1
/***************************************************************************/
5
/* TrueType and OpenType embedded bitmap support (body). */
7
/* Copyright 1996-2001, 2002, 2003, 2004 by */
8
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
10
/* This file is part of the FreeType project, and may only be used, */
11
/* modified, and distributed under the terms of the FreeType project */
12
/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
13
/* this file you indicate that you have read the license and */
14
/* understand and accept it fully. */
16
/***************************************************************************/
20
#include FT_INTERNAL_DEBUG_H
21
#include FT_INTERNAL_STREAM_H
22
#include FT_TRUETYPE_TAGS_H
28
/*************************************************************************/
30
/* The macro FT_COMPONENT is used in trace mode. It is an implicit */
31
/* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */
32
/* messages during execution. */
35
#define FT_COMPONENT trace_ttsbit
38
/*************************************************************************/
44
/* Blits a bitmap from an input stream into a given target. Supports */
45
/* x and y offsets as well as byte padded lines. */
48
/* target :: The target bitmap/pixmap. */
50
/* source :: The input packed bitmap data. */
52
/* line_bits :: The number of bits per line. */
54
/* byte_padded :: A flag which is true if lines are byte-padded. */
56
/* x_offset :: The horizontal offset. */
58
/* y_offset :: The vertical offset. */
61
/* IMPORTANT: The x and y offsets are relative to the top corner of */
62
/* the target bitmap (unlike the normal TrueType */
63
/* convention). A positive y offset indicates a downwards */
67
blit_sbit( FT_Bitmap* target,
82
/* first of all, compute starting write position */
83
line_incr = target->pitch;
84
line_buff = target->buffer;
87
line_buff -= line_incr * ( target->rows - 1 );
89
line_buff += ( x_offset >> 3 ) + y_offset * line_incr;
91
/***********************************************************************/
93
/* We use the extra-classic `accumulator' trick to extract the bits */
94
/* from the source byte stream. */
96
/* Namely, the variable `acc' is a 16-bit accumulator containing the */
97
/* last `loaded' bits from the input stream. The bits are shifted to */
98
/* the upmost position in `acc'. */
100
/***********************************************************************/
102
acc = 0; /* clear accumulator */
103
loaded = 0; /* no bits were loaded */
105
for ( height = target->rows; height > 0; height-- )
107
FT_Byte* cur = line_buff; /* current write cursor */
108
FT_Int count = line_bits; /* # of bits to extract per line */
109
FT_Byte shift = (FT_Byte)( x_offset & 7 ); /* current write shift */
110
FT_Byte space = (FT_Byte)( 8 - shift );
113
/* first of all, read individual source bytes */
123
/* ensure that there are at least 8 bits in the accumulator */
126
acc |= (FT_UShort)((FT_UShort)*source++ << ( 8 - loaded ));
130
/* now write one byte */
131
val = (FT_Byte)( acc >> 8 );
134
cur[0] |= (FT_Byte)( val >> shift );
135
cur[1] |= (FT_Byte)( val << space );
141
acc <<= 8; /* remove bits from accumulator */
145
} while ( count >= 0 );
148
/* restore `count' to correct value */
152
/* now write remaining bits (count < 8) */
158
/* ensure that there are at least `count' bits in the accumulator */
159
if ( (FT_Int)loaded < count )
161
acc |= (FT_UShort)((FT_UShort)*source++ << ( 8 - loaded ));
165
/* now write remaining bits */
166
val = (FT_Byte)( ( (FT_Byte)( acc >> 8 ) ) & ~( 0xFF >> count ) );
167
cur[0] |= (FT_Byte)( val >> shift );
170
cur[1] |= (FT_Byte)( val << space );
176
/* now, skip to next line */
