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/****************************************************************************
*
* pfrgload.c
*
* FreeType PFR glyph loader (body).
*
* Copyright (C) 2002-2024 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 "pfrgload.h"
#include "pfrsbit.h"
#include "pfrload.h" /* for macro definitions */
#include <freetype/internal/ftdebug.h>
#include "pfrerror.h"
#undef FT_COMPONENT
#define FT_COMPONENT pfr
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** PFR GLYPH BUILDER *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
FT_LOCAL_DEF( void )
pfr_glyph_init( PFR_Glyph glyph,
FT_GlyphLoader loader )
{
FT_ZERO( glyph );
glyph->loader = loader;
FT_GlyphLoader_Rewind( loader );
}
FT_LOCAL_DEF( void )
pfr_glyph_done( PFR_Glyph glyph )
{
FT_Memory memory = glyph->loader->memory;
FT_FREE( glyph->x_control );
glyph->y_control = NULL;
glyph->max_xy_control = 0;
#if 0
glyph->num_x_control = 0;
glyph->num_y_control = 0;
#endif
FT_FREE( glyph->subs );
glyph->max_subs = 0;
glyph->num_subs = 0;
glyph->loader = NULL;
glyph->path_begun = 0;
}
/* close current contour, if any */
static void
pfr_glyph_close_contour( PFR_Glyph glyph )
{
FT_GlyphLoader loader = glyph->loader;
FT_Outline* outline = &loader->current.outline;
FT_Int last, first;
if ( !glyph->path_begun )
return;
/* compute first and last point indices in current glyph outline */
last = outline->n_points - 1;
first = 0;
if ( outline->n_contours > 0 )
first = outline->contours[outline->n_contours - 1];
/* if the last point falls on the same location as the first one */
/* we need to delete it */
if ( last > first )
{
FT_Vector* p1 = outline->points + first;
FT_Vector* p2 = outline->points + last;
if ( p1->x == p2->x && p1->y == p2->y )
{
outline->n_points--;
last--;
}
}
/* don't add empty contours */
if ( last >= first )
outline->contours[outline->n_contours++] = (FT_UShort)last;
glyph->path_begun = 0;
}
/* reset glyph to start the loading of a new glyph */
static void
pfr_glyph_start( PFR_Glyph glyph )
{
glyph->path_begun = 0;
}
static FT_Error
pfr_glyph_line_to( PFR_Glyph glyph,
FT_Vector* to )
{
FT_GlyphLoader loader = glyph->loader;
FT_Outline* outline = &loader->current.outline;
FT_Error error;
/* check that we have begun a new path */
if ( !glyph->path_begun )
{
error = FT_THROW( Invalid_Table );
FT_ERROR(( "pfr_glyph_line_to: invalid glyph data\n" ));
goto Exit;
}
error = FT_GLYPHLOADER_CHECK_POINTS( loader, 1, 0 );
if ( !error )
{
FT_Int n = outline->n_points;
outline->points[n] = *to;
outline->tags [n] = FT_CURVE_TAG_ON;
outline->n_points++;
}
Exit:
return error;
}
static FT_Error
pfr_glyph_curve_to( PFR_Glyph glyph,
FT_Vector* control1,
FT_Vector* control2,
FT_Vector* to )
{
FT_GlyphLoader loader = glyph->loader;
FT_Outline* outline = &loader->current.outline;
FT_Error error;
/* check that we have begun a new path */
if ( !glyph->path_begun )
{
error = FT_THROW( Invalid_Table );
