ref: 79c64a79a248c31733d4ec0ff9fe1a1e57a58f51
dir: /libfreetype/pshalgo1.c/
/***************************************************************************/ /* */ /* pshalgo1.c */ /* */ /* PostScript hinting algorithm 1 (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 "pshalgo1.h" #undef FT_COMPONENT #define FT_COMPONENT trace_pshalgo1 #ifdef DEBUG_HINTER PSH1_Hint_Table ps1_debug_hint_table = 0; PSH1_HintFunc ps1_debug_hint_func = 0; #endif /************************************************************************/ /************************************************************************/ /***** *****/ /***** BASIC HINTS RECORDINGS *****/ /***** *****/ /************************************************************************/ /************************************************************************/ /* return true iff two stem hints overlap */ static FT_Int psh1_hint_overlap( PSH1_Hint hint1, PSH1_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 psh1_hint_table_done( PSH1_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 psh1_hint_table_deactivate( PSH1_Hint_Table table ) { FT_UInt count = table->max_hints; PSH1_Hint hint = table->hints; for ( ; count > 0; count--, hint++ ) { psh1_hint_deactivate( hint ); hint->order = -1; } } /* internal function used to record a new hint */ static void psh1_hint_table_record( PSH1_Hint_Table table, FT_UInt idx ) { PSH1_Hint hint = table->hints + idx; if ( idx >= table->max_hints ) { FT_ERROR(( "%s.activate: invalid hint index %d\n", idx )); return; } /* ignore active hints */ if ( psh1_hint_is_active( hint ) ) return; psh1_hint_activate( hint ); /* now scan the current active hint set in order to determine */ /* if we are overlapping with another segment */ { PSH1_Hint* sorted = table->sort_global; FT_UInt count = table->num_hints; PSH1_Hint hint2; hint->parent = 0; for ( ; count > 0; count--, sorted++ ) { hint2 = sorted[0]; if ( psh1_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(( "%s.activate: too many sorted hints! BUG!\n", "ps.fitter" )); } static void psh1_hint_table_record_mask( PSH1_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; if ( limit != table->max_hints ) FT_ERROR(( "%s.activate_mask: invalid bit count (%d instead of %d)\n", "ps.fitter", hint_mask->num_bits, table->max_hints )); for ( idx = 0; idx < limit; idx++ ) { if ( mask == 0 ) { val = *cursor++; mask = 0x80; } if ( val & mask ) psh1_hint_table_record( table, idx ); mask >>= 1; } } /* create hints table */ static FT_Error psh1_hint_table_init( PSH1_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 */ { PSH1_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++ ) psh1_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(( "%s.init: missing/incorrect hint masks!\n" )); Count = table->max_hints; for ( Index = 0; Index < Count; Index++ ) psh1_hint_table_record( table, Index ); } Exit: return error; } static void psh1_hint_table_activate_mask( PSH1_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; psh1_hint_table_deactivate( table ); for ( idx = 0; idx < limit; idx++ ) { if ( mask == 0 ) { val = *cursor++; mask = 0x80; } if ( val & mask ) { PSH1_Hint hint = &table->hints[idx]; if ( !psh1_hint_is_active( hint ) ) { PSH1_Hint* sort = table->sort; FT_UInt count2; PSH1_Hint hint2; for ( count2 = count; count2 > 0; count2--, sort++ ) { hint2 = sort[0]; if ( psh1_hint_overlap( hint, hint2 ) ) { FT_ERROR(( "%s.activate_mask: found overlapping hints\n", "psf.hint" )); break; } } if ( count2 == 0 ) { psh1_hint_activate( hint ); if ( count < table->max_hints ) table->sort[count++] = hint; else FT_ERROR(( "%s.activate_mask: too many active hints\n", "psf.hint" )); } } } 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; PSH1_Hint hint1, hint2; PSH1_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 *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ #ifdef DEBUG_HINTER void ps_simple_scale( PSH1_Hint_Table table, FT_Fixed scale, FT_Fixed delta, FT_Int vertical ) { PSH1_Hint hint; FT_UInt count; for ( count = 0; count < table->num_hints; count++ ) { hint = table->sort[count]; if ( psh1_hint_is_active( hint ) ) { hint->cur_pos = FT_MulFix( hint->org_pos, scale ) + delta; hint->cur_len = FT_MulFix( hint->org_len, scale ); if ( ps1_debug_hint_func ) ps1_debug_hint_func( hint, vertical ); } } } #endif FT_LOCAL_DEF( FT_Error ) psh1_hint_table_optimize( PSH1_Hint_Table table, PSH_Globals globals, FT_Outline* outline, FT_Int vertical ) { PSH_Dimension dim = &globals->dimension[vertical]; FT_Fixed scale = dim->scale_mult; FT_Fixed delta = dim->scale_delta; FT_UNUSED( outline ); #ifdef DEBUG_HINTER if ( ps_debug_no_vert_hints && vertical ) { ps_simple_scale( table, scale, delta, vertical ); return 0; } if ( ps_debug_no_horz_hints && !vertical ) { ps_simple_scale( table, scale, delta, vertical ); return 0; } #endif /* XXXX: for now, we only scale the hints to test all other aspects */ /* of the PostScript hinter */ { PSH1_Hint hint; FT_UInt count; for ( count = 0; count < table->num_hints; count++ ) { hint = table->sort[count]; if ( psh1_hint_is_active( hint ) ) { #if 1 FT_Pos pos = FT_MulFix( hint->org_pos, scale ) + delta; FT_Pos len = FT_MulFix( hint->org_len, scale ); FT_Pos fit_center; FT_Pos fit_len; PSH_AlignmentRec align; /* compute fitted width/height */ fit_len = psh_dimension_snap_width( dim, hint->org_len ); if ( fit_len < 64 ) fit_len = 64; else fit_len = ( fit_len + 32 ) & -64; hint->cur_len = fit_len; /* check blue zones for horizontal stems */ align.align = PSH_BLUE_ALIGN_NONE; align.align_bot = align.align_top = 0; if ( !vertical ) { 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: /* normal processing */ if ( ( fit_len / 64 ) & 1 ) { /* odd number of pixels */ fit_center = ( ( pos + ( len >> 1 ) ) & -64 ) + 32; } else { /* even number of pixels */ fit_center = ( pos + ( len >> 1 ) + 32 ) & -64; } hint->cur_pos = fit_center - ( fit_len >> 1 ); } # else hint->cur_pos = ( FT_MulFix( hint->org_pos, scale ) + delta + 32 ) & -64; hint->cur_len = FT_MulFix( hint->org_len, scale ); # endif #ifdef DEBUG_HINTER if ( ps1_debug_hint_func ) ps1_debug_hint_func( hint, vertical ); #endif } } } return 0; } /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** POINTS INTERPOLATION ROUTINES *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ #define PSH1_ZONE_MIN -3200000 #define PSH1_ZONE_MAX +3200000 #define xxDEBUG_ZONES #ifdef DEBUG_ZONES #include <stdio.h> static void psh1_print_zone( PSH1_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 psh1_print_zone( x ) do { } while ( 0 ) #endif /* setup interpolation zones once the hints have been grid-fitted */ /* by the optimizer */ static void psh1_hint_table_setup_zones( PSH1_Hint_Table table, FT_Fixed scale, FT_Fixed delta ) { FT_UInt count; PSH1_Zone zone; PSH1_Hint *sort, hint, hint2; zone = table->zones; /* special case, no hints defined */ if ( table->num_hints == 0 ) { zone->scale = scale; zone->delta = delta; zone->min = PSH1_ZONE_MIN; zone->max = PSH1_ZONE_MAX; table->num_zones = 1; table->zone = zone; return; } /* the first zone is before the first hint */ /* x' = (x-x0)*s + x0' = x*s + ( x0' - x0*s ) */ sort = table->sort; hint = sort[0]; zone->scale = scale; zone->delta = hint->cur_pos - FT_MulFix( hint->org_pos, scale ); zone->min = PSH1_ZONE_MIN; zone->max = hint->org_pos; psh1_print_zone( zone ); zone++; for ( count = table->num_hints; count > 0; count-- ) { FT_Fixed scale2; if ( hint->org_len > 0 ) { /* setup a zone for inner-stem interpolation */ /* (x' - x0') = (x - x0)*(x1'-x0')/(x1-x0) */ /* x' = x*s2 + x0' - x0*s2 */ scale2 = FT_DivFix( hint->cur_len, hint->org_len ); zone->scale = scale2; zone->min = hint->org_pos; zone->max = hint->org_pos + hint->org_len; zone->delta = hint->cur_pos - FT_MulFix( zone->min, scale2 ); psh1_print_zone( zone ); zone++; } if ( count == 1 ) break; sort++; hint2 = sort[0]; /* setup zone for inter-stem interpolation */ /* (x'-x1') = (x-x1)*(x2'-x1')/(x2-x1) */ /* x' = x*s3 + x1' - x1*s3 */ scale2 = FT_DivFix( hint2->cur_pos - (hint->cur_pos + hint->cur_len), hint2->org_pos - (hint->org_pos + hint->org_len) ); zone->scale = scale2; zone->min = hint->org_pos + hint->org_len; zone->max = hint2->org_pos; zone->delta = hint->cur_pos + hint->cur_len - FT_MulFix( zone->min, scale2 ); psh1_print_zone( zone ); zone++; hint = hint2; } /* the last zone */ zone->scale = scale; zone->min = hint->org_pos + hint->org_len; zone->max = PSH1_ZONE_MAX; zone->delta = hint->cur_pos + hint->cur_len - FT_MulFix( zone->min, scale ); psh1_print_zone( zone ); zone++; table->num_zones = zone - table->zones; table->zone = table->zones; } /* tune a single coordinate with the current interpolation zones */ static FT_Pos psh1_hint_table_tune_coord( PSH1_Hint_Table table, FT_Int coord ) { PSH1_Zone zone; zone = table->zone; if ( coord < zone->min ) { do { if ( zone == table->zones ) break; zone--; } while ( coord < zone->min ); table->zone = zone; } else if ( coord > zone->max ) { do { if ( zone == table->zones + table->num_zones - 1 ) break; zone++; } while ( coord > zone->max ); table->zone = zone; } return FT_MulFix( coord, zone->scale ) + zone->delta; } /* tune a given outline with current interpolation zones. */ /* The function only works in a single dimension. */ static void psh1_hint_table_tune_outline( PSH1_Hint_Table table, FT_Outline* outline, PSH_Globals globals, FT_Int vertical ) { FT_UInt count, first, last; PS_Mask_Table hint_masks = table->hint_masks; PS_Mask mask; PSH_Dimension dim = &globals->dimension[vertical]; FT_Fixed scale = dim->scale_mult; FT_Fixed delta = dim->scale_delta; if ( hint_masks && hint_masks->num_masks > 0 ) { first = 0; mask = hint_masks->masks; count = hint_masks->num_masks; for ( ; count > 0; count--, mask++ ) { last = mask->end_point; if ( last > first ) { FT_Vector* vec; FT_Int count2; psh1_hint_table_activate_mask( table, mask ); psh1_hint_table_optimize( table, globals, outline, vertical ); psh1_hint_table_setup_zones( table, scale, delta ); last = mask->end_point; vec = outline->points + first; count2 = last - first; for ( ; count2 > 0; count2--, vec++ ) { FT_Pos x, *px; px = vertical ? &vec->x : &vec->y; x = *px; *px = psh1_hint_table_tune_coord( table, (FT_Int)x ); } } first = last; } } else /* no hints in this glyph, simply scale the outline */ { FT_Vector* vec; vec = outline->points; count = outline->n_points; if ( vertical ) { for ( ; count > 0; count--, vec++ ) vec->x = FT_MulFix( vec->x, scale ) + delta; } else { for ( ; count > 0; count--, vec++ ) vec->y = FT_MulFix( vec->y, scale ) + delta; } } } /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** HIGH-LEVEL INTERFACE *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ FT_Error ps1_hints_apply( PS_Hints ps_hints, FT_Outline* outline, PSH_Globals globals, FT_Render_Mode hint_mode ) { PSH1_Hint_TableRec hints; FT_Error error = 0; FT_Int dimension; FT_UNUSED( hint_mode ); for ( dimension = 1; dimension >= 0; dimension-- ) { PS_Dimension dim = &ps_hints->dimension[dimension]; /* initialize hints table */ FT_MEM_ZERO( &hints, sizeof ( hints ) ); error = psh1_hint_table_init( &hints, &dim->hints, &dim->masks, &dim->counters, ps_hints->memory ); if ( error ) goto Exit; psh1_hint_table_tune_outline( &hints, outline, globals, dimension ); psh1_hint_table_done( &hints, ps_hints->memory ); } Exit: return error; } /* END */