| /**************************************************************************** |
| * |
| * pshalgo.c |
| * |
| * PostScript hinting algorithm (body). |
| * |
| * Copyright (C) 2001-2022 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 <freetype/internal/ftobjs.h> |
| #include <freetype/internal/ftdebug.h> |
| #include <freetype/internal/ftcalc.h> |
| #include "pshalgo.h" |
| |
| #include "pshnterr.h" |
| |
| |
| #undef FT_COMPONENT |
| #define FT_COMPONENT pshalgo |
| |
| |
| #ifdef DEBUG_HINTER |
| PSH_Hint_Table ps_debug_hint_table = NULL; |
| PSH_HintFunc ps_debug_hint_func = NULL; |
| PSH_Glyph ps_debug_glyph = NULL; |
| #endif |
| |
| |
| #define COMPUTE_INFLEXS /* compute inflection points to optimize `S' */ |
| /* and similar glyphs */ |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** BASIC HINTS RECORDINGS *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| /* return true if two stem hints overlap */ |
| static FT_Int |
| psh_hint_overlap( PSH_Hint hint1, |
| PSH_Hint hint2 ) |
| { |
| return ADD_INT( hint1->org_pos, hint1->org_len ) >= hint2->org_pos && |
| ADD_INT( hint2->org_pos, hint2->org_len ) >= hint1->org_pos; |
| } |
| |
| |
| /* destroy hints table */ |
| static void |
| psh_hint_table_done( PSH_Hint_Table table, |
| FT_Memory memory ) |
| { |
| FT_FREE( table->zones ); |
| table->num_zones = 0; |
| table->zone = NULL; |
| |
| FT_FREE( table->sort ); |
| FT_FREE( table->hints ); |
| table->num_hints = 0; |
| table->max_hints = 0; |
| table->sort_global = NULL; |
| } |
| |
| |
| /* deactivate all hints in a table */ |
| static void |
| psh_hint_table_deactivate( PSH_Hint_Table table ) |
| { |
| FT_UInt count = table->max_hints; |
| PSH_Hint hint = table->hints; |
| |
| |
| for ( ; count > 0; count--, hint++ ) |
| { |
| psh_hint_deactivate( hint ); |
| hint->order = -1; |
| } |
| } |
| |
| |
| /* internal function to record a new hint */ |
| static void |
| psh_hint_table_record( PSH_Hint_Table table, |
| FT_UInt idx ) |
| { |
| PSH_Hint hint = table->hints + idx; |
| |
| |
| if ( idx >= table->max_hints ) |
| { |
| FT_TRACE0(( "psh_hint_table_record: invalid hint index %d\n", idx )); |
| return; |
| } |
| |
| /* ignore active hints */ |
| if ( psh_hint_is_active( hint ) ) |
| return; |
| |
| psh_hint_activate( hint ); |
| |
| /* now scan the current active hint set to check */ |
| /* whether `hint' overlaps with another hint */ |
| { |
| PSH_Hint* sorted = table->sort_global; |
| FT_UInt count = table->num_hints; |
| PSH_Hint hint2; |
| |
| |
| hint->parent = NULL; |
| for ( ; count > 0; count--, sorted++ ) |
| { |
| hint2 = sorted[0]; |
| |
| if ( psh_hint_overlap( hint, hint2 ) ) |
| { |
| hint->parent = hint2; |
| break; |
| } |
| } |
| } |
| |
| if ( table->num_hints < table->max_hints ) |
| table->sort_global[table->num_hints++] = hint; |
| else |
| FT_TRACE0(( "psh_hint_table_record: too many sorted hints! BUG!\n" )); |
| } |
| |
| |
| static void |
| psh_hint_table_record_mask( PSH_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 ) |
| psh_hint_table_record( table, idx ); |
| |
| mask >>= 1; |
| } |
| } |
| |
| |
| /* create hints table */ |
| static FT_Error |
| psh_hint_table_init( PSH_Hint_Table table, |
| PS_Hint_Table hints, |
| PS_Mask_Table hint_masks, |
| PS_Mask_Table counter_masks, |
| FT_Memory memory ) |
| { |
| FT_UInt count; |
| FT_Error error; |
| |
| FT_UNUSED( counter_masks ); |
| |
| |
| count = hints->num_hints; |
| |
| /* 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 = FT_OFFSET( table->sort, count ); |
| table->num_hints = 0; |
| table->num_zones = 0; |
| table->zone = NULL; |
| |
| /* initialize the `table->hints' array */ |
| { |
| PSH_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 ) |
| { |
| PS_Mask mask = hint_masks->masks; |
| |
| |
| count = hint_masks->num_masks; |
| table->hint_masks = hint_masks; |
| |
| for ( ; count > 0; count--, mask++ ) |
| psh_hint_table_record_mask( table, mask ); |
| } |
| |
| /* finally, do a linear parse in case some hints were left alone */ |
| if ( table->num_hints != table->max_hints ) |
| { |
| FT_UInt idx; |
| |
| |
| FT_TRACE0(( "psh_hint_table_init: missing/incorrect hint masks\n" )); |
| |
| count = table->max_hints; |
| for ( idx = 0; idx < count; idx++ ) |
| psh_hint_table_record( table, idx ); |
| } |
| |
| Exit: |
| return error; |
| } |
| |
| |
| static void |
| psh_hint_table_activate_mask( PSH_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; |
| |
| psh_hint_table_deactivate( table ); |
| |
| for ( idx = 0; idx < limit; idx++ ) |
| { |
| if ( mask == 0 ) |
| { |
| val = *cursor++; |
| mask = 0x80; |
| } |
| |