180
loaded = 0; /* clear accumulator on byte-padded lines */
183
line_buff += line_incr;
188
const FT_Frame_Field sbit_metrics_fields[] =
191
#define FT_STRUCTURE TT_SBit_MetricsRec
194
FT_FRAME_BYTE( height ),
195
FT_FRAME_BYTE( width ),
197
FT_FRAME_CHAR( horiBearingX ),
198
FT_FRAME_CHAR( horiBearingY ),
199
FT_FRAME_BYTE( horiAdvance ),
201
FT_FRAME_CHAR( vertBearingX ),
202
FT_FRAME_CHAR( vertBearingY ),
203
FT_FRAME_BYTE( vertAdvance ),
208
/*************************************************************************/
211
/* TT_Load_SBit_Const_Metrics */
214
/* Loads the metrics for `EBLC' index tables format 2 and 5. */
217
/* range :: The target range. */
219
/* stream :: The input stream. */
222
/* FreeType error code. 0 means success. */
225
Load_SBit_Const_Metrics( TT_SBit_Range range,
231
if ( FT_READ_ULONG( range->image_size ) )
234
return FT_STREAM_READ_FIELDS( sbit_metrics_fields, &range->metrics );
238
/*************************************************************************/
241
/* TT_Load_SBit_Range_Codes */
244
/* Loads the range codes for `EBLC' index tables format 4 and 5. */
247
/* range :: The target range. */
249
/* stream :: The input stream. */
251
/* load_offsets :: A flag whether to load the glyph offset table. */
254
/* FreeType error code. 0 means success. */
257
Load_SBit_Range_Codes( TT_SBit_Range range,
259
FT_Bool load_offsets )
262
FT_ULong count, n, size;
263
FT_Memory memory = stream->memory;
266
if ( FT_READ_ULONG( count ) )
269
range->num_glyphs = count;
271
/* Allocate glyph offsets table if needed */
274
if ( FT_NEW_ARRAY( range->glyph_offsets, count ) )
282
/* Allocate glyph codes table and access frame */
283
if ( FT_NEW_ARRAY ( range->glyph_codes, count ) ||
284
FT_FRAME_ENTER( size ) )
287
for ( n = 0; n < count; n++ )
289
range->glyph_codes[n] = FT_GET_USHORT();
292
range->glyph_offsets[n] = (FT_ULong)range->image_offset +
303
/*************************************************************************/
306
/* TT_Load_SBit_Range */
309
/* Loads a given `EBLC' index/range table. */
312
/* range :: The target range. */
314
/* stream :: The input stream. */
317
/* FreeType error code. 0 means success. */
320
Load_SBit_Range( TT_SBit_Range range,
324
FT_Memory memory = stream->memory;
327
switch( range->index_format )
329
case 1: /* variable metrics with 4-byte offsets */
330
case 3: /* variable metrics with 2-byte offsets */
332
FT_ULong num_glyphs, n;
334
FT_Bool large = FT_BOOL( range->index_format == 1 );
337
num_glyphs = range->last_glyph - range->first_glyph + 1L;
338
range->num_glyphs = num_glyphs;
339
num_glyphs++; /* XXX: BEWARE - see spec */
341
size_elem = large ? 4 : 2;
343
if ( FT_NEW_ARRAY( range->glyph_offsets, num_glyphs ) ||
344
FT_FRAME_ENTER( num_glyphs * size_elem ) )
347
for ( n = 0; n < num_glyphs; n++ )
348
range->glyph_offsets[n] = (FT_ULong)( range->image_offset +
349
( large ? FT_GET_ULONG()
350
: FT_GET_USHORT() ) );
355
case 2: /* all glyphs have identical metrics */
356
error = Load_SBit_Const_Metrics( range, stream );
360
error = Load_SBit_Range_Codes( range, stream, 1 );
364
error = Load_SBit_Const_Metrics( range, stream ) ||
365
Load_SBit_Range_Codes( range, stream, 0 );
369
error = SFNT_Err_Invalid_File_Format;
377
/*************************************************************************/
380
/* tt_face_load_sbit_strikes */
383
/* Loads the table of embedded bitmap sizes for this face. */
386
/* face :: The target face object. */
388
/* stream :: The input stream. */
391
/* FreeType error code. 0 means success. */
393
FT_LOCAL_DEF( FT_Error )
394
tt_face_load_sbit_strikes( TT_Face face,
398
FT_Memory memory = stream->memory;
400
FT_ULong num_strikes;
