diff options
Diffstat (limited to 'libfreetype/pshalgo3.c')
| -rw-r--r-- | libfreetype/pshalgo3.c | 1757 |
1 files changed, 1757 insertions, 0 deletions
diff --git a/libfreetype/pshalgo3.c b/libfreetype/pshalgo3.c new file mode 100644 index 00000000..4ee01715 --- /dev/null +++ b/libfreetype/pshalgo3.c @@ -0,0 +1,1757 @@ +/***************************************************************************/ +/* */ +/* pshalgo3.c */ +/* */ +/* PostScript hinting algorithm 3 (body). */ +/* */ +/* Copyright 2001, 2002 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_INTERNAL_OBJECTS_H +#include FT_INTERNAL_DEBUG_H +#include "pshalgo3.h" + + +#undef FT_COMPONENT +#define FT_COMPONENT trace_pshalgo2 + + +#ifdef DEBUG_HINTER + PSH3_Hint_Table ps3_debug_hint_table = 0; + PSH3_HintFunc ps3_debug_hint_func = 0; + PSH3_Glyph ps3_debug_glyph = 0; +#endif + + +#define COMPUTE_INFLEXS /* compute inflection points to optimize "S" and others */ +#define STRONGER /* slightly increase the contrast of smooth hinting */ + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** BASIC HINTS RECORDINGS *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + + /* return true iff two stem hints overlap */ + static FT_Int + psh3_hint_overlap( PSH3_Hint hint1, + PSH3_Hint hint2 ) + { + return ( hint1->org_pos + hint1->org_len >= hint2->org_pos && + hint2->org_pos + hint2->org_len >= hint1->org_pos ); + } + + + /* destroy hints table */ + static void + psh3_hint_table_done( PSH3_Hint_Table table, + FT_Memory memory ) + { + FT_FREE( table->zones ); + table->num_zones = 0; + table->zone = 0; + + FT_FREE( table->sort ); + FT_FREE( table->hints ); + table->num_hints = 0; + table->max_hints = 0; + table->sort_global = 0; + } + + + /* deactivate all hints in a table */ + static void + psh3_hint_table_deactivate( PSH3_Hint_Table table ) + { + FT_UInt count = table->max_hints; + PSH3_Hint hint = table->hints; + + + for ( ; count > 0; count--, hint++ ) + { + psh3_hint_deactivate( hint ); + hint->order = -1; + } + } + + + /* internal function used to record a new hint */ + static void + psh3_hint_table_record( PSH3_Hint_Table table, + FT_UInt idx ) + { + PSH3_Hint hint = table->hints + idx; + + + if ( idx >= table->max_hints ) + { + FT_ERROR(( "psh3_hint_table_record: invalid hint index %d\n", idx )); + return; + } + + /* ignore active hints */ + if ( psh3_hint_is_active( hint ) ) + return; + + psh3_hint_activate( hint ); + + /* now scan the current active hint set in order to determine */ + /* if we are overlapping with another segment */ + { + PSH3_Hint* sorted = table->sort_global; + FT_UInt count = table->num_hints; + PSH3_Hint hint2; + + + hint->parent = 0; + for ( ; count > 0; count--, sorted++ ) + { + hint2 = sorted[0]; + + if ( psh3_hint_overlap( hint, hint2 ) ) + { + hint->parent = hint2; + break; + } + } + } + + if ( table->num_hints < table->max_hints ) + table->sort_global[table->num_hints++] = hint; + else + FT_ERROR(( "psh3_hint_table_record: too many sorted hints! BUG!\n" )); + } + + + static void + psh3_hint_table_record_mask( PSH3_Hint_Table table, + PS_Mask hint_mask ) + { + FT_Int mask = 0, val = 0; + FT_Byte* cursor = hint_mask->bytes; + FT_UInt idx, limit; + + + limit = hint_mask->num_bits; + + for ( idx = 0; idx < limit; idx++ ) + { + if ( mask == 0 ) + { + val = *cursor++; + mask = 0x80; + } + + if ( val & mask ) + psh3_hint_table_record( table, idx ); + + mask >>= 1; + } + } + + + /* create hints table */ + static FT_Error + psh3_hint_table_init( PSH3_Hint_Table table, + PS_Hint_Table hints, + PS_Mask_Table hint_masks, + PS_Mask_Table counter_masks, + FT_Memory memory ) + { + FT_UInt count = hints->num_hints; + FT_Error error; + + FT_UNUSED( counter_masks ); + + + /* allocate our tables */ + if ( FT_NEW_ARRAY( table->sort, 2 * count ) || + FT_NEW_ARRAY( table->hints, count ) || + FT_NEW_ARRAY( table->zones, 2 * count + 1 ) ) + goto Exit; + + table->max_hints = count; + table->sort_global = table->sort + count; + table->num_hints = 0; + table->num_zones = 0; + table->zone = 0; + + /* now, initialize the "hints" array */ + { + PSH3_Hint write = table->hints; + PS_Hint read = hints->hints; + + + for ( ; count > 0; count--, write++, read++ ) + { + write->org_pos = read->pos; + write->org_len = read->len; + write->flags = read->flags; + } + } + + /* we now need to determine the initial "parent" stems; first */ + /* activate the hints that are given by the initial hint masks */ + if ( hint_masks ) + { + FT_UInt Count = hint_masks->num_masks; + PS_Mask Mask = hint_masks->masks; + + + table->hint_masks = hint_masks; + + for ( ; Count > 0; Count--, Mask++ ) + psh3_hint_table_record_mask( table, Mask ); + } + + /* now, do a linear parse in case some hints were left alone */ + if ( table->num_hints != table->max_hints ) + { + FT_UInt Index, Count; + + + FT_ERROR(( "psh3_hint_table_init: missing/incorrect hint masks!