| if ( val & mask ) |
| { |
| PSH_Hint hint = &table->hints[idx]; |
| |
| |
| if ( !psh_hint_is_active( hint ) ) |
| { |
| FT_UInt count2; |
| |
| #if 0 |
| PSH_Hint* sort = table->sort; |
| PSH_Hint hint2; |
| |
| |
| for ( count2 = count; count2 > 0; count2--, sort++ ) |
| { |
| hint2 = sort[0]; |
| if ( psh_hint_overlap( hint, hint2 ) ) |
| FT_TRACE0(( "psh_hint_table_activate_mask:" |
| " found overlapping hints\n" )) |
| } |
| #else |
| count2 = 0; |
| #endif |
| |
| if ( count2 == 0 ) |
| { |
| psh_hint_activate( hint ); |
| if ( count < table->max_hints ) |
| table->sort[count++] = hint; |
| else |
| FT_TRACE0(( "psh_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_UInt i1, i2; |
| PSH_Hint hint1, hint2; |
| PSH_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 < count; i1++ ) |
| { |
| hint1 = sort[i1]; |
| /* this loop stops when i2 wraps around after reaching 0 */ |
| for ( i2 = i1 - 1; i2 < i1; i2-- ) |
| { |
| hint2 = sort[i2]; |
| |
| if ( hint2->org_pos < hint1->org_pos ) |
| break; |
| |
| sort[i2 + 1] = hint2; |
| sort[i2] = hint1; |
| } |
| } |
| } |
| } |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** HINTS GRID-FITTING AND OPTIMIZATION *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| #if 1 |
| static FT_Pos |
| psh_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 = FT_PIX_ROUND( len ); |
| } |
| |
| if ( do_snapping ) |
| len = FT_PIX_ROUND( len ); |
| |
| return len; |
| } |
| #endif /* 0 */ |
| |
| |
| #ifdef DEBUG_HINTER |
| |
| static void |
| ps_simple_scale( PSH_Hint_Table table, |
| FT_Fixed scale, |
| FT_Fixed delta, |
| FT_Int dimension ) |
| { |
| FT_UInt count; |
| |
| |
| for ( count = 0; count < table->max_hints; count++ ) |
| { |
| PSH_Hint hint = table->hints + count; |
| |
| |
| hint->cur_pos = FT_MulFix( hint->org_pos, scale ) + delta; |
| hint->cur_len = FT_MulFix( hint->org_len, scale ); |
| |
| if ( ps_debug_hint_func ) |
| ps_debug_hint_func( hint, dimension ); |
| } |
| } |
| |
| #endif /* DEBUG_HINTER */ |
| |
| |
| static FT_Fixed |
| psh_hint_snap_stem_side_delta( FT_Fixed pos, |
| FT_Fixed len ) |
| { |
| FT_Fixed delta1 = FT_PIX_ROUND( pos ) - pos; |
| FT_Fixed delta2 = FT_PIX_ROUND( pos + len ) - pos - len; |
| |
| |
| if ( FT_ABS( delta1 ) <= FT_ABS( delta2 ) ) |
| return delta1; |
| else |
| return delta2; |
| } |
| |
| |
| static void |
| psh_hint_align( PSH_Hint hint, |
| PSH_Globals globals, |
| FT_Int dimension, |
| PSH_Glyph glyph ) |
| { |
| PSH_Dimension dim = &globals->dimension[dimension]; |
| FT_Fixed scale = dim->scale_mult; |
| FT_Fixed delta = dim->scale_delta; |
| |
| |
| if ( !psh_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; |
| |
| psh_hint_set_fitted( hint ); |
| return; |
| } |
| |
| /* perform stem snapping when requested - this is necessary |
| * for monochrome and LCD hinting modes only |
| */ |
| 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, |
| ADD_INT( 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: |
| { |
| PSH_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 ( !psh_hint_is_fitted( parent ) ) |
| psh_hint_align( parent, globals, dimension, glyph ); |
| |
| /* keep original relation between hints, this is, use the */ |
| /* scaled distance between the centers of the hints to */ |
| /* compute the new position */ |
| 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; |
| |
| /* Stem adjustment tries to snap stem widths to standard |
| * ones. This is important to prevent unpleasant rounding |
| * artefacts. |
| */ |
| if ( glyph->do_stem_adjust ) |
| { |
| if ( len <= 64 ) |
| { |
| /* the stem is less than one pixel; we will center it |
| * around the nearest pixel center |
| */ |
| if ( len >= 32 ) |
| { |
| /* This is a special case where we also widen the stem |
| * and align it to the pixel grid. |
| * |
| * stem_center = pos + (len/2) |
| * nearest_pixel_center = FT_ROUND(stem_center-32)+32 |
| * new_pos = nearest_pixel_center-32 |
| * = FT_ROUND(stem_center-32) |
| * = FT_FLOOR(stem_center-32+32) |
| * = FT_FLOOR(stem_center) |
| * new_len = 64 |
| */ |
| pos = FT_PIX_FLOOR( pos + ( len >> 1 ) ); |
| len = 64; |
| } |
| else if ( len > 0 ) |
| { |
| /* This is a very small stem; we simply align it to the |
| * pixel grid, trying to find the minimum displacement. |
| * |
| * left = pos |
| * right = pos + len |
| * left_nearest_edge = ROUND(pos) |
| * right_nearest_edge = ROUND(right) |
| * |
| * if ( ABS(left_nearest_edge - left) <= |
| * ABS(right_nearest_edge - right) ) |
| * new_pos = left |
| * else |
| * new_pos = right |
| */ |
| FT_Pos left_nearest = FT_PIX_ROUND( pos ); |
| FT_Pos right_nearest = FT_PIX_ROUND( pos + len ); |