403
const FT_Frame_Field sbit_line_metrics_fields[] =
406
#define FT_STRUCTURE TT_SBit_LineMetricsRec
408
/* no FT_FRAME_START */
409
FT_FRAME_CHAR( ascender ),
410
FT_FRAME_CHAR( descender ),
411
FT_FRAME_BYTE( max_width ),
413
FT_FRAME_CHAR( caret_slope_numerator ),
414
FT_FRAME_CHAR( caret_slope_denominator ),
415
FT_FRAME_CHAR( caret_offset ),
417
FT_FRAME_CHAR( min_origin_SB ),
418
FT_FRAME_CHAR( min_advance_SB ),
419
FT_FRAME_CHAR( max_before_BL ),
420
FT_FRAME_CHAR( min_after_BL ),
421
FT_FRAME_CHAR( pads[0] ),
422
FT_FRAME_CHAR( pads[1] ),
426
const FT_Frame_Field strike_start_fields[] =
429
#define FT_STRUCTURE TT_SBit_StrikeRec
431
/* no FT_FRAME_START */
432
FT_FRAME_ULONG( ranges_offset ),
434
FT_FRAME_ULONG( num_ranges ),
435
FT_FRAME_ULONG( color_ref ),
439
const FT_Frame_Field strike_end_fields[] =
441
/* no FT_FRAME_START */
442
FT_FRAME_USHORT( start_glyph ),
443
FT_FRAME_USHORT( end_glyph ),
444
FT_FRAME_BYTE ( x_ppem ),
445
FT_FRAME_BYTE ( y_ppem ),
446
FT_FRAME_BYTE ( bit_depth ),
447
FT_FRAME_CHAR ( flags ),
452
face->num_sbit_strikes = 0;
454
/* this table is optional */
455
error = face->goto_table( face, TTAG_EBLC, stream, 0 );
457
error = face->goto_table( face, TTAG_bloc, stream, 0 );
461
table_base = FT_STREAM_POS();
462
if ( FT_FRAME_ENTER( 8L ) )
465
version = FT_GET_LONG();
466
num_strikes = FT_GET_ULONG();
470
/* check version number and strike count */
471
if ( version != 0x00020000L ||
472
num_strikes >= 0x10000L )
474
FT_ERROR(( "tt_face_load_sbit_strikes: invalid table version!\n" ));
475
error = SFNT_Err_Invalid_File_Format;
480
/* allocate the strikes table */
481
if ( FT_NEW_ARRAY( face->sbit_strikes, num_strikes ) )
484
face->num_sbit_strikes = num_strikes;
486
/* now read each strike table separately */
488
TT_SBit_Strike strike = face->sbit_strikes;
489
FT_ULong count = num_strikes;
492
if ( FT_FRAME_ENTER( 48L * num_strikes ) )
497
if ( FT_STREAM_READ_FIELDS( strike_start_fields, strike ) ||
498
FT_STREAM_READ_FIELDS( sbit_line_metrics_fields, &strike->hori ) ||
499
FT_STREAM_READ_FIELDS( sbit_line_metrics_fields, &strike->vert ) ||
500
FT_STREAM_READ_FIELDS( strike_end_fields, strike ) )
510
/* allocate the index ranges for each strike table */
512
TT_SBit_Strike strike = face->sbit_strikes;
513
FT_ULong count = num_strikes;
519
FT_ULong count2 = strike->num_ranges;
522
if ( FT_NEW_ARRAY( strike->sbit_ranges, strike->num_ranges ) )
525
/* read each range */
526
if ( FT_STREAM_SEEK( table_base + strike->ranges_offset ) ||
527
FT_FRAME_ENTER( strike->num_ranges * 8L ) )
530
range = strike->sbit_ranges;
533
range->first_glyph = FT_GET_USHORT();
534
range->last_glyph = FT_GET_USHORT();
535
range->table_offset = table_base + strike->ranges_offset +
543
/* Now, read each index table */
544
count2 = strike->num_ranges;
545
range = strike->sbit_ranges;
548
/* Read the header */
549
if ( FT_STREAM_SEEK( range->table_offset ) ||
550
FT_FRAME_ENTER( 8L ) )
553
range->index_format = FT_GET_USHORT();
554
range->image_format = FT_GET_USHORT();
555
range->image_offset = FT_GET_ULONG();
559
error = Load_SBit_Range( range, stream );
577
/*************************************************************************/
580
/* tt_face_free_sbit_strikes */
583
/* Releases the embedded bitmap tables. */
586
/* face :: The target face object. */
589
tt_face_free_sbit_strikes( TT_Face face )
591
FT_Memory memory = face->root.memory;
592
TT_SBit_Strike strike = face->sbit_strikes;
593
TT_SBit_Strike strike_limit = strike + face->num_sbit_strikes;
598
for ( ; strike < strike_limit; strike++ )
600
TT_SBit_Range range = strike->sbit_ranges;
601
TT_SBit_Range range_limit = range + strike->num_ranges;
606