\n" )); + Count = table->max_hints; + for ( Index = 0; Index < Count; Index++ ) + psh3_hint_table_record( table, Index ); + } + + Exit: + return error; + } + + + static void + psh3_hint_table_activate_mask( PSH3_Hint_Table table, + PS_Mask hint_mask ) + { + FT_Int mask = 0, val = 0; + FT_Byte* cursor = hint_mask->bytes; + FT_UInt idx, limit, count; + + + limit = hint_mask->num_bits; + count = 0; + + psh3_hint_table_deactivate( table ); + + for ( idx = 0; idx < limit; idx++ ) + { + if ( mask == 0 ) + { + val = *cursor++; + mask = 0x80; + } + + if ( val & mask ) + { + PSH3_Hint hint = &table->hints[idx]; + + + if ( !psh3_hint_is_active( hint ) ) + { + FT_UInt count2; + +#if 0 + PSH3_Hint* sort = table->sort; + PSH3_Hint hint2; + + + for ( count2 = count; count2 > 0; count2--, sort++ ) + { + hint2 = sort[0]; + if ( psh3_hint_overlap( hint, hint2 ) ) + FT_ERROR(( "psh3_hint_table_activate_mask:" + " found overlapping hints\n" )) + } +#else + count2 = 0; +#endif + + if ( count2 == 0 ) + { + psh3_hint_activate( hint ); + if ( count < table->max_hints ) + table->sort[count++] = hint; + else + FT_ERROR(( "psh3_hint_tableactivate_mask:" + " too many active hints\n" )); + } + } + } + + mask >>= 1; + } + table->num_hints = count; + + /* now, sort the hints; they are guaranteed to not overlap */ + /* so we can compare their "org_pos" field directly */ + { + FT_Int i1, i2; + PSH3_Hint hint1, hint2; + PSH3_Hint* sort = table->sort; + + + /* a simple bubble sort will do, since in 99% of cases, the hints */ + /* will be already sorted -- and the sort will be linear */ + for ( i1 = 1; i1 < (FT_Int)count; i1++ ) + { + hint1 = sort[i1]; + for ( i2 = i1 - 1; i2 >= 0; i2-- ) + { + hint2 = sort[i2]; + + if ( hint2->org_pos < hint1->org_pos ) + break; + + sort[i2 + 1] = hint2; + sort[i2] = hint1; + } + } + } + } + + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** HINTS GRID-FITTING AND OPTIMIZATION *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + + static FT_Pos + psh3_dimension_quantize_len( PSH_Dimension dim, + FT_Pos len, + FT_Bool do_snapping ) + { + if ( len <= 64 ) + len = 64; + else + { + FT_Pos delta = len - dim->stdw.widths[0].cur; + + + if ( delta < 0 ) + delta = -delta; + + if ( delta < 40 ) + { + len = dim->stdw.widths[0].cur; + if ( len < 48 ) + len = 48; + } + + if ( len < 3 * 64 ) + { + delta = ( len & 63 ); + len &= -64; + + if ( delta < 10 ) + len += delta; + + else if ( delta < 32 ) + len += 10; + + else if ( delta < 54 ) + len += 54; + + else + len += delta; + } + else + len = ( len + 32 ) & -64; + } + + if ( do_snapping ) + len = ( len + 32 ) & -64; + + return len; + } + + +#ifdef DEBUG_HINTER + + static void + ps3_simple_scale( PSH3_Hint_Table table, + FT_Fixed scale, + FT_Fixed delta, + FT_Int dimension ) + { + PSH3_Hint hint; + FT_UInt count; + + + for ( count = 0; count < table->max_hints; count++ ) + { + hint = table->hints + count; + + hint->cur_pos = FT_MulFix( hint->org_pos, scale ) + delta; + hint->cur_len = FT_MulFix( hint->org_len, scale ); + + if ( ps3_debug_hint_func ) + ps3_debug_hint_func( hint, dimension ); + } + } + +#endif /* DEBUG_HINTER */ + + + static FT_Fixed + psh3_hint_snap_stem_side_delta( FT_Fixed pos, + FT_Fixed len ) + { + FT_Fixed delta1 = ( ( pos + 32 ) & -64 ) - pos; + FT_Fixed delta2 = ( ( pos + len + 32 ) & -64 ) - pos - len; + + + if ( ABS( delta1 ) <= ABS( delta2 ) ) + return delta1; + else + return delta2; + } + + + static void + psh3_hint_align( PSH3_Hint hint, + PSH_Globals globals, + FT_Int dimension, + PSH3_Glyph glyph ) + { + PSH_Dimension dim = &globals->dimension[dimension]; + FT_Fixed scale = dim->scale_mult; + FT_Fixed delta = dim->scale_delta; + + + if ( !psh3_hint_is_fitted( hint ) ) + { + FT_Pos pos = FT_MulFix( hint->org_pos, scale ) + delta; + FT_Pos len = FT_MulFix( hint->org_len, scale ); + + FT_Int do_snapping; + FT_Pos fit_len; + PSH_AlignmentRec align; + + + /* ignore stem alignments when requested through the hint flags */ + if ( ( dimension == 0 && !glyph->do_horz_hints ) || + ( dimension == 1 && !glyph->do_vert_hints ) ) + { + hint->cur_pos = pos; + hint->cur_len = len; + + psh3_hint_set_fitted( hint ); + return; + } + + /* perform stem snapping when requested */ + do_snapping = ( dimension == 0 && glyph->do_horz_snapping ) || + ( dimension == 1 && glyph->do_vert_snapping ); + + hint->cur_len = fit_len = len; + + /* check blue zones for horizontal stems */ + align.align = PSH_BLUE_ALIGN_NONE; + align.align_bot = align.align_top = 0; + + if ( dimension == 1 ) + psh_blues_snap_stem( &globals->blues, + hint->org_pos + hint->org_len, + hint->org_pos, + &align ); + + switch ( align.align ) + { + case PSH_BLUE_ALIGN_TOP: + /* the top of the stem is aligned against a blue zone */ + hint->cur_pos = align.align_top - fit_len; + break; + + case PSH_BLUE_ALIGN_BOT: + /* the bottom of the stem is aligned against a blue zone */ + hint->cur_pos = align.align_bot; + break; + + case PSH_BLUE_ALIGN_TOP | PSH_BLUE_ALIGN_BOT: + /* both edges of the stem are aligned against blue zones */ + hint->cur_pos = align.align_bot; + hint->cur_len = align.align_top - align.align_bot; + break; + + default: + { + PSH3_Hint parent = hint->parent; + + + if ( parent ) + { + FT_Pos par_org_center, par_cur_center; + FT_Pos cur_org_center, cur_delta; + + + /* ensure that parent is already fitted */ + if ( !psh3_hint_is_fitted( parent ) ) + psh3_hint_align( parent, globals, dimension, glyph ); + + par_org_center = parent->org_pos + ( parent->org_len >> 1 ); + par_cur_center = parent->cur_pos + ( parent->cur_len >> 1 ); + cur_org_center = hint->org_pos + ( hint->org_len >> 1 ); + + cur_delta = FT_MulFix( cur_org_center - par_org_center, scale ); + pos = par_cur_center + cur_delta - ( len >> 1 ); + } + + hint->cur_pos = pos; + hint->cur_len = fit_len; + + if ( len <= 64 ) + { + /* the stem is less than one pixel, we will center it */ + /* around the nearest pixel center */ + /* */ + pos = ( pos + ( (len >> 1) & -64 ) ); + len = 64; + } + else + { + len = psh3_dimension_quantize_len( dim, len, 0 ); + } + + /* now that we have a good hinted stem width, try to position */ + /* the stem along a pixel grid integer coordinate */ + hint->cur_pos = pos + psh3_hint_snap_stem_side_delta( pos, len ); + hint->cur_len = len; + } + } + + if ( do_snapping ) + { + pos = hint->cur_pos; + len = hint->cur_len; + + if ( len < 64 ) + len = 64; + else + len = ( len + 32 ) & -64; + + switch ( align.align ) + { + case PSH_BLUE_ALIGN_TOP: + hint->cur_pos = align.align_top - len; + hint->cur_len = len; + break; + + case PSH_BLUE_ALIGN_BOT: + hint->cur_len = len; + break; + + case PSH_BLUE_ALIGN_BOT | PSH_BLUE_ALIGN_TOP: + /* don't touch */ + break; + + + default: + hint->cur_len = len; + if ( len & 64 ) + pos = ( ( pos + ( len >> 1 ) ) & -64 ) + 32; + else + pos = ( pos + ( len >> 1 ) + 32 ) & -64; + + hint->cur_pos = pos - ( len >> 1 ); + hint->cur_len = len; + } + } + + psh3_hint_set_fitted( hint ); + +#ifdef DEBUG_HINTER + if ( ps3_debug_hint_func ) + ps3_debug_hint_func( hint, dimension ); +#endif + } + } + + + static void + psh3_hint_table_align_hints( PSH3_Hint_Table table, + PSH_Globals globals, + FT_Int dimension, + PSH3_Glyph glyph ) + { + PSH3_Hint hint; + FT_UInt count; + +#ifdef DEBUG_HINTER + + PSH_Dimension dim = &globals->dimension[dimension]; + FT_Fixed scale = dim->scale_mult; + FT_Fixed delta = dim->scale_delta; + + + if ( ps_debug_no_vert_hints && dimension == 0 ) + { + ps3_simple_scale( table, scale, delta, dimension ); + return; + } + + if ( ps_debug_no_horz_hints && dimension == 1 ) + { + ps3_simple_scale( table, scale, delta, dimension ); + return; + } + +#endif /* DEBUG_HINTER*/ + + hint = table->hints; + count = table->max_hints; + + for ( ; count > 0; count--, hint++ ) + psh3_hint_align( hint, globals, dimension, glyph ); + } + + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** POINTS INTERPOLATION ROUTINES *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + +#define PSH3_ZONE_MIN -3200000L +#define PSH3_ZONE_MAX +3200000L + +#define xxDEBUG_ZONES + + +#ifdef DEBUG_ZONES + +#include <stdio.h> + + static void + psh3_print_zone( PSH3_Zone zone ) + { + printf( "zone [scale,delta,min,max] = [%.3f,%.3f,%d,%d]\n", + zone->scale / 65536.0, + zone->delta / 64.0, + zone->min, + zone->max ); + } + +#else + +#define psh3_print_zone( x ) do { } while ( 0 ) + +#endif /* DEBUG_ZONES */ + + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** HINTER GLYPH MANAGEMENT *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + +#ifdef COMPUTE_INFLEXS + + /* compute all inflex points in a given glyph */ + static void + psh3_glyph_compute_inflections( PSH3_Glyph glyph ) + { + FT_UInt n; + + + for ( n = 0; n < glyph->num_contours; n++ ) + { + PSH3_Point first, start, end, before, after; + FT_Angle angle_in, angle_seg, angle_out; + FT_Angle diff_in, diff_out; + FT_Int finished = 0; + + + /* we need at least 4 points to create an inflection point */ + if ( glyph->contours[n].count < 4 ) + continue; + + /* compute first segment in contour */ + first = glyph->contours[n].start; + + start = end = first; + do + { + end = end->next; + if ( end == first ) + goto Skip; + + } while ( PSH3_POINT_EQUAL_ORG( end, first ) ); + + angle_seg = PSH3_POINT_ANGLE( start, end ); + + /* extend the segment start whenever possible */ + before = start; + do + { + do + { + start = before; + before = before->prev; + if ( before == first ) + goto Skip; + + } while ( PSH3_POINT_EQUAL_ORG( before, start ) ); + + angle_in = PSH3_POINT_ANGLE( before, start ); + + } while ( angle_in == angle_seg ); + + first = start; + diff_in = FT_Angle_Diff( angle_in, angle_seg ); + + /* now, process all segments in the contour */ + do + { + /* first, extend current segment's end whenever possible */ + after = end; + do + { + do + { + end = after; + after = after->next; + if ( after == first ) + finished = 1; + + } while ( PSH3_POINT_EQUAL_ORG( end, after ) ); + + angle_out = PSH3_POINT_ANGLE( end, after ); + + } while ( angle_out == angle_seg ); + + diff_out = FT_Angle_Diff( angle_seg, angle_out ); + + if ( ( diff_in ^ diff_out ) < 0 ) + { + /* diff_in and diff_out have different signs, we have */ + /* inflection points here... */ + + do + { + psh3_point_set_inflex( start ); + start = start->next; + } + while ( start != end ); + + psh3_point_set_inflex( start ); + } + + start = end; + end = after; + angle_seg = angle_out; + diff_in = diff_out; + + } while ( !finished ); + + Skip: + ; + } + } + +#endif /* COMPUTE_INFLEXS */ + + + static void + psh3_glyph_done( PSH3_Glyph glyph ) + { + FT_Memory memory = glyph->memory; + + + psh3_hint_table_done( &glyph->hint_tables[1], memory ); + psh3_hint_table_done( &glyph->hint_tables[0], memory ); + + FT_FREE( glyph->points ); + FT_FREE( glyph->contours ); + + glyph->num_points = 0; + glyph->num_contours = 0; + + glyph->memory = 0; + } + + + static int + psh3_compute_dir( FT_Pos dx, + FT_Pos dy ) + { + FT_Pos ax, ay; + int result = PSH3_DIR_NONE; + + + ax = ( dx >= 0 ) ? dx : -dx; + ay = ( dy >= 0 ) ? dy : -dy; + + if ( ay * 12 < ax ) + { + /* |dy| <<< |dx| means a near-horizontal segment */ + result = ( dx >= 0 ) ? PSH3_DIR_RIGHT : PSH3_DIR_LEFT; + } + else if ( ax * 12 < ay ) + { + /* |dx| <<< |dy| means a near-vertical segment */ + result = ( dy >= 0 ) ? PSH3_DIR_UP : PSH3_DIR_DOWN; + } + + return result; + } + + + /* load outline point coordinates into hinter glyph */ + static void + psh3_glyph_load_points( PSH3_Glyph glyph, + FT_Int dimension ) + { + FT_Vector* vec = glyph->outline->points; + PSH3_Point point = glyph->points; + FT_UInt count = glyph->num_points; + + + for ( ; count > 0; count--, point++, vec++ ) + { + point->flags2 = 0; + point->hint = NULL; + if ( dimension == 0 ) + { + point->org_u = vec->x; + point->org_v = vec->y; + } + else + { + point->org_u = vec->y; + point->org_v = vec->x; + } + +#ifdef DEBUG_HINTER + point->org_x = vec->x; + point->org_y = vec->y; +#endif + + } + } + + + /* save hinted point coordinates back to outline */ + static void + psh3_glyph_save_points( PSH3_Glyph glyph, + FT_Int dimension ) + { + FT_UInt n; + PSH3_Point point = glyph->points; + FT_Vector* vec = glyph->outline->points; + char* tags = glyph->outline->tags; + + + for ( n = 0; n < glyph->num_points; n++ ) + { + if ( dimension == 0 ) + vec[n].x = point->cur_u; + else + vec[n].y = point->cur_u; + + if ( psh3_point_is_strong( point ) ) + tags[n] |= (char)( ( dimension == 0 ) ? 