| FT_Pos left_disp = left_nearest - pos; |
| FT_Pos right_disp = right_nearest - ( pos + len ); |
| |
| |
| if ( left_disp < 0 ) |
| left_disp = -left_disp; |
| if ( right_disp < 0 ) |
| right_disp = -right_disp; |
| if ( left_disp <= right_disp ) |
| pos = left_nearest; |
| else |
| pos = right_nearest; |
| } |
| else |
| { |
| /* this is a ghost stem; we simply round it */ |
| pos = FT_PIX_ROUND( pos ); |
| } |
| } |
| else |
| { |
| len = psh_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 + psh_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 = FT_PIX_ROUND( len ); |
| |
| 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 = FT_PIX_FLOOR( pos + ( len >> 1 ) ) + 32; |
| else |
| pos = FT_PIX_ROUND( pos + ( len >> 1 ) ); |
| |
| hint->cur_pos = pos - ( len >> 1 ); |
| hint->cur_len = len; |
| } |
| } |
| |
| psh_hint_set_fitted( hint ); |
| |
| #ifdef DEBUG_HINTER |
| if ( ps_debug_hint_func ) |
| ps_debug_hint_func( hint, dimension ); |
| #endif |
| } |
| } |
| |
| |
| #if 0 /* not used for now, experimental */ |
| |
| /* |
| * A variant to perform "light" hinting (i.e. FT_RENDER_MODE_LIGHT) |
| * of stems |
| */ |
| static void |
| psh_hint_align_light( PSH_Hint hint, |
| PSH_Globals globals, |
| FT_Int dimension, |
| PSH_Glyph glyph ) |
| { |
| PSH_Dimension dim = &globals->dimension[dimension]; |
| FT_Fixed scale = dim->scale_mult; |
| FT_Fixed delta = dim->scale_delta; |
| |
| |
| if ( !psh_hint_is_fitted( hint ) ) |
| { |
| FT_Pos pos = FT_MulFix( hint->org_pos, scale ) + delta; |
| FT_Pos len = FT_MulFix( hint->org_len, scale ); |
| |
| 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; |
| |
| psh_hint_set_fitted( hint ); |
| return; |
| } |
| |
| fit_len = len; |
| |
| 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 ( dimension == 1 ) |
| psh_blues_snap_stem( &globals->blues, |
| ADD_INT( 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: |
| { |
| PSH_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 ( !psh_hint_is_fitted( parent ) ) |
| psh_hint_align_light( parent, globals, dimension, glyph ); |
| |
| par_org_center = parent->org_pos + ( parent->org_len / 2 ); |
| par_cur_center = parent->cur_pos + ( parent->cur_len / 2 ); |
| cur_org_center = hint->org_pos + ( hint->org_len / 2 ); |
| |
| cur_delta = FT_MulFix( cur_org_center - par_org_center, scale ); |
| pos = par_cur_center + cur_delta - ( len >> 1 ); |
| } |
| |
| /* Stems less than one pixel wide are easy -- we want to |
| * make them as dark as possible, so they must fall within |
| * one pixel. If the stem is split between two pixels |
| * then snap the edge that is nearer to the pixel boundary |
| * to the pixel boundary. |
| */ |
| if ( len <= 64 ) |
| { |
| if ( ( pos + len + 63 ) / 64 != pos / 64 + 1 ) |
| pos += psh_hint_snap_stem_side_delta ( pos, len ); |
| } |
| |
| /* Position stems other to minimize the amount of mid-grays. |
| * There are, in general, two positions that do this, |
| * illustrated as A) and B) below. |
| * |
| * + + + + |
| * |
| * A) |--------------------------------| |
| * B) |--------------------------------| |
| * C) |--------------------------------| |
| * |
| * Position A) (split the excess stem equally) should be better |
| * for stems of width N + f where f < 0.5. |
| * |
| * Position B) (split the deficiency equally) should be better |
| * for stems of width N + f where f > 0.5. |
| * |
| * It turns out though that minimizing the total number of lit |
| * pixels is also important, so position C), with one edge |
| * aligned with a pixel boundary is actually preferable |
| * to A). There are also more possible positions for C) than |
| * for A) or B), so it involves less distortion of the overall |
| * character shape. |
| */ |
| else /* len > 64 */ |
| { |
| FT_Fixed frac_len = len & 63; |
| FT_Fixed center = pos + ( len >> 1 ); |
| FT_Fixed delta_a, delta_b; |
| |
| |
| if ( ( len / 64 ) & 1 ) |
| { |
| delta_a = FT_PIX_FLOOR( center ) + 32 - center; |
| delta_b = FT_PIX_ROUND( center ) - center; |
| } |
| else |
| { |
| delta_a = FT_PIX_ROUND( center ) - center; |
| delta_b = FT_PIX_FLOOR( center ) + 32 - center; |
| } |
| |
| /* We choose between B) and C) above based on the amount |
| * of fractional stem width; for small amounts, choose |
| * C) always, for large amounts, B) always, and inbetween, |
| * pick whichever one involves less stem movement. |
| */ |
| if ( frac_len < 32 ) |
| { |
| pos += psh_hint_snap_stem_side_delta ( pos, len ); |
| } |
| else if ( frac_len < 48 ) |
| { |
| FT_Fixed side_delta = psh_hint_snap_stem_side_delta ( pos, |
| len ); |
| |
| if ( FT_ABS( side_delta ) < FT_ABS( delta_b ) ) |
