************************************/
- /*************************************************************************/
-
-
- /* The main grid-fitting routine. */
-
- 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_PtrDist n_edges;
- AF_Edge edge;
- AF_Edge anchor = NULL;
- 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;
-
- FT_TRACE5(( "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 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 )
- {
- FT_TRACE5(( "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 );
-
- /* some voodoo to specially round edges for small stem widths */
- if ( cur_len <= 64 )
- {
- u_off = 32;
- 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 );
-
- FT_TRACE5(( "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 = 32;
- 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;
-
- FT_TRACE5(( "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;
-
- FT_TRACE5(( "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 )
- {
- FT_TRACE5(( "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 );
- FT_TRACE5(( "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 )
- {
- FT_TRACE5(( "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 );
-
- FT_TRACE5(( "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 );
-
- FT_TRACE5(( "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;
- }
- }
- }
-
-
- /* Apply the complete hinting algorithm to a latin glyph. */
-
- 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 );
- 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_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_CONFIG_OPTION_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, (AF_Dimension)dim,
- &scale, &delta );
- af_glyph_hints_scale_dim( hints, (AF_Dimension)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[] =
- {
- AF_UNIRANGE_REC( 0x0020UL, 0x007FUL ), /* Basic Latin (no control chars) */
- AF_UNIRANGE_REC( 0x00A0UL, 0x00FFUL ), /* Latin-1 Supplement (no control chars) */
- AF_UNIRANGE_REC( 0x0100UL, 0x017FUL ), /* Latin Extended-A */
- AF_UNIRANGE_REC( 0x0180UL, 0x024FUL ), /* Latin Extended-B */
- AF_UNIRANGE_REC( 0x0250UL, 0x02AFUL ), /* IPA Extensions */
- AF_UNIRANGE_REC( 0x02B0UL, 0x02FFUL ), /* Spacing Modifier Letters */
- AF_UNIRANGE_REC( 0x0300UL, 0x036FUL ), /* Combining Diacritical Marks */
- AF_UNIRANGE_REC( 0x0370UL, 0x03FFUL ), /* Greek and Coptic */
- AF_UNIRANGE_REC( 0x0400UL, 0x04FFUL ), /* Cyrillic */
- AF_UNIRANGE_REC( 0x0500UL, 0x052FUL ), /* Cyrillic Supplement */
- AF_UNIRANGE_REC( 0x1D00UL, 0x1D7FUL ), /* Phonetic Extensions */
- AF_UNIRANGE_REC( 0x1D80UL, 0x1DBFUL ), /* Phonetic Extensions Supplement */
- AF_UNIRANGE_REC( 0x1DC0UL, 0x1DFFUL ), /* Combining Diacritical Marks Supplement */
- AF_UNIRANGE_REC( 0x1E00UL, 0x1EFFUL ), /* Latin Extended Additional */
- AF_UNIRANGE_REC( 0x1F00UL, 0x1FFFUL ), /* Greek Extended */
- AF_UNIRANGE_REC( 0x2000UL, 0x206FUL ), /* General Punctuation */
- AF_UNIRANGE_REC( 0x2070UL, 0x209FUL ), /* Superscripts and Subscripts */
- AF_UNIRANGE_REC( 0x20A0UL, 0x20CFUL ), /* Currency Symbols */
- AF_UNIRANGE_REC( 0x2150UL, 0x218FUL ), /* Number Forms */
- AF_UNIRANGE_REC( 0x2460UL, 0x24FFUL ), /* Enclosed Alphanumerics */
- AF_UNIRANGE_REC( 0x2C60UL, 0x2C7FUL ), /* Latin Extended-C */
- AF_UNIRANGE_REC( 0x2DE0UL, 0x2DFFUL ), /* Cyrillic Extended-A */
- AF_UNIRANGE_REC( 0xA640UL, 0xA69FUL ), /* Cyrillic Extended-B */
- AF_UNIRANGE_REC( 0xA720UL, 0xA7FFUL ), /* Latin Extended-D */
- AF_UNIRANGE_REC( 0xFB00UL, 0xFB06UL ), /* Alphab. Present. Forms (Latin Ligs) */
- AF_UNIRANGE_REC( 0x1D400UL, 0x1D7FFUL ), /* Mathematical Alphanumeric Symbols */
- AF_UNIRANGE_REC( 0UL, 0UL )
- };
-
-
- AF_DEFINE_SCRIPT_CLASS(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 */