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freetype/src/pshinter/pshalgo3.c

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adding Owen Taylor's patches to the Postscript hinter for testing
2002-07-03 23:00:26 +02:00
/***************************************************************************/
/* */
/* 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
extern PSH3_Hint_Table ps3_debug_hint_table = 0;
extern PSH3_HintFunc ps3_debug_hint_func = 0;
extern PSH3_Glyph ps3_debug_glyph = 0;
#endif
#undef SNAP_STEMS
#undef ONLY_ALIGN_Y
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** 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(( "%s.activate: 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(( "%s.activate: too many sorted hints! BUG!\n",
"ps.fitter" ));
}
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(( "%s.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(( "%s.activate_mask: found overlapping hints\n",
"psf.hint" ));
}
#else
count2 = 0;
#endif
if ( count2 == 0 )
{
psh3_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;
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 *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
#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
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 )
{
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 );
#ifdef SNAP_STEMS
FT_Pos fit_center;
FT_Pos fit_len;
PSH_AlignmentRec align;
/* compute fitted width/height */
fit_len = 0;
if ( hint->org_len )
{
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 ( 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 );
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 );
#if 0
if ( cur_delta >= 0 )
cur_delta = ( cur_delta + 16 ) & -64;
else
cur_delta = -( (-cur_delta + 16 ) & -64 );
#endif
pos = par_cur_center + cur_delta - ( len >> 1 );
}
/* 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
PSH_AlignmentRec align;
hint->cur_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 );
#ifdef ONLY_ALIGN_Y
else
{
hint->cur_pos = pos;
return;
}
#endif
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 - 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 );
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 += psh3_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 possibile positions for C) than
* for A) or B), so it involves less distortion of the overall
* character shape.
*/
else
{
FT_Fixed frac_len = len & 63;
FT_Fixed center = pos + ( len >> 1 );
FT_Fixed delta_a, delta_b;
if ( ( len / 64 ) & 1 )
{
delta_a = ( center & -64 ) + 32 - center;
delta_b = ( ( center + 32 ) & - 64 ) - center;
}
else
{
delta_a = ( ( center + 32 ) & - 64 ) - center;
delta_b = ( center & -64 ) + 32 - center;
}
/* We choose between B) and C) above based on the amount
* of fractinal 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 += psh3_hint_snap_stem_side_delta ( pos, len );
}
else if (frac_len < 48)
{
FT_Fixed side_delta = psh3_hint_snap_stem_side_delta ( pos, len );
if ( ABS( side_delta ) < ABS( delta_b ) )
pos += side_delta;
else
pos += delta_b;
}
else
{
pos += delta_b;
}
}
}
hint->cur_pos = pos;
}
}
#endif
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_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
hint = table->hints;
count = table->max_hints;
for ( ; count > 0; count--, hint++ )
psh3_hint_align( hint, globals, dimension );
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** POINTS INTERPOLATION ROUTINES *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
#define PSH3_ZONE_MIN -3200000
#define PSH3_ZONE_MAX +3200000
#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
#if 0
/* setup interpolation zones once the hints have been grid-fitted */
/* by the optimizer */
static void
psh3_hint_table_setup_zones( PSH3_Hint_Table table,
FT_Fixed scale,
FT_Fixed delta )
{
FT_UInt count;
PSH3_Zone zone;
PSH3_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 = PSH3_ZONE_MIN;
zone->max = PSH3_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 = PSH3_ZONE_MIN;
zone->max = hint->org_pos;
psh3_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 );
psh3_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 );
psh3_print_zone( zone );
zone++;
hint = hint2;
}
/* the last zone */
zone->scale = scale;
zone->min = hint->org_pos + hint->org_len;
zone->max = PSH3_ZONE_MAX;
zone->delta = hint->cur_pos + hint->cur_len -
FT_MulFix( zone->min, scale );
psh3_print_zone( zone );
zone++;
table->num_zones = zone - table->zones;
table->zone = table->zones;
}
#endif
#if 0
/* tune a single coordinate with the current interpolation zones */
static FT_Pos
psh3_hint_table_tune_coord( PSH3_Hint_Table table,
FT_Int coord )
{
PSH3_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;
}
#endif
#if 0
/* tune a given outline with current interpolation zones */
/* the function only works in a single dimension.. */
static void
psh3_hint_table_tune_outline( PSH3_Hint_Table table,
FT_Outline* outline,
PSH_Globals globals,
FT_Int dimension )
{
FT_UInt count, first, last;
PS_Mask_Table hint_masks = table->hint_masks;
PS_Mask mask;
PSH_Dimension dim = &globals->dimension[dimension];
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;
psh3_hint_table_activate_mask( table, mask );
psh3_hint_table_optimize( table, globals, outline, dimension );
psh3_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 = dimension ? &vec->y : &vec->x;
x = *px;
*px = psh3_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 ( dimension == 0 )
{
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;
}
}
}
#endif
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** HINTER GLYPH MANAGEMENT *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
static int
psh3_point_is_extremum( PSH3_Point point )
{
PSH3_Point before = point;
PSH3_Point after = point;
FT_Pos d_before;
FT_Pos d_after;
do
{
before = before->prev;
if ( before == point )
return 0;
d_before = before->org_u - point->org_u;
} while ( d_before == 0 );
do
{
after = after->next;
if ( after == point )
return 0;
d_after = after->org_u - point->org_u;
} while ( d_after == 0 );
return ( ( d_before > 0 && d_after > 0 ) ||
( d_before < 0 && d_after < 0 ) );
}
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;
}
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_memset( glyph, 0, 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;
/* 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;
}
/* 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->flags &= PSH3_POINT_OFF | PSH3_POINT_SMOOTH;
point->hint = 0;
if ( dimension == 0 )
point->org_u = vec->x;
else
point->org_u = vec->y;
#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->flags;
}
else
{
point->cur_y = point->cur_u;
point->flags_y = point->flags;
}
#endif
point++;
}
}
#define PSH3_STRONG_THRESHOLD 10
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;
for ( ; num_hints > 0; num_hints--, sort++ )
{
PSH3_Hint hint = sort[0];
if ( ABS( point->dir_in ) == major_dir ||
ABS( point->dir_out ) == major_dir )
{
FT_Pos d;
d = point->org_u - hint->org_pos;
if ( ABS( d ) < PSH3_STRONG_THRESHOLD )
{
Is_Strong:
psh3_point_set_strong( point );
point->hint = hint;
break;
}
d -= hint->org_len;
if ( ABS( d ) < PSH3_STRONG_THRESHOLD )
goto Is_Strong;
}
#if 1
if ( point->org_u >= hint->org_pos &&
point->org_u <= hint->org_pos + hint->org_len &&
psh3_point_is_extremum( point ) )
{
/* attach to hint, but don't mark as strong */
point->hint = hint;
break;
}
#endif
}
}
/* 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_UP : PSH3_DIR_RIGHT;
/* process secondary hints to "selected" points */
if ( num_masks > 1 )
{
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;
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 ) )
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
}
/* 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 )
{
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
error = psh3_glyph_init( glyph, outline, ps_hints, globals );
if ( error )
goto Exit;
for ( dimension = 0; dimension < 2; dimension++ )
{
/* load outline coordinates into glyph */
psh3_glyph_load_points( glyph, dimension );
/* compute aligned stem/hints positions */
psh3_hint_table_align_hints( &glyph->hint_tables[dimension],
glyph->globals,
dimension );
/* 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 */
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