| pos += side_delta; |
| else |
| pos += delta_b; |
| } |
| else |
| { |
| pos += delta_b; |
| } |
| } |
| |
| hint->cur_pos = pos; |
| } |
| } /* switch */ |
| |
| psh_hint_set_fitted( hint ); |
| |
| #ifdef DEBUG_HINTER |
| if ( ps_debug_hint_func ) |
| ps_debug_hint_func( hint, dimension ); |
| #endif |
| } |
| } |
| |
| #endif /* 0 */ |
| |
| |
| static void |
| psh_hint_table_align_hints( PSH_Hint_Table table, |
| PSH_Globals globals, |
| FT_Int dimension, |
| PSH_Glyph glyph ) |
| { |
| PSH_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 ) |
| { |
| ps_simple_scale( table, scale, delta, dimension ); |
| return; |
| } |
| |
| if ( ps_debug_no_horz_hints && dimension == 1 ) |
| { |
| ps_simple_scale( table, scale, delta, dimension ); |
| return; |
| } |
| |
| #endif /* DEBUG_HINTER */ |
| |
| hint = table->hints; |
| count = table->max_hints; |
| |
| for ( ; count > 0; count--, hint++ ) |
| psh_hint_align( hint, globals, dimension, glyph ); |
| } |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** POINTS INTERPOLATION ROUTINES *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| #define xxDEBUG_ZONES |
| |
| |
| #ifdef DEBUG_ZONES |
| |
| #include FT_CONFIG_STANDARD_LIBRARY_H |
| |
| static void |
| psh_print_zone( PSH_Zone zone ) |
| { |
| printf( "zone [scale,delta,min,max] = [%.5f,%.2f,%d,%d]\n", |
| zone->scale / 65536.0, |
| zone->delta / 64.0, |
| zone->min, |
| zone->max ); |
| } |
| |
| #endif /* DEBUG_ZONES */ |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** HINTER GLYPH MANAGEMENT *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| #define psh_corner_is_flat ft_corner_is_flat |
| #define psh_corner_orientation ft_corner_orientation |
| |
| |
| #ifdef COMPUTE_INFLEXS |
| |
| /* compute all inflex points in a given glyph */ |
| static void |
| psh_glyph_compute_inflections( PSH_Glyph glyph ) |
| { |
| FT_UInt n; |
| |
| |
| for ( n = 0; n < glyph->num_contours; n++ ) |
| { |
| PSH_Point first, start, end, before, after; |
| FT_Pos in_x, in_y, out_x, out_y; |
| FT_Int orient_prev, orient_cur; |
| 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; |
| |
| in_x = end->org_u - start->org_u; |
| in_y = end->org_v - start->org_v; |
| |
| } while ( in_x == 0 && in_y == 0 ); |
| |
| /* extend the segment start whenever possible */ |
| before = start; |
| do |
| { |
| do |
| { |
| start = before; |
| before = before->prev; |
| if ( before == first ) |
| goto Skip; |
| |
| out_x = start->org_u - before->org_u; |
| out_y = start->org_v - before->org_v; |
| |
| } while ( out_x == 0 && out_y == 0 ); |
| |
| orient_prev = psh_corner_orientation( in_x, in_y, out_x, out_y ); |
| |
| } while ( orient_prev == 0 ); |
| |
| first = start; |
| in_x = out_x; |
| in_y = out_y; |
| |
| /* 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; |
| |
| out_x = after->org_u - end->org_u; |
| out_y = after->org_v - end->org_v; |
| |
| } while ( out_x == 0 && out_y == 0 ); |
| |
| orient_cur = psh_corner_orientation( in_x, in_y, out_x, out_y ); |
| |
| } while ( orient_cur == 0 ); |
| |
| if ( ( orient_cur ^ orient_prev ) < 0 ) |
| { |
| do |
| { |
| psh_point_set_inflex( start ); |
| start = start->next; |
| } |
| while ( start != end ); |
| |
| psh_point_set_inflex( start ); |
| } |
| |
| start = end; |
| end = after; |
| orient_prev = orient_cur; |
| in_x = out_x; |
| in_y = out_y; |
| |
| } while ( !finished ); |
| |
| Skip: |
| ; |
| } |
| } |
| |
| #endif /* COMPUTE_INFLEXS */ |
| |
| |
| static void |
| psh_glyph_done( PSH_Glyph glyph ) |
| { |
| FT_Memory memory = glyph->memory; |
| |
| |
| psh_hint_table_done( &glyph->hint_tables[1], memory ); |
| psh_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 = NULL; |
| } |
| |
| |
| static PSH_Dir |
| psh_compute_dir( FT_Pos dx, |
| FT_Pos dy ) |
| { |
| FT_Pos ax, ay; |
| PSH_Dir result = PSH_DIR_NONE; |
| |
| |
| ax = FT_ABS( dx ); |
| ay = FT_ABS( dy ); |
| |
| if ( ay * 12 < ax ) |
| { |
| /* |dy| <<< |dx| means a near-horizontal segment */ |
| result = ( dx >= 0 ) ? PSH_DIR_RIGHT : PSH_DIR_LEFT; |
| } |
| else if ( ax * 12 < ay ) |
| { |
| /* |dx| <<< |dy| means a near-vertical segment */ |
| result = ( dy >= 0 ) ? PSH_DIR_UP : PSH_DIR_DOWN; |
| } |
| |
| return result; |
| } |
| |
| |
| /* load outline point coordinates into hinter glyph */ |
| static void |
| psh_glyph_load_points( PSH_Glyph glyph, |
| FT_Int dimension ) |
| { |
| FT_Vector* vec = glyph->outline->points; |
| PSH_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 |
| psh_glyph_save_points( PSH_Glyph glyph, |
| FT_Int dimension ) |
| { |
| FT_UInt n; |