FT_ERROR(( "pfr_glyph_line_to: invalid glyph data\n" ));
goto Exit;
}
error = FT_GLYPHLOADER_CHECK_POINTS( loader, 3, 0 );
if ( !error )
{
FT_Vector* vec = outline->points + outline->n_points;
FT_Byte* tag = outline->tags + outline->n_points;
vec[0] = *control1;
vec[1] = *control2;
vec[2] = *to;
tag[0] = FT_CURVE_TAG_CUBIC;
tag[1] = FT_CURVE_TAG_CUBIC;
tag[2] = FT_CURVE_TAG_ON;
outline->n_points += 3;
}
Exit:
return error;
}
static FT_Error
pfr_glyph_move_to( PFR_Glyph glyph,
FT_Vector* to )
{
FT_GlyphLoader loader = glyph->loader;
FT_Error error;
/* close current contour if any */
pfr_glyph_close_contour( glyph );
/* indicate that a new contour has started */
glyph->path_begun = 1;
/* check that there is space for a new contour and a new point */
error = FT_GLYPHLOADER_CHECK_POINTS( loader, 1, 1 );
if ( !error )
{
/* add new start point */
error = pfr_glyph_line_to( glyph, to );
}
return error;
}
static void
pfr_glyph_end( PFR_Glyph glyph )
{
/* close current contour if any */
pfr_glyph_close_contour( glyph );
/* merge the current glyph into the stack */
FT_GlyphLoader_Add( glyph->loader );
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** PFR GLYPH LOADER *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/* load a simple glyph */
static FT_Error
pfr_glyph_load_simple( PFR_Glyph glyph,
FT_Byte* p,
FT_Byte* limit )
{
FT_Error error = FT_Err_Ok;
FT_Memory memory = glyph->loader->memory;
FT_UInt flags, x_count, y_count, i, count, mask;
FT_Int x;
PFR_CHECK( 1 );
flags = PFR_NEXT_BYTE( p );
/* test for composite glyphs */
if ( flags & PFR_GLYPH_IS_COMPOUND )
goto Failure;
x_count = 0;
y_count = 0;
if ( flags & PFR_GLYPH_1BYTE_XYCOUNT )
{
PFR_CHECK( 1 );
count = PFR_NEXT_BYTE( p );
x_count = count & 15;
y_count = count >> 4;
}
else
{
if ( flags & PFR_GLYPH_XCOUNT )
{
PFR_CHECK( 1 );
x_count = PFR_NEXT_BYTE( p );
}
if ( flags & PFR_GLYPH_YCOUNT )
{
PFR_CHECK( 1 );
y_count = PFR_NEXT_BYTE( p );
}
}
count = x_count + y_count;
/* re-allocate array when necessary */
if ( count > glyph->max_xy_control )
{
FT_UInt new_max = FT_PAD_CEIL( count, 8 );
if ( FT_RENEW_ARRAY( glyph->x_control,
glyph->max_xy_control,
new_max ) )
goto Exit;
glyph->max_xy_control = new_max;
}
glyph->y_control = glyph->x_control + x_count;
mask = 0;
x = 0;
for ( i = 0; i < count; i++ )
{
if ( ( i & 7 ) == 0 )
{
PFR_CHECK( 1 );
mask = PFR_NEXT_BYTE( p );
}
if ( mask & 1 )
{
PFR_CHECK( 2 );
x = PFR_NEXT_SHORT( p );
}
else
{
PFR_CHECK( 1 );
x += PFR_NEXT_BYTE( p );
}
glyph->x_control[i] = x;
mask >>= 1;
}
/* XXX: we ignore the secondary stroke and edge definitions */
/* since we don't support native PFR hinting */
/* */
if ( flags & PFR_GLYPH_SINGLE_EXTRA_ITEMS )
{
error = pfr_extra_items_skip( &p, limit );
if ( error )
goto Exit;
}
pfr_glyph_start( glyph );
/* now load a simple glyph */
{
FT_Vector pos[4];
FT_Vector* cur;
pos[0].x = pos[0].y = 0;
pos[3] = pos[0];
for (;;)
{
FT_UInt format, format_low, args_format = 0, args_count, n;