32 : 64 ); + +#ifdef DEBUG_HINTER + + if ( dimension == 0 ) + { + point->cur_x = point->cur_u; + point->flags_x = point->flags2 | point->flags; + } + else + { + point->cur_y = point->cur_u; + point->flags_y = point->flags2 | point->flags; + } + +#endif + + point++; + } + } + + + static FT_Error + psh3_glyph_init( PSH3_Glyph glyph, + FT_Outline* outline, + PS_Hints ps_hints, + PSH_Globals globals ) + { + FT_Error error; + FT_Memory memory; + + + /* clear all fields */ + FT_MEM_ZERO( glyph, sizeof ( *glyph ) ); + + memory = globals->memory; + + /* allocate and setup points + contours arrays */ + if ( FT_NEW_ARRAY( glyph->points, outline->n_points ) || + FT_NEW_ARRAY( glyph->contours, outline->n_contours ) ) + goto Exit; + + glyph->num_points = outline->n_points; + glyph->num_contours = outline->n_contours; + + { + FT_UInt first = 0, next, n; + PSH3_Point points = glyph->points; + PSH3_Contour contour = glyph->contours; + + + for ( n = 0; n < glyph->num_contours; n++ ) + { + FT_Int count; + PSH3_Point point; + + + next = outline->contours[n] + 1; + count = next - first; + + contour->start = points + first; + contour->count = (FT_UInt)count; + + if ( count > 0 ) + { + point = points + first; + + point->prev = points + next - 1; + point->contour = contour; + + for ( ; count > 1; count-- ) + { + point[0].next = point + 1; + point[1].prev = point; + point++; + point->contour = contour; + } + point->next = points + first; + } + + contour++; + first = next; + } + } + + { + PSH3_Point points = glyph->points; + PSH3_Point point = points; + FT_Vector* vec = outline->points; + FT_UInt n; + + + for ( n = 0; n < glyph->num_points; n++, point++ ) + { + FT_Int n_prev = point->prev - points; + FT_Int n_next = point->next - points; + FT_Pos dxi, dyi, dxo, dyo; + + + if ( !( outline->tags[n] & FT_CURVE_TAG_ON ) ) + point->flags = PSH3_POINT_OFF; + + dxi = vec[n].x - vec[n_prev].x; + dyi = vec[n].y - vec[n_prev].y; + + point->dir_in = (FT_Char)psh3_compute_dir( dxi, dyi ); + + dxo = vec[n_next].x - vec[n].x; + dyo = vec[n_next].y - vec[n].y; + + point->dir_out = (FT_Char)psh3_compute_dir( dxo, dyo ); + + /* detect smooth points */ + if ( point->flags & PSH3_POINT_OFF ) + point->flags |= PSH3_POINT_SMOOTH; + else if ( point->dir_in != PSH3_DIR_NONE || + point->dir_out != PSH3_DIR_NONE ) + { + if ( point->dir_in == point->dir_out ) + point->flags |= PSH3_POINT_SMOOTH; + } + else + { + FT_Angle angle_in, angle_out, diff; + + + angle_in = FT_Atan2( dxi, dyi ); + angle_out = FT_Atan2( dxo, dyo ); + + diff = angle_in - angle_out; + if ( diff < 0 ) + diff = -diff; + + if ( diff > FT_ANGLE_PI ) + diff = FT_ANGLE_2PI - diff; + + if ( diff < FT_ANGLE_PI / 16 ) + point->flags |= PSH3_POINT_SMOOTH; + } + } + } + + glyph->memory = memory; + glyph->outline = outline; + glyph->globals = globals; + +#ifdef COMPUTE_INFLEXS + psh3_glyph_load_points( glyph, 0 ); + psh3_glyph_compute_inflections( glyph ); +#endif /* COMPUTE_INFLEXS */ + + /* now deal with hints tables */ + error = psh3_hint_table_init( &glyph->hint_tables [0], + &ps_hints->dimension[0].hints, + &ps_hints->dimension[0].masks, + &ps_hints->dimension[0].counters, + memory ); + if ( error ) + goto Exit; + + error = psh3_hint_table_init( &glyph->hint_tables [1], + &ps_hints->dimension[1].hints, + &ps_hints->dimension[1].masks, + &ps_hints->dimension[1].counters, + memory ); + if ( error ) + goto Exit; + + Exit: + return error; + } + + + /* compute all extrema in a glyph for a given dimension */ + static void + psh3_glyph_compute_extrema( PSH3_Glyph glyph ) + { + FT_UInt n; + + + /* first of all, compute all local extrema */ + for ( n = 0; n < glyph->num_contours; n++ ) + { + PSH3_Point first = glyph->contours[n].start; + PSH3_Point point, before, after; + + + point = first; + before = point; + after = point; + + do + { + before = before->prev; + if ( before == first ) + goto Skip; + + } while ( before->org_u == point->org_u ); + + first = point = before->next; + + for (;;) + { + after = point; + do + { + after = after->next; + if ( after == first ) + goto Next; + + } while ( after->org_u == point->org_u ); + + if ( before->org_u < point->org_u ) + { + if ( after->org_u < point->org_u ) + { + /* local maximum */ + goto Extremum; + } + } + else /* before->org_u > point->org_u */ + { + if ( after->org_u > point->org_u ) + { + /* local minimum */ + Extremum: + do + { + psh3_point_set_extremum( point ); + point = point->next; + + } while ( point != after ); + } + } + + before = after->prev; + point = after; + + } /* for */ + + Next: + ; + } + + /* for each extrema, determine its direction along the */ + /* orthogonal axis */ + for ( n = 0; n < glyph->num_points; n++ ) + { + PSH3_Point point, before, after; + + + point = &glyph->points[n]; + before = point; + after = point; + + if ( psh3_point_is_extremum( point ) ) + { + do + { + before = before->prev; + if ( before == point ) + goto Skip; + + } while ( before->org_v == point->org_v ); + + do + { + after = after->next; + if ( after == point ) + goto Skip; + + } while ( after->org_v == point->org_v ); + } + + if ( before->org_v < point->org_v && + after->org_v > point->org_v ) + { + psh3_point_set_positive( point ); + } + else if ( before->org_v > point->org_v && + after->org_v < point->org_v ) + { + psh3_point_set_negative( point ); + } + + Skip: + ; + } + } + + +#define PSH3_STRONG_THRESHOLD 30 + + + /* major_dir is the direction for points on the bottom/left of the stem; */ + /* Points on the top/right of the stem will have a direction of */ + /* -major_dir. */ + + static void + psh3_hint_table_find_strong_point( PSH3_Hint_Table table, + PSH3_Point point, + FT_Int major_dir ) + { + PSH3_Hint* sort = table->sort; + FT_UInt num_hints = table->num_hints; + FT_Int point_dir = 0; + + + if ( PSH3_DIR_COMPARE( point->dir_in, major_dir ) ) + point_dir = point->dir_in; + + else if ( PSH3_DIR_COMPARE( point->dir_out, major_dir ) ) + point_dir = point->dir_out; + + if ( point_dir ) + { + FT_UInt flag; + + + for ( ; num_hints > 0; num_hints--, sort++ ) + { + PSH3_Hint hint = sort[0]; + FT_Pos d; + + + if ( point_dir == major_dir ) + { + flag = PSH3_POINT_EDGE_MIN; + d = point->org_u - hint->org_pos; + + if ( ABS( d ) < PSH3_STRONG_THRESHOLD ) + { + Is_Strong: + psh3_point_set_strong( point ); + point->flags2 |= flag; + point->hint = hint; + break; + } + } + else if ( point_dir == -major_dir ) + { + flag = PSH3_POINT_EDGE_MAX; + d = point->org_u - hint->org_pos - hint->org_len; + + if ( ABS( d ) < PSH3_STRONG_THRESHOLD ) + goto Is_Strong; + } + } + } + +#if 1 + else if ( psh3_point_is_extremum( point ) ) + { + /* treat extrema as special cases for stem edge alignment */ + FT_UInt min_flag, max_flag; + + + if ( major_dir == PSH3_DIR_HORIZONTAL ) + { + min_flag = PSH3_POINT_POSITIVE; + max_flag = PSH3_POINT_NEGATIVE; + } + else + { + min_flag = PSH3_POINT_NEGATIVE; + max_flag = PSH3_POINT_POSITIVE; + } + + for ( ; num_hints > 0; num_hints--, sort++ ) + { + PSH3_Hint hint = sort[0]; + FT_Pos d, flag; + + + if ( point->flags2 & min_flag ) + { + flag = PSH3_POINT_EDGE_MIN; + d = point->org_u - hint->org_pos; + + if ( ABS( d ) < PSH3_STRONG_THRESHOLD ) + { + Is_Strong2: + point->flags2 |= flag; + point->hint = hint; + psh3_point_set_strong( point ); + break; + } + } + else if ( point->flags2 & max_flag ) + { + flag = PSH3_POINT_EDGE_MAX; + d = point->org_u - hint->org_pos - hint->org_len; + + if ( ABS( d ) < PSH3_STRONG_THRESHOLD ) + goto Is_Strong2; + } + + if ( point->org_u >= hint->org_pos && + point->org_u <= hint->org_pos + hint->org_len ) + { + point->hint = hint; + } + } + } + +#endif /* 1 */ + } + + + /* find strong points in a glyph */ + static void + psh3_glyph_find_strong_points( PSH3_Glyph glyph, + FT_Int dimension ) + { + /* a point is strong if it is located on a stem */ + /* edge and has an "in" or "out" tangent to the hint's direction */ + { + PSH3_Hint_Table table = &glyph->hint_tables[dimension]; + PS_Mask mask = table->hint_masks->masks; + FT_UInt num_masks = table->hint_masks->num_masks; + FT_UInt first = 0; + FT_Int major_dir = dimension == 0 ? PSH3_DIR_VERTICAL + : PSH3_DIR_HORIZONTAL; + + + /* process secondary hints to "selected" points */ + if ( num_masks > 1 && glyph->num_points > 0 ) + { + first = mask->end_point; + mask++; + for ( ; num_masks > 1; num_masks--, mask++ ) + { + FT_UInt next; + FT_Int count; + + + next = mask->end_point; + count = next - first; + if ( count > 0 ) + { + PSH3_Point point = glyph->points + first; + + + psh3_hint_table_activate_mask( table, mask ); + + for ( ; count > 0; count--, point++ ) + psh3_hint_table_find_strong_point( table, point, major_dir ); + } + first = next; + } + } + + /* process primary hints for all points */ + if ( num_masks == 1 ) + { + FT_UInt count = glyph->num_points; + PSH3_Point point = glyph->points; + + + psh3_hint_table_activate_mask( table, table->hint_masks->masks ); + for ( ; count > 0; count--, point++ ) + { + if ( !psh3_point_is_strong( point ) ) + psh3_hint_table_find_strong_point( table, point, major_dir ); + } + } + + /* now, certain points may have been attached to hint and */ + /* not marked as strong; update their flags then */ + { + FT_UInt count = glyph->num_points; + PSH3_Point point = glyph->points; + + + for ( ; count > 0; count--, point++ ) + if ( point->hint && !psh3_point_is_strong( point ) ) + psh3_point_set_strong( point ); + } + } + } + + + /* interpolate strong points with the help of hinted coordinates */ + static void + psh3_glyph_interpolate_strong_points( PSH3_Glyph glyph, + FT_Int dimension ) + { + PSH_Dimension dim = &glyph->globals->dimension[dimension]; + FT_Fixed scale = dim->scale_mult; + + + { + FT_UInt count = glyph->num_points; + PSH3_Point point = glyph->points; + + + for ( ; count > 0; count--, point++ ) + { + PSH3_Hint hint = point->hint; + + + if ( hint ) + { + FT_Pos delta; + + + if ( psh3_point_is_edge_min( point ) ) + { + point->cur_u = hint->cur_pos; + } + else if ( psh3_point_is_edge_max( point ) ) + { + point->cur_u = hint->cur_pos + hint->cur_len; + } + else + { + delta = point->org_u - hint->org_pos; + + if ( delta <= 0 ) + point->cur_u = hint->cur_pos + FT_MulFix( delta, scale ); + + else if ( delta >= hint->org_len ) + point->cur_u = hint->cur_pos + hint->cur_len + + FT_MulFix( delta - hint->org_len, scale ); + + else if ( hint->org_len > 0 ) + point->cur_u = hint->cur_pos + + FT_MulDiv( delta, hint->cur_len, + hint->org_len ); + else + point->cur_u = hint->cur_pos; + } + psh3_point_set_fitted( point ); + } + } + } + } + + + static void + psh3_glyph_interpolate_normal_points( PSH3_Glyph glyph, + FT_Int dimension ) + { + +#if 1 + + PSH_Dimension dim = &glyph->globals->dimension[dimension]; + FT_Fixed scale = dim->scale_mult; + + + /* first technique: a point is strong if it is a local extrema */ + { + FT_UInt count = glyph->num_points; + PSH3_Point point = glyph->points; + + + for ( ; count > 0; count--, point++ ) + { + if ( psh3_point_is_strong( point ) ) + continue; + + /* sometimes, some local extremas are smooth points */ + if ( psh3_point_is_smooth( point ) ) + { + if ( point->dir_in == PSH3_DIR_NONE || + point->dir_in != point->dir_out ) + continue; + + if ( !psh3_point_is_extremum( point ) && + !psh3_point_is_inflex( point ) ) + continue; + + point->flags &= ~PSH3_POINT_SMOOTH; + } + + /* find best enclosing point coordinates */ + { + PSH3_Point before = 0; + PSH3_Point after = 0; + + FT_Pos diff_before = -32000; + FT_Pos diff_after = 32000; + FT_Pos u = point->org_u; + + FT_Int count2 = glyph->num_points; + PSH3_Point cur = glyph->points; + + + for ( ; count2 > 0; count2--, cur++ ) + { + if ( psh3_point_is_strong( cur ) ) + { + FT_Pos diff = cur->org_u - u;; + + + if ( diff <= 0 ) + { + if ( diff > diff_before ) + { + diff_before = diff; + before = cur; + } + } + else if ( diff >= 0 ) + { + if ( diff < diff_after ) + { + diff_after = diff; + after = cur; + } + } + } + } + + if ( !before ) + { + if ( !after ) + continue; + + /* we are before the first strong point coordinate; */ + /* simply translate the point */ + point->cur_u = after->cur_u + + FT_MulFix( point->org_u - after->org_u, scale ); + } + else if ( !after ) + { + /* we are after the last strong point coordinate; */ + /* simply translate the point */ + point->cur_u = before->cur_u + + FT_MulFix( point->org_u - before->org_u, scale ); + } + else + { + if ( diff_before == 0 ) + point->cur_u = before->cur_u; + + else if ( diff_after == 0 ) + point->cur_u = after->cur_u; + + else + point->cur_u = before->cur_u + + FT_MulDiv( u - before->org_u, + after->cur_u - before->cur_u, + after->org_u - before->org_u ); + } + + psh3_point_set_fitted( point ); + } + } + } + +#endif /* 1 */ + + } + + + /* interpolate other points */ + static void + psh3_glyph_interpolate_other_points( PSH3_Glyph glyph, + FT_Int dimension ) + { + PSH_Dimension dim = &glyph->globals->dimension[dimension]; + FT_Fixed scale = dim->scale_mult; + FT_Fixed delta = dim->scale_delta; + PSH3_Contour contour = glyph->contours; + FT_UInt num_contours = glyph->num_contours; + + + for ( ; num_contours > 0; num_contours--, contour++ ) + { + PSH3_Point start = contour->start; + PSH3_Point