| PSH_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 ( psh_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 |
| psh_glyph_init( PSH_Glyph glyph, |
| FT_Outline* outline, |
| PS_Hints ps_hints, |
| PSH_Globals globals ) |
| { |
| FT_Error error; |
| FT_Memory memory; |
| |
| |
| /* clear all fields */ |
| FT_ZERO( glyph ); |
| |
| memory = 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 = (FT_UInt)outline->n_points; |
| glyph->num_contours = (FT_UInt)outline->n_contours; |
| |
| { |
| FT_UInt first = 0, next, n; |
| PSH_Point points = glyph->points; |
| PSH_Contour contour = glyph->contours; |
| |
| |
| for ( n = 0; n < glyph->num_contours; n++ ) |
| { |
| FT_UInt count; |
| PSH_Point point; |
| |
| |
| next = (FT_UInt)outline->contours[n] + 1; |
| count = next - first; |
| |
| contour->start = points + first; |
| contour->count = 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; |
| } |
| } |
| |
| { |
| PSH_Point points = glyph->points; |
| PSH_Point point = points; |
| FT_Vector* vec = outline->points; |
| FT_UInt n; |
| |
| |
| for ( n = 0; n < glyph->num_points; n++, point++ ) |
| { |
| FT_Int n_prev = (FT_Int)( point->prev - points ); |
| FT_Int n_next = (FT_Int)( point->next - points ); |
| FT_Pos dxi, dyi, dxo, dyo; |
| |
| |
| if ( !( outline->tags[n] & FT_CURVE_TAG_ON ) ) |
| point->flags = PSH_POINT_OFF; |
| |
| dxi = vec[n].x - vec[n_prev].x; |
| dyi = vec[n].y - vec[n_prev].y; |
| |
| point->dir_in = psh_compute_dir( dxi, dyi ); |
| |
| dxo = vec[n_next].x - vec[n].x; |
| dyo = vec[n_next].y - vec[n].y; |
| |
| point->dir_out = psh_compute_dir( dxo, dyo ); |
| |
| /* detect smooth points */ |
| if ( point->flags & PSH_POINT_OFF ) |
| point->flags |= PSH_POINT_SMOOTH; |
| |
| else if ( point->dir_in == point->dir_out ) |
| { |
| if ( point->dir_out != PSH_DIR_NONE || |
| psh_corner_is_flat( dxi, dyi, dxo, dyo ) ) |
| point->flags |= PSH_POINT_SMOOTH; |
| } |
| } |
| } |
| |
| glyph->outline = outline; |
| glyph->globals = globals; |
| |
| #ifdef COMPUTE_INFLEXS |
| psh_glyph_load_points( glyph, 0 ); |
| psh_glyph_compute_inflections( glyph ); |
| #endif /* COMPUTE_INFLEXS */ |
| |
| /* now deal with hints tables */ |
| error = psh_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 = psh_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 |
| psh_glyph_compute_extrema( PSH_Glyph glyph ) |
| { |
| FT_UInt n; |
| |
| |
| /* first of all, compute all local extrema */ |
| for ( n = 0; n < glyph->num_contours; n++ ) |
| { |
| PSH_Point first = glyph->contours[n].start; |
| PSH_Point point, before, after; |
| |
| |
| if ( glyph->contours[n].count == 0 ) |
| continue; |
| |
| point = first; |
| before = 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 |
| { |
| psh_point_set_extremum( point ); |
| point = point->next; |
| |
| } while ( point != after ); |
| } |
| } |
| |
| before = after->prev; |
| point = after; |
| |
| } /* for */ |
| |
| Next: |
| ; |
| } |
| |
| /* for each extremum, determine its direction along the */ |
| /* orthogonal axis */ |
| for ( n = 0; n < glyph->num_points; n++ ) |
| { |
| PSH_Point point, before, after; |
| |
| |
| point = &glyph->points[n]; |
| before = point; |
| after = point; |
| |
| if ( psh_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 ) |
| { |
| psh_point_set_positive( point ); |
| } |
| else if ( before->org_v > point->org_v && |
| after->org_v < point->org_v ) |
| { |
| psh_point_set_negative( point ); |
| } |
| |
| Skip: |
| ; |
| } |
| } |
| |
| |
| /* the min and max are based on contour orientation and fill rule */ |
| static void |
| psh_hint_table_find_strong_points( PSH_Hint_Table table, |
| PSH_Point point, |
| FT_UInt count, |
| FT_Int threshold, |
| PSH_Dir major_dir ) |
| { |
| PSH_Hint* sort = table->sort; |
| FT_UInt num_hints = table->num_hints; |
| |
| |
| for ( ; count > 0; count--, point++ ) |
| { |
| PSH_Dir point_dir; |
| FT_Pos org_u = point->org_u; |
| |
| |
| if ( psh_point_is_strong( point ) ) |
| continue; |
| |
| point_dir = |
| (PSH_Dir)( ( point->dir_in | point->dir_out ) & major_dir ); |
| |
| if ( point_dir & ( PSH_DIR_DOWN | PSH_DIR_RIGHT ) ) |
| { |
| FT_UInt nn; |
| |
| |
| for ( nn = 0; nn < num_hints; nn++ ) |
| { |
| PSH_Hint hint = sort[nn]; |
| FT_Pos d = org_u - hint->org_pos; |
| |
| |
| if ( d < threshold && -d < threshold ) |
| { |
| psh_point_set_strong( point ); |
| point->flags2 |= PSH_POINT_EDGE_MIN; |
| point->hint = hint; |
| break; |
| } |
| } |
| } |
| else if ( point_dir & ( PSH_DIR_UP | PSH_DIR_LEFT ) ) |
| { |
| FT_UInt nn; |
| |
| |
| for ( nn = 0; nn < num_hints; nn++ ) |
| { |
| PSH_Hint hint = sort[nn]; |
| FT_Pos d = org_u - hint->org_pos - hint->org_len; |
| |