/****************************************************************
* read instruction
*/
PFR_CHECK( 1 );
format = PFR_NEXT_BYTE( p );
format_low = format & 15;
switch ( format >> 4 )
{
case 0: /* end glyph */
FT_TRACE6(( "- end glyph" ));
args_count = 0;
break;
case 1: /* general line operation */
FT_TRACE6(( "- general line" ));
goto Line1;
case 4: /* move to inside contour */
FT_TRACE6(( "- move to inside" ));
goto Line1;
case 5: /* move to outside contour */
FT_TRACE6(( "- move to outside" ));
Line1:
args_format = format_low;
args_count = 1;
break;
case 2: /* horizontal line to */
FT_TRACE6(( "- horizontal line to cx.%d", format_low ));
if ( format_low >= x_count )
goto Failure;
pos[0].x = glyph->x_control[format_low];
pos[0].y = pos[3].y;
pos[3] = pos[0];
args_count = 0;
break;
case 3: /* vertical line to */
FT_TRACE6(( "- vertical line to cy.%d", format_low ));
if ( format_low >= y_count )
goto Failure;
pos[0].x = pos[3].x;
pos[0].y = glyph->y_control[format_low];
pos[3] = pos[0];
args_count = 0;
break;
case 6: /* horizontal to vertical curve */
FT_TRACE6(( "- hv curve" ));
args_format = 0xB8E;
args_count = 3;
break;
case 7: /* vertical to horizontal curve */
FT_TRACE6(( "- vh curve" ));
args_format = 0xE2B;
args_count = 3;
break;
default: /* general curve to */
FT_TRACE6(( "- general curve" ));
args_count = 4;
args_format = format_low;
}
/************************************************************
* now read arguments
*/
cur = pos;
for ( n = 0; n < args_count; n++ )
{
FT_UInt idx;
FT_Int delta;
/* read the X argument */
switch ( args_format & 3 )
{
case 0: /* 8-bit index */
PFR_CHECK( 1 );
idx = PFR_NEXT_BYTE( p );
if ( idx >= x_count )
goto Failure;
cur->x = glyph->x_control[idx];
FT_TRACE7(( " cx#%d", idx ));
break;
case 1: /* 16-bit absolute value */
PFR_CHECK( 2 );
cur->x = PFR_NEXT_SHORT( p );
FT_TRACE7(( " x.%ld", cur->x ));
break;
case 2: /* 8-bit delta */
PFR_CHECK( 1 );
delta = PFR_NEXT_INT8( p );
cur->x = pos[3].x + delta;
FT_TRACE7(( " dx.%d", delta ));
break;
default:
FT_TRACE7(( " |" ));
cur->x = pos[3].x;
}
/* read the Y argument */
switch ( ( args_format >> 2 ) & 3 )
{
case 0: /* 8-bit index */
PFR_CHECK( 1 );
idx = PFR_NEXT_BYTE( p );
if ( idx >= y_count )
goto Failure;
cur->y = glyph->y_control[idx];
FT_TRACE7(( " cy#%d", idx ));
break;
case 1: /* 16-bit absolute value */
PFR_CHECK( 2 );
cur->y = PFR_NEXT_SHORT( p );
FT_TRACE7(( " y.%ld", cur->y ));
break;
case 2: /* 8-bit delta */
PFR_CHECK( 1 );
delta = PFR_NEXT_INT8( p );
cur->y = pos[3].y + delta;
FT_TRACE7(( " dy.%d", delta ));
break;
default:
FT_TRACE7(( " -" ));
cur->y = pos[3].y;
}
/* read the additional format flag for the general curve */
if ( n == 0 && args_count == 4 )
{
PFR_CHECK( 1 );
args_format = PFR_NEXT_BYTE( p );
args_count--;
}
else
args_format >>= 4;
/* save the previous point */
pos[3] = cur[0];
cur++;
}
FT_TRACE7(( "\n" ));
/************************************************************
* finally, execute instruction
*/
switch ( format >> 4 )