for ( ; range < range_limit; range++ )
608
/* release the glyph offsets and codes tables */
609
/* where appropriate */
610
FT_FREE( range->glyph_offsets );
611
FT_FREE( range->glyph_codes );
614
FT_FREE( strike->sbit_ranges );
615
strike->num_ranges = 0;
617
FT_FREE( face->sbit_strikes );
619
face->num_sbit_strikes = 0;
623
FT_LOCAL_DEF( FT_Error )
624
tt_face_set_sbit_strike( TT_Face face,
627
FT_ULong *astrike_index )
633
y_ppem < 1 || y_ppem > 255 )
634
return SFNT_Err_Invalid_PPem;
636
for ( i = 0; i < face->num_sbit_strikes; i++ )
638
if ( ( (FT_UInt)face->sbit_strikes[i].y_ppem == y_ppem ) &&
640
( (FT_UInt)face->sbit_strikes[i].x_ppem == x_ppem ) ) )
647
return SFNT_Err_Invalid_PPem;
651
/*************************************************************************/
654
/* find_sbit_range */
657
/* Scans a given strike's ranges and return, for a given glyph */
658
/* index, the corresponding sbit range, and `EBDT' offset. */
661
/* glyph_index :: The glyph index. */
663
/* strike :: The source/current sbit strike. */
666
/* arange :: The sbit range containing the glyph index. */
668
/* aglyph_offset :: The offset of the glyph data in `EBDT' table. */
671
/* FreeType error code. 0 means the glyph index was found. */
674
find_sbit_range( FT_UInt glyph_index,
675
TT_SBit_Strike strike,
676
TT_SBit_Range *arange,
677
FT_ULong *aglyph_offset )
679
TT_SBit_RangeRec *range, *range_limit;
682
/* check whether the glyph index is within this strike's */
684
if ( glyph_index < (FT_UInt)strike->start_glyph ||
685
glyph_index > (FT_UInt)strike->end_glyph )
688
/* scan all ranges in strike */
689
range = strike->sbit_ranges;
690
range_limit = range + strike->num_ranges;
694
for ( ; range < range_limit; range++ )
696
if ( glyph_index >= (FT_UInt)range->first_glyph &&
697
glyph_index <= (FT_UInt)range->last_glyph )
699
FT_UShort delta = (FT_UShort)( glyph_index - range->first_glyph );
702
switch ( range->index_format )
706
*aglyph_offset = range->glyph_offsets[delta];
710
*aglyph_offset = range->image_offset +
711
range->image_size * delta;
720
for ( n = 0; n < range->num_glyphs; n++ )
722
if ( (FT_UInt)range->glyph_codes[n] == glyph_index )
724
if ( range->index_format == 4 )
725
*aglyph_offset = range->glyph_offsets[n];
727
*aglyph_offset = range->image_offset +
728
n * range->image_size;
740
/* return successfully! */
750
return SFNT_Err_Invalid_Argument;
754
/*************************************************************************/
757
/* tt_find_sbit_image */
760
/* Checks whether an embedded bitmap (an `sbit') exists for a given */
761
/* glyph, at a given strike. */
764
/* face :: The target face object. */
766
/* glyph_index :: The glyph index. */
768
/* strike_index :: The current strike index. */
771
/* arange :: The SBit range containing the glyph index. */
773
/* astrike :: The SBit strike containing the glyph index. */
775
/* aglyph_offset :: The offset of the glyph data in `EBDT' table. */
778
/* FreeType error code. 0 means success. Returns */
779
/* SFNT_Err_Invalid_Argument if no sbit exists for the requested */
783
tt_find_sbit_image( TT_Face face,
785
FT_ULong strike_index,
786
TT_SBit_Range *arange,
787
TT_SBit_Strike *astrike,
788
FT_ULong *aglyph_offset )
791
TT_SBit_Strike strike;
794
if ( !face->sbit_strikes ||
795
( face->num_sbit_strikes <= strike_index ) )
798
strike = &face->sbit_strikes[strike_index];
800
error = find_sbit_range( glyph_index, strike,
801
arange, aglyph_offset );
810
/* no embedded bitmap for this glyph in face */
815
return SFNT_Err_Invalid_Argument;
819
/*************************************************************************/
822
/* tt_load_sbit_metrics */
825
/* Gets the big metrics for a given SBit. */