| |
| if ( d < threshold && -d < threshold ) |
| { |
| psh_point_set_strong( point ); |
| point->flags2 |= PSH_POINT_EDGE_MAX; |
| point->hint = hint; |
| break; |
| } |
| } |
| } |
| |
| #if 1 |
| else if ( psh_point_is_extremum( point ) ) |
| { |
| /* treat extrema as special cases for stem edge alignment */ |
| FT_UInt nn, min_flag, max_flag; |
| |
| |
| if ( major_dir == PSH_DIR_HORIZONTAL ) |
| { |
| min_flag = PSH_POINT_POSITIVE; |
| max_flag = PSH_POINT_NEGATIVE; |
| } |
| else |
| { |
| min_flag = PSH_POINT_NEGATIVE; |
| max_flag = PSH_POINT_POSITIVE; |
| } |
| |
| if ( point->flags2 & min_flag ) |
| { |
| for ( nn = 0; nn < num_hints; nn++ ) |
| { |
| PSH_Hint hint = sort[nn]; |
| FT_Pos d = org_u - hint->org_pos; |
| |
| |
| if ( d < threshold && -d < threshold ) |
| { |
| point->flags2 |= PSH_POINT_EDGE_MIN; |
| point->hint = hint; |
| psh_point_set_strong( point ); |
| break; |
| } |
| } |
| } |
| else if ( point->flags2 & max_flag ) |
| { |
| for ( nn = 0; nn < num_hints; nn++ ) |
| { |
| PSH_Hint hint = sort[nn]; |
| FT_Pos d = org_u - hint->org_pos - hint->org_len; |
| |
| |
| if ( d < threshold && -d < threshold ) |
| { |
| point->flags2 |= PSH_POINT_EDGE_MAX; |
| point->hint = hint; |
| psh_point_set_strong( point ); |
| break; |
| } |
| } |
| } |
| |
| if ( !point->hint ) |
| { |
| for ( nn = 0; nn < num_hints; nn++ ) |
| { |
| PSH_Hint hint = sort[nn]; |
| |
| |
| if ( org_u >= hint->org_pos && |
| org_u <= ADD_INT( hint->org_pos, hint->org_len ) ) |
| { |
| point->hint = hint; |
| break; |
| } |
| } |
| } |
| } |
| |
| #endif /* 1 */ |
| } |
| } |
| |
| |
| /* the accepted shift for strong points in fractional pixels */ |
| #define PSH_STRONG_THRESHOLD 32 |
| |
| /* the maximum shift value in font units */ |
| #define PSH_STRONG_THRESHOLD_MAXIMUM 30 |
| |
| |
| /* find strong points in a glyph */ |
| static void |
| psh_glyph_find_strong_points( PSH_Glyph glyph, |
| FT_Int dimension ) |
| { |
| /* a point is `strong' if it is located on a stem edge and */ |
| /* has an `in' or `out' tangent parallel to the hint's direction */ |
| |
| PSH_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; |
| PSH_Dir major_dir = ( dimension == 0 ) ? PSH_DIR_VERTICAL |
| : PSH_DIR_HORIZONTAL; |
| PSH_Dimension dim = &glyph->globals->dimension[dimension]; |
| FT_Fixed scale = dim->scale_mult; |
| FT_Int threshold; |
| |
| |
| threshold = (FT_Int)FT_DivFix( PSH_STRONG_THRESHOLD, scale ); |
| if ( threshold > PSH_STRONG_THRESHOLD_MAXIMUM ) |
| threshold = PSH_STRONG_THRESHOLD_MAXIMUM; |
| |
| /* process secondary hints to `selected' points */ |
| if ( num_masks > 1 && glyph->num_points > 0 ) |
| { |
| /* the `endchar' op can reduce the number of points */ |
| first = mask->end_point > glyph->num_points |
| ? glyph->num_points |
| : mask->end_point; |
| mask++; |
| for ( ; num_masks > 1; num_masks--, mask++ ) |
| { |
| FT_UInt next = FT_MIN( mask->end_point, glyph->num_points ); |
| |
| |
| if ( next > first ) |
| { |
| FT_UInt count = next - first; |
| PSH_Point point = glyph->points + first; |
| |
| |
| psh_hint_table_activate_mask( table, mask ); |
| |
| psh_hint_table_find_strong_points( table, point, count, |
| threshold, major_dir ); |
| } |
| first = next; |
| } |
| } |
| |
| /* process primary hints for all points */ |
| if ( num_masks == 1 ) |
| { |
| FT_UInt count = glyph->num_points; |
| PSH_Point point = glyph->points; |
| |
| |
| psh_hint_table_activate_mask( table, table->hint_masks->masks ); |
| |
| psh_hint_table_find_strong_points( table, point, count, |
| threshold, major_dir ); |
| } |
| |
| /* now, certain points may have been attached to a hint and */ |
| /* not marked as strong; update their flags then */ |
| { |
| FT_UInt count = glyph->num_points; |
| PSH_Point point = glyph->points; |
| |
| |
| for ( ; count > 0; count--, point++ ) |
| if ( point->hint && !psh_point_is_strong( point ) ) |
| psh_point_set_strong( point ); |
| } |
| } |
| |
| |
| /* find points in a glyph which are in a blue zone and have `in' or */ |
| /* `out' tangents parallel to the horizontal axis */ |
| static void |
| psh_glyph_find_blue_points( PSH_Blues blues, |
| PSH_Glyph glyph ) |
| { |
| PSH_Blue_Table table; |
| PSH_Blue_Zone zone; |
| FT_UInt glyph_count = glyph->num_points; |
| FT_UInt blue_count; |
| PSH_Point point = glyph->points; |
| |
| |
| for ( ; glyph_count > 0; glyph_count--, point++ ) |
| { |
| FT_Pos y; |
| |
| |
| /* check tangents */ |
| if ( !( point->dir_in & PSH_DIR_HORIZONTAL ) && |
| !( point->dir_out & PSH_DIR_HORIZONTAL ) ) |
| continue; |
| |
| /* skip strong points */ |
| if ( psh_point_is_strong( point ) ) |
| continue; |
| |