{
case 0: /* end glyph => EXIT */
pfr_glyph_end( glyph );
goto Exit;
case 1: /* line operations */
case 2:
case 3:
error = pfr_glyph_line_to( glyph, pos );
goto Test_Error;
case 4: /* move to inside contour */
case 5: /* move to outside contour */
error = pfr_glyph_move_to( glyph, pos );
goto Test_Error;
default: /* curve operations */
error = pfr_glyph_curve_to( glyph, pos, pos + 1, pos + 2 );
Test_Error: /* test error condition */
if ( error )
goto Exit;
}
} /* for (;;) */
}
Exit:
return error;
Failure:
Too_Short:
error = FT_THROW( Invalid_Table );
FT_ERROR(( "pfr_glyph_load_simple: invalid glyph data\n" ));
goto Exit;
}
/* load a composite/compound glyph */
static FT_Error
pfr_glyph_load_compound( PFR_Glyph glyph,
FT_Byte* p,
FT_Byte* limit )
{
FT_Error error = FT_Err_Ok;
FT_Memory memory = glyph->loader->memory;
PFR_SubGlyph subglyph;
FT_UInt flags, i, count, org_count;
FT_Int x_pos, y_pos;
PFR_CHECK( 1 );
flags = PFR_NEXT_BYTE( p );
/* test for composite glyphs */
if ( !( flags & PFR_GLYPH_IS_COMPOUND ) )
goto Failure;
count = flags & 0x3F;
/* ignore extra items when present */
/* */
if ( flags & PFR_GLYPH_COMPOUND_EXTRA_ITEMS )
{
error = pfr_extra_items_skip( &p, limit );
if ( error )
goto Exit;
}
/* we can't rely on the FT_GlyphLoader to load sub-glyphs, because */
/* the PFR format is dumb, using direct file offsets to point to the */
/* sub-glyphs (instead of glyph indices). Sigh. */
/* */
/* For now, we load the list of sub-glyphs into a different array */
/* but this will prevent us from using the auto-hinter at its best */
/* quality. */
/* */
org_count = glyph->num_subs;
if ( org_count + count > glyph->max_subs )
{
FT_UInt new_max = ( org_count + count + 3 ) & (FT_UInt)-4;
/* we arbitrarily limit the number of subglyphs */
/* to avoid endless recursion */
if ( new_max > 64 )
{
error = FT_THROW( Invalid_Table );
FT_ERROR(( "pfr_glyph_load_compound:"
" too many compound glyphs components\n" ));
goto Exit;
}
if ( FT_RENEW_ARRAY( glyph->subs, glyph->max_subs, new_max ) )
goto Exit;
glyph->max_subs = new_max;
}
subglyph = glyph->subs + org_count;
for ( i = 0; i < count; i++, subglyph++ )
{
FT_UInt format;
x_pos = 0;
y_pos = 0;
PFR_CHECK( 1 );
format = PFR_NEXT_BYTE( p );
/* read scale when available */
subglyph->x_scale = 0x10000L;
if ( format & PFR_SUBGLYPH_XSCALE )
{
PFR_CHECK( 2 );
subglyph->x_scale = PFR_NEXT_SHORT( p ) * 16;
}
subglyph->y_scale = 0x10000L;
if ( format & PFR_SUBGLYPH_YSCALE )
{
PFR_CHECK( 2 );
subglyph->y_scale = PFR_NEXT_SHORT( p ) * 16;
}
/* read offset */
switch ( format & 3 )
{
case 1:
PFR_CHECK( 2 );
x_pos = PFR_NEXT_SHORT( p );
break;
case 2:
PFR_CHECK( 1 );
x_pos += PFR_NEXT_INT8( p );
break;
default:
;
}
switch ( ( format >> 2 ) & 3 )
{
case 1:
PFR_CHECK( 2 );
y_pos = PFR_NEXT_SHORT( p );
break;
case 2:
PFR_CHECK( 1 );
y_pos += PFR_NEXT_INT8( p );
break;
default:
;
}
subglyph->x_delta = x_pos;
subglyph->y_delta = y_pos;
/* read glyph position and size now */