first, next, point; + FT_UInt fit_count; + + + /* count the number of strong points in this contour */ + next = start + contour->count; + fit_count = 0; + first = 0; + + for ( point = start; point < next; point++ ) + if ( psh3_point_is_fitted( point ) ) + { + if ( !first ) + first = point; + + fit_count++; + } + + /* if there are less than 2 fitted points in the contour, we */ + /* simply scale and eventually translate the contour points */ + if ( fit_count < 2 ) + { + if ( fit_count == 1 ) + delta = first->cur_u - FT_MulFix( first->org_u, scale ); + + for ( point = start; point < next; point++ ) + if ( point != first ) + point->cur_u = FT_MulFix( point->org_u, scale ) + delta; + + goto Next_Contour; + } + + /* there are more than 2 strong points in this contour; we */ + /* need to interpolate weak points between them */ + start = first; + do + { + point = first; + + /* skip consecutive fitted points */ + for (;;) + { + next = first->next; + if ( next == start ) + goto Next_Contour; + + if ( !psh3_point_is_fitted( next ) ) + break; + + first = next; + } + + /* find next fitted point after unfitted one */ + for (;;) + { + next = next->next; + if ( psh3_point_is_fitted( next ) ) + break; + } + + /* now interpolate between them */ + { + FT_Pos org_a, org_ab, cur_a, cur_ab; + FT_Pos org_c, org_ac, cur_c; + FT_Fixed scale_ab; + + + if ( first->org_u <= next->org_u ) + { + org_a = first->org_u; + cur_a = first->cur_u; + org_ab = next->org_u - org_a; + cur_ab = next->cur_u - cur_a; + } + else + { + org_a = next->org_u; + cur_a = next->cur_u; + org_ab = first->org_u - org_a; + cur_ab = first->cur_u - cur_a; + } + + scale_ab = 0x10000L; + if ( org_ab > 0 ) + scale_ab = FT_DivFix( cur_ab, org_ab ); + + point = first->next; + do + { + org_c = point->org_u; + org_ac = org_c - org_a; + + if ( org_ac <= 0 ) + { + /* on the left of the interpolation zone */ + cur_c = cur_a + FT_MulFix( org_ac, scale ); + } + else if ( org_ac >= org_ab ) + { + /* on the right on the interpolation zone */ + cur_c = cur_a + cur_ab + FT_MulFix( org_ac - org_ab, scale ); + } + else + { + /* within the interpolation zone */ + cur_c = cur_a + FT_MulFix( org_ac, scale_ab ); + } + + point->cur_u = cur_c; + + point = point->next; + + } while ( point != next ); + } + + /* keep going until all points in the contours have been processed */ + first = next; + + } while ( first != start ); + + Next_Contour: + ; + } + } + + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** HIGH-LEVEL INTERFACE *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + + FT_Error + ps3_hints_apply( PS_Hints ps_hints, + FT_Outline* outline, + PSH_Globals globals, + FT_Render_Mode hint_mode ) + { + PSH3_GlyphRec glyphrec; + PSH3_Glyph glyph = &glyphrec; + FT_Error error; +#ifdef DEBUG_HINTER + FT_Memory memory; +#endif + FT_Int dimension; + + +#ifdef DEBUG_HINTER + + memory = globals->memory; + + if ( ps3_debug_glyph ) + { + psh3_glyph_done( ps3_debug_glyph ); + FT_FREE( ps3_debug_glyph ); + } + + if ( FT_NEW( glyph ) ) + return error; + + ps3_debug_glyph = glyph; + +#endif /* DEBUG_HINTER */ + + error = psh3_glyph_init( glyph, outline, ps_hints, globals ); + if ( error ) + goto Exit; + + glyph->do_horz_hints = 1; + glyph->do_vert_hints = 1; + + glyph->do_horz_snapping = FT_BOOL( hint_mode == FT_RENDER_MODE_MONO || + hint_mode == FT_RENDER_MODE_LCD ); + + glyph->do_vert_snapping = FT_BOOL( hint_mode == FT_RENDER_MODE_MONO || + hint_mode == FT_RENDER_MODE_LCD_V ); + + for ( dimension = 0; dimension < 2; dimension++ ) + { + /* load outline coordinates into glyph */ + psh3_glyph_load_points( glyph, dimension ); + + /* compute local extrema */ + psh3_glyph_compute_extrema( glyph ); + + /* compute aligned stem/hints positions */ + psh3_hint_table_align_hints( &glyph->hint_tables[dimension], + glyph->globals, + dimension, + glyph ); + + /* find strong points, align them, then interpolate others */ + psh3_glyph_find_strong_points( glyph, dimension ); + psh3_glyph_interpolate_strong_points( glyph, dimension ); + psh3_glyph_interpolate_normal_points( glyph, dimension ); + psh3_glyph_interpolate_other_points( glyph, dimension ); + + /* save hinted coordinates back to outline */ + psh3_glyph_save_points( glyph, dimension ); + } + + Exit: + +#ifndef DEBUG_HINTER + psh3_glyph_done( glyph ); +#endif + + return error; + } + + +/* END */ |