| y = point->org_u; |
| |
| /* look up top zones */ |
| table = &blues->normal_top; |
| blue_count = table->count; |
| zone = table->zones; |
| |
| for ( ; blue_count > 0; blue_count--, zone++ ) |
| { |
| FT_Pos delta = y - zone->org_bottom; |
| |
| |
| if ( delta < -blues->blue_fuzz ) |
| break; |
| |
| if ( y <= zone->org_top + blues->blue_fuzz ) |
| if ( blues->no_overshoots || delta <= blues->blue_threshold ) |
| { |
| point->cur_u = zone->cur_bottom; |
| psh_point_set_strong( point ); |
| psh_point_set_fitted( point ); |
| } |
| } |
| |
| /* look up bottom zones */ |
| table = &blues->normal_bottom; |
| blue_count = table->count; |
| zone = table->zones + blue_count - 1; |
| |
| for ( ; blue_count > 0; blue_count--, zone-- ) |
| { |
| FT_Pos delta = zone->org_top - y; |
| |
| |
| if ( delta < -blues->blue_fuzz ) |
| break; |
| |
| if ( y >= zone->org_bottom - blues->blue_fuzz ) |
| if ( blues->no_overshoots || delta < blues->blue_threshold ) |
| { |
| point->cur_u = zone->cur_top; |
| psh_point_set_strong( point ); |
| psh_point_set_fitted( point ); |
| } |
| } |
| } |
| } |
| |
| |
| /* interpolate strong points with the help of hinted coordinates */ |
| static void |
| psh_glyph_interpolate_strong_points( PSH_Glyph glyph, |
| FT_Int dimension ) |
| { |
| PSH_Dimension dim = &glyph->globals->dimension[dimension]; |
| FT_Fixed scale = dim->scale_mult; |
| |
| FT_UInt count = glyph->num_points; |
| PSH_Point point = glyph->points; |
| |
| |
| for ( ; count > 0; count--, point++ ) |
| { |
| PSH_Hint hint = point->hint; |
| |
| |
| if ( hint ) |
| { |
| FT_Pos delta; |
| |
| |
| if ( psh_point_is_edge_min( point ) ) |
| point->cur_u = hint->cur_pos; |
| |
| else if ( psh_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 /* hint->org_len > 0 */ |
| point->cur_u = hint->cur_pos + |
| FT_MulDiv( delta, hint->cur_len, |
| hint->org_len ); |
| } |
| psh_point_set_fitted( point ); |
| } |
| } |
| } |
| |
| |
| #define PSH_MAX_STRONG_INTERNAL 16 |
| |
| static void |
| psh_glyph_interpolate_normal_points( PSH_Glyph glyph, |
| FT_Int dimension ) |
| { |
| |
| #if 1 |
| /* first technique: a point is strong if it is a local extremum */ |
| |
| PSH_Dimension dim = &glyph->globals->dimension[dimension]; |
| FT_Fixed scale = dim->scale_mult; |
| FT_Memory memory = glyph->memory; |
| |
| PSH_Point* strongs = NULL; |
| PSH_Point strongs_0[PSH_MAX_STRONG_INTERNAL]; |
| FT_UInt num_strongs = 0; |
| |
| PSH_Point points = glyph->points; |
| PSH_Point points_end = points + glyph->num_points; |
| PSH_Point point; |
| |
| |
| /* first count the number of strong points */ |
| for ( point = points; point < points_end; point++ ) |
| { |
| if ( psh_point_is_strong( point ) ) |
| num_strongs++; |
| } |
| |
| if ( num_strongs == 0 ) /* nothing to do here */ |
| return; |
| |
| /* allocate an array to store a list of points, */ |
| /* stored in increasing org_u order */ |
| if ( num_strongs <= PSH_MAX_STRONG_INTERNAL ) |
| strongs = strongs_0; |
| else |
| { |
| FT_Error error; |
| |
| |
| if ( FT_NEW_ARRAY( strongs, num_strongs ) ) |
| return; |
| } |
| |
| num_strongs = 0; |
| for ( point = points; point < points_end; point++ ) |
| { |
| PSH_Point* insert; |
| |
| |
| if ( !psh_point_is_strong( point ) ) |
| continue; |
| |
| for ( insert = strongs + num_strongs; insert > strongs; insert-- ) |
| { |
| if ( insert[-1]->org_u <= point->org_u ) |
| break; |
| |
| insert[0] = insert[-1]; |
| } |
| insert[0] = point; |
| num_strongs++; |
| } |
| |
| /* now try to interpolate all normal points */ |
| for ( point = points; point < points_end; point++ ) |
| { |
| if ( psh_point_is_strong( point ) ) |
| continue; |
| |
| /* sometimes, some local extrema are smooth points */ |
| if ( psh_point_is_smooth( point ) ) |
| { |
| if ( point->dir_in == PSH_DIR_NONE || |
| point->dir_in != point->dir_out ) |
| continue; |
| |
| if ( !psh_point_is_extremum( point ) && |
| !psh_point_is_inflex( point ) ) |
| continue; |
| |
| point->flags &= ~PSH_POINT_SMOOTH; |
| } |
| |
| /* find best enclosing point coordinates then interpolate */ |
| { |
| PSH_Point before, after; |
| FT_UInt nn; |
| |
| |
| for ( nn = 0; nn < num_strongs; nn++ ) |
| if ( strongs[nn]->org_u > point->org_u ) |
| break; |
| |
| if ( nn == 0 ) /* point before the first strong point */ |
| { |
| after = strongs[0]; |
| |
| point->cur_u = after->cur_u + |
| FT_MulFix( point->org_u - after->org_u, |
| scale ); |
| } |
| else |
| { |
| before = strongs[nn - 1]; |
| |
| for ( nn = num_strongs; nn > 0; nn-- ) |
| if ( strongs[nn - 1]->org_u < point->org_u ) |
| break; |
| |
| if ( nn == num_strongs ) /* point is after last strong point */ |