if ( format & PFR_SUBGLYPH_2BYTE_SIZE )
{
PFR_CHECK( 2 );
subglyph->gps_size = PFR_NEXT_USHORT( p );
}
else
{
PFR_CHECK( 1 );
subglyph->gps_size = PFR_NEXT_BYTE( p );
}
if ( format & PFR_SUBGLYPH_3BYTE_OFFSET )
{
PFR_CHECK( 3 );
subglyph->gps_offset = PFR_NEXT_ULONG( p );
}
else
{
PFR_CHECK( 2 );
subglyph->gps_offset = PFR_NEXT_USHORT( p );
}
glyph->num_subs++;
}
Exit:
return error;
Failure:
Too_Short:
error = FT_THROW( Invalid_Table );
FT_ERROR(( "pfr_glyph_load_compound: invalid glyph data\n" ));
goto Exit;
}
static FT_Error
pfr_glyph_load_rec( PFR_Glyph glyph,
FT_Stream stream,
FT_ULong gps_offset,
FT_ULong offset,
FT_ULong size )
{
FT_Error error;
FT_Byte* p;
FT_Byte* limit;
if ( FT_STREAM_SEEK( gps_offset + offset ) ||
FT_FRAME_ENTER( size ) )
goto Exit;
p = (FT_Byte*)stream->cursor;
limit = p + size;
if ( size > 0 && *p & PFR_GLYPH_IS_COMPOUND )
{
FT_UInt n, old_count, count;
FT_GlyphLoader loader = glyph->loader;
FT_Outline* base = &loader->base.outline;
old_count = glyph->num_subs;
/* this is a compound glyph - load it */
error = pfr_glyph_load_compound( glyph, p, limit );
FT_FRAME_EXIT();
if ( error )
goto Exit;
count = glyph->num_subs - old_count;
FT_TRACE4(( "compound glyph with %d element%s (offset %lu):\n",
count,
count == 1 ? "" : "s",
offset ));
/* now, load each individual glyph */
for ( n = 0; n < count; n++ )
{
FT_Int i, old_points, num_points;
PFR_SubGlyph subglyph;
FT_TRACE4(( " subglyph %d:\n", n ));
subglyph = glyph->subs + old_count + n;
old_points = base->n_points;
error = pfr_glyph_load_rec( glyph, stream, gps_offset,
subglyph->gps_offset,
subglyph->gps_size );
if ( error )
break;
/* note that `glyph->subs' might have been re-allocated */
subglyph = glyph->subs + old_count + n;
num_points = base->n_points - old_points;
/* translate and eventually scale the new glyph points */
if ( subglyph->x_scale != 0x10000L || subglyph->y_scale != 0x10000L )
{
FT_Vector* vec = base->points + old_points;
for ( i = 0; i < num_points; i++, vec++ )
{
vec->x = FT_MulFix( vec->x, subglyph->x_scale ) +
subglyph->x_delta;
vec->y = FT_MulFix( vec->y, subglyph->y_scale ) +
subglyph->y_delta;
}
}
else
{
FT_Vector* vec = loader->base.outline.points + old_points;
for ( i = 0; i < num_points; i++, vec++ )
{
vec->x += subglyph->x_delta;
vec->y += subglyph->y_delta;
}
}
/* proceed to next sub-glyph */
}
FT_TRACE4(( "end compound glyph with %d element%s\n",
count,
count == 1 ? "" : "s" ));
}
else
{
FT_TRACE4(( "simple glyph (offset %lu)\n", offset ));
/* load a simple glyph */
error = pfr_glyph_load_simple( glyph, p, limit );
FT_FRAME_EXIT();
}
Exit:
return error;
}
FT_LOCAL_DEF( FT_Error )
pfr_glyph_load( PFR_Glyph glyph,
FT_Stream stream,
FT_ULong gps_offset,
FT_ULong offset,
FT_ULong size )
{
/* initialize glyph loader */
FT_GlyphLoader_Rewind( glyph->loader );
glyph->num_subs = 0;
/* load the glyph, recursively when needed */
return pfr_glyph_load_rec( glyph, stream, gps_offset, offset, size );
}
/* END */