828
/* stream :: The input stream. */
830
/* range :: The SBit range containing the glyph. */
833
/* big_metrics :: A big SBit metrics structure for the glyph. */
836
/* FreeType error code. 0 means success. */
839
/* The stream cursor must be positioned at the glyph's offset within */
840
/* the `EBDT' table before the call. */
842
/* If the image format uses variable metrics, the stream cursor is */
843
/* positioned just after the metrics header in the `EBDT' table on */
847
tt_load_sbit_metrics( FT_Stream stream,
849
TT_SBit_Metrics metrics )
851
FT_Error error = SFNT_Err_Ok;
854
switch ( range->image_format )
859
/* variable small metrics */
861
TT_SBit_SmallMetricsRec smetrics;
863
const FT_Frame_Field sbit_small_metrics_fields[] =
866
#define FT_STRUCTURE TT_SBit_SmallMetricsRec
869
FT_FRAME_BYTE( height ),
870
FT_FRAME_BYTE( width ),
871
FT_FRAME_CHAR( bearingX ),
872
FT_FRAME_CHAR( bearingY ),
873
FT_FRAME_BYTE( advance ),
878
/* read small metrics */
879
if ( FT_STREAM_READ_FIELDS( sbit_small_metrics_fields, &smetrics ) )
882
/* convert it to a big metrics */
883
metrics->height = smetrics.height;
884
metrics->width = smetrics.width;
885
metrics->horiBearingX = smetrics.bearingX;
886
metrics->horiBearingY = smetrics.bearingY;
887
metrics->horiAdvance = smetrics.advance;
889
/* these metrics are made up at a higher level when */
891
metrics->vertBearingX = 0;
892
metrics->vertBearingY = 0;
893
metrics->vertAdvance = 0;
900
/* variable big metrics */
901
if ( FT_STREAM_READ_FIELDS( sbit_metrics_fields, metrics ) )
906
default: /* constant metrics */
907
if ( range->index_format == 2 || range->index_format == 5 )
908
*metrics = range->metrics;
910
return SFNT_Err_Invalid_File_Format;
918
/*************************************************************************/
924
/* Crops a bitmap to its tightest bounding box, and adjusts its */
928
/* map :: The bitmap. */
930
/* metrics :: The corresponding metrics structure. */
933
crop_bitmap( FT_Bitmap* map,
934
TT_SBit_Metrics metrics )
936
/***********************************************************************/
938
/* In this situation, some bounding boxes of embedded bitmaps are too */
939
/* large. We need to crop it to a reasonable size. */
945
/* | * | ------> | * | */
949
/* --------- ----- */
951
/***********************************************************************/
958
/***********************************************************************/
960
/* first of all, check the top-most lines of the bitmap, and remove */
961
/* them if they're empty. */
964
line = (FT_Byte*)map->buffer;
966
line_len = map->pitch;
969
for ( count = 0; count < rows; count++ )
972
FT_Byte* limit = line + line_len;
975
for ( ; cur < limit; cur++ )
979
/* the current line was empty - skip to next one */
984
/* check that we have at least one filled line */
988
/* now, crop the empty upper lines */
991
line = (FT_Byte*)map->buffer;
993
FT_MEM_MOVE( line, line + count * line_len,
994
( rows - count ) * line_len );
996
metrics->height = (FT_Byte)( metrics->height - count );
997
metrics->horiBearingY = (FT_Char)( metrics->horiBearingY - count );
998
metrics->vertBearingY = (FT_Char)( metrics->vertBearingY - count );
1005
/***********************************************************************/
1007
/* second, crop the lower lines */
1010
line = (FT_Byte*)map->buffer + ( rows - 1 ) * line_len;
1012
for ( count = 0; count < rows; count++ )
1014
FT_Byte* cur = line;
1015
FT_Byte* limit = line + line_len;
1018
for ( ; cur < limit; cur++ )
1022
/* the current line was empty - skip to previous one */
1029
metrics->height = (FT_Byte)( metrics->height - count );
1035
/***********************************************************************/