| { |
| before = strongs[nn - 1]; |
| |
| point->cur_u = before->cur_u + |
| FT_MulFix( point->org_u - before->org_u, |
| scale ); |
| } |
| else |
| { |
| FT_Pos u; |
| |
| |
| after = strongs[nn]; |
| |
| /* now interpolate point between before and after */ |
| u = point->org_u; |
| |
| if ( u == before->org_u ) |
| point->cur_u = before->cur_u; |
| |
| else if ( u == after->org_u ) |
| 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 ); |
| } |
| } |
| psh_point_set_fitted( point ); |
| } |
| } |
| |
| if ( strongs != strongs_0 ) |
| FT_FREE( strongs ); |
| |
| #endif /* 1 */ |
| |
| } |
| |
| |
| /* interpolate other points */ |
| static void |
| psh_glyph_interpolate_other_points( PSH_Glyph glyph, |
| FT_Int dimension ) |
| { |
| PSH_Dimension dim = &glyph->globals->dimension[dimension]; |
| FT_Fixed scale = dim->scale_mult; |
| FT_Fixed delta = dim->scale_delta; |
| PSH_Contour contour = glyph->contours; |
| FT_UInt num_contours = glyph->num_contours; |
| |
| |
| for ( ; num_contours > 0; num_contours--, contour++ ) |
| { |
| PSH_Point start = contour->start; |
| PSH_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 = NULL; |
| |
| for ( point = start; point < next; point++ ) |
| if ( psh_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 |
| { |
| /* skip consecutive fitted points */ |
| for (;;) |
| { |
| next = first->next; |
| if ( next == start ) |
| goto Next_Contour; |
| |
| if ( !psh_point_is_fitted( next ) ) |
| break; |
| |
| first = next; |
| } |
| |
| /* find next fitted point after unfitted one */ |
| for (;;) |
| { |
| next = next->next; |
| if ( psh_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 |
| ps_hints_apply( PS_Hints ps_hints, |
| FT_Outline* outline, |
| PSH_Globals globals, |
| FT_Render_Mode hint_mode ) |
| { |
| PSH_GlyphRec glyphrec; |
| PSH_Glyph glyph = &glyphrec; |
| FT_Error error; |
| #ifdef DEBUG_HINTER |
| FT_Memory memory; |
| #endif |
| FT_Int dimension; |
| |
| |
| /* something to do? */ |
| if ( outline->n_points == 0 || outline->n_contours == 0 ) |
| return FT_Err_Ok; |
| |
| #ifdef DEBUG_HINTER |
| |
| memory = globals->memory; |
| |
| if ( ps_debug_glyph ) |
| { |
| psh_glyph_done( ps_debug_glyph ); |
| FT_FREE( ps_debug_glyph ); |
| } |
| |
| if ( FT_NEW( glyph ) ) |
| return error; |
| |
| ps_debug_glyph = glyph; |
| |
| #endif /* DEBUG_HINTER */ |
| |
| error = psh_glyph_init( glyph, outline, ps_hints, globals ); |
| if ( error ) |
| goto Exit; |
| |
| /* try to optimize the y_scale so that the top of non-capital letters |
| * is aligned on a pixel boundary whenever possible |
| */ |
| { |
| PSH_Dimension dim_x = &glyph->globals->dimension[0]; |
| PSH_Dimension dim_y = &glyph->globals->dimension[1]; |
| |
| FT_Fixed x_scale = dim_x->scale_mult; |
| FT_Fixed y_scale = dim_y->scale_mult; |
| |
| FT_Fixed old_x_scale = x_scale; |
| FT_Fixed old_y_scale = y_scale; |
| |
| FT_Fixed scaled; |
| FT_Fixed fitted; |
| |
| FT_Bool rescale = FALSE; |
| |
| |
| scaled = FT_MulFix( globals->blues.normal_top.zones->org_ref, y_scale ); |
| fitted = FT_PIX_ROUND( scaled ); |
| |
| if ( fitted != 0 && scaled != fitted ) |
| { |
| rescale = TRUE; |
| |
| y_scale = FT_MulDiv( y_scale, fitted, scaled ); |
| |
| if ( fitted < scaled ) |
| x_scale -= x_scale / 50; |
| |
| psh_globals_set_scale( glyph->globals, x_scale, y_scale, 0, 0 ); |
| } |
| |
| 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 ); |
| |
| glyph->do_stem_adjust = FT_BOOL( hint_mode != FT_RENDER_MODE_LIGHT ); |
| |
| for ( dimension = 0; dimension < 2; dimension++ ) |
| { |
| /* load outline coordinates into glyph */ |
| psh_glyph_load_points( glyph, dimension ); |
| |
| /* compute local extrema */ |
| psh_glyph_compute_extrema( glyph ); |
| |
| /* compute aligned stem/hints positions */ |
| psh_hint_table_align_hints( &glyph->hint_tables[dimension], |
| glyph->globals, |
| dimension, |
| glyph ); |
| |
| /* find strong points, align them, then interpolate others */ |
| psh_glyph_find_strong_points( glyph, dimension ); |
| if ( dimension == 1 ) |
| psh_glyph_find_blue_points( &globals->blues, glyph ); |
| psh_glyph_interpolate_strong_points( glyph, dimension ); |
| psh_glyph_interpolate_normal_points( glyph, dimension ); |
| psh_glyph_interpolate_other_points( glyph, dimension ); |
| |
| /* save hinted coordinates back to outline */ |
| psh_glyph_save_points( glyph, dimension ); |
| |
| if ( rescale ) |
| psh_globals_set_scale( glyph->globals, |
| old_x_scale, old_y_scale, 0, 0 ); |
| } |
| } |
| |
| Exit: |
| |
| #ifndef DEBUG_HINTER |
| psh_glyph_done( glyph ); |
| #endif |
| |
| return error; |
| } |
| |
| |
| /* END */ |