1037
/* third, get rid of the space on the left side of the glyph */
1044
line = (FT_Byte*)map->buffer;
1045
limit = line + rows * line_len;
1047
for ( ; line < limit; line += line_len )
1048
if ( line[0] & 0x80 )
1051
/* shift the whole glyph one pixel to the left */
1052
line = (FT_Byte*)map->buffer;
1053
limit = line + rows * line_len;
1055
for ( ; line < limit; line += line_len )
1057
FT_Int n, width = map->width;
1059
FT_Byte* cur = line;
1062
old = (FT_Byte)(cur[0] << 1);
1063
for ( n = 8; n < width; n += 8 )
1069
cur[0] = (FT_Byte)( old | ( val >> 7 ) );
1070
old = (FT_Byte)( val << 1 );
1077
metrics->horiBearingX++;
1078
metrics->vertBearingX++;
1081
} while ( map->width > 0 );
1085
/***********************************************************************/
1087
/* finally, crop the bitmap width to get rid of the space on the right */
1088
/* side of the glyph. */
1092
FT_Int right = map->width - 1;
1097
line = (FT_Byte*)map->buffer + ( right >> 3 );
1098
limit = line + rows * line_len;
1099
mask = (FT_Byte)( 0x80 >> ( right & 7 ) );
1101
for ( ; line < limit; line += line_len )
1102
if ( line[0] & mask )
1105
/* crop the whole glyph to the right */
1109
} while ( map->width > 0 );
1112
/* all right, the bitmap was cropped */
1119
map->pixel_mode = FT_PIXEL_MODE_MONO;
1124
Load_SBit_Single( FT_Bitmap* map,
1128
FT_UShort image_format,
1129
TT_SBit_Metrics metrics,
1135
/* check that the source bitmap fits into the target pixmap */
1136
if ( x_offset < 0 || x_offset + metrics->width > map->width ||
1137
y_offset < 0 || y_offset + metrics->height > map->rows )
1139
error = SFNT_Err_Invalid_Argument;
1145
FT_Int glyph_width = metrics->width;
1146
FT_Int glyph_height = metrics->height;
1148
FT_Int line_bits = pix_bits * glyph_width;
1149
FT_Bool pad_bytes = 0;
1152
/* compute size of glyph image */
1153
switch ( image_format )
1155
case 1: /* byte-padded formats */
1164
line_length = ( glyph_width + 7 ) >> 3;
1167
line_length = ( glyph_width + 3 ) >> 2;
1170
line_length = ( glyph_width + 1 ) >> 1;
1173
line_length = glyph_width;
1176
glyph_size = glyph_height * line_length;
1184
line_bits = glyph_width * pix_bits;
1185
glyph_size = ( glyph_height * line_bits + 7 ) >> 3;
1188
default: /* invalid format */
1189
return SFNT_Err_Invalid_File_Format;
1192
/* Now read data and draw glyph into target pixmap */
1193
if ( FT_FRAME_ENTER( glyph_size ) )
1196
/* don't forget to multiply `x_offset' by `map->pix_bits' as */
1197
/* the sbit blitter doesn't make a difference between pixmap */
1199
blit_sbit( map, (FT_Byte*)stream->cursor, line_bits, pad_bytes,
1200
x_offset * pix_bits, y_offset );
1211
Load_SBit_Image( TT_SBit_Strike strike,
1212
TT_SBit_Range range,
1214
FT_ULong glyph_offset,
1219
TT_SBit_Metrics metrics,
1222
FT_Memory memory = stream->memory;
1223
FT_Bitmap* map = &slot->bitmap;
1227
/* place stream at beginning of glyph data and read metrics */
1228
if ( FT_STREAM_SEEK( ebdt_pos + glyph_offset ) )
1231
error = tt_load_sbit_metrics( stream, range, metrics );
1235
/* This function is recursive. At the top-level call, we */
1236
/* compute the dimensions of the higher-level glyph to */
1237
/* allocate the final pixmap buffer. */
1243
map->width = metrics->width;
1244
map->rows = metrics->height;
1246
switch ( strike->bit_depth )
1249
map->pixel_mode = FT_PIXEL_MODE_MONO;
1250
map->pitch = ( map->width + 7 ) >> 3;
1254
map->pixel_mode = FT_PIXEL_MODE_GRAY2;
1255
map->pitch = ( map->width + 3 ) >> 2;
1259
map->pixel_mode = FT_PIXEL_MODE_GRAY4;
1260
map->pitch = ( map->width + 1 ) >> 1;
1264
map->pixel_mode = FT_PIXEL_MODE_GRAY;
1265
map->pitch = map->width;
1269
return SFNT_Err_Invalid_File_Format;
1272
size = map->rows * map->pitch;
1274
/* check that there is no empty image */
1276
goto Exit; /* exit successfully! */
1278
error = ft_glyphslot_alloc_bitmap( slot, size );
1283
switch ( range->image_format )
1285
case 1: /* single sbit image - load it */
1290
return Load_SBit_Single( map, x_offset, y_offset, strike->bit_depth,
1291
range->image_format, metrics, stream );
1293
case 8: /* compound format */
1294
FT_Stream_Skip( stream, 1L );
1300
default: /* invalid image format */
1301
return SFNT_Err_Invalid_File_Format;
1304
/* All right, we have a compound format. First of all, read */
1305
/* the array of elements. */
1307
TT_SBit_Component components;
1308
TT_SBit_Component comp;
1309
FT_UShort num_components, count;
1312
if ( FT_READ_USHORT( num_components ) ||
1313
FT_NEW_ARRAY( components, num_components ) )
1316
count = num_components;
1318
if ( FT_FRAME_ENTER( 4L * num_components ) )
1321
for ( comp = components; count > 0; count--, comp++ )
1323
comp->glyph_code = FT_GET_USHORT();
1324
comp->x_offset = FT_GET_CHAR();
1325
comp->y_offset = FT_GET_CHAR();
1330
/* Now recursively load each element glyph */
1331
count = num_components;
1333
for ( ; count > 0; count--, comp++ )
1335
TT_SBit_Range elem_range;
1336
TT_SBit_MetricsRec elem_metrics;
1337
FT_ULong elem_offset;
1340
/* find the range for this element */
1341
error = find_sbit_range( comp->glyph_code,
1348
/* now load the element, recursively */
1349
error = Load_SBit_Image( strike,
1354
x_offset + comp->x_offset,
1355
y_offset + comp->y_offset,
1364
FT_FREE( components );
1372
/*************************************************************************/
1375
/* tt_face_load_sbit_image */
1378
/* Loads a given glyph sbit image from the font resource. This also */
1379
/* returns its metrics. */
1382
/* face :: The target face object. */
1384
/* strike_index :: The current strike index. */
1386
/* glyph_index :: The current glyph index. */
1388
/* load_flags :: The glyph load flags (the code checks for the flag */
1389
/* FT_LOAD_CROP_BITMAP). */
1391
/* stream :: The input stream. */
1394
/* map :: The target pixmap. */
1396
/* metrics :: A big sbit metrics structure for the glyph image. */
1399
/* FreeType error code. 0 means success. Returns an error if no */
1400
/* glyph sbit exists for the index. */
1403
/* The `map.buffer' field is always freed before the glyph is loaded. */
1405
FT_LOCAL_DEF( FT_Error )
1406
tt_face_load_sbit_image( TT_Face face,
1407
FT_ULong strike_index,
1408
FT_UInt glyph_index,
1412
TT_SBit_MetricsRec *metrics )
1415
FT_ULong ebdt_pos, glyph_offset;
1417
TT_SBit_Strike strike;
1418
TT_SBit_Range range;
1421
/* Check whether there is a glyph sbit for the current index */
1422
error = tt_find_sbit_image( face, glyph_index, strike_index,
1423
&range, &strike, &glyph_offset );
1427
/* now, find the location of the `EBDT' table in */
1429
error = face->goto_table( face, TTAG_EBDT, stream, 0 );
1431
error = face->goto_table( face, TTAG_bdat, stream, 0 );
1435
ebdt_pos = FT_STREAM_POS();
1437
error = Load_SBit_Image( strike, range, ebdt_pos, glyph_offset,
1438
face->root.glyph, 0, 0, stream, metrics, 0 );
1442
/* setup vertical metrics if needed */
1443
if ( strike->flags & 1 )
1445
/* in case of a horizontal strike only */
1449
advance = strike->hori.ascender - strike->hori.descender;
1451
/* some heuristic values */
1453
metrics->vertBearingX = (FT_Char)(-metrics->width / 2 );
1454
metrics->vertBearingY = (FT_Char)( advance / 10 );
1455
metrics->vertAdvance = (FT_Char)( advance * 12 / 10 );
1458
/* Crop the bitmap now, unless specified otherwise */
1459
if ( load_flags & FT_LOAD_CROP_BITMAP )
1460
crop_bitmap( map, metrics );