1 /***************************************************************************/
5 /* TrueType and OpenType embedded bitmap support (body). */
7 /* Copyright 1996-2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 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 /***************************************************************************/
19 #include FT_INTERNAL_DEBUG_H
20 #include FT_INTERNAL_STREAM_H
21 #include FT_TRUETYPE_TAGS_H
24 * Alas, the memory-optimized sbit loader can't be used when implementing
25 * the `old internals' hack
27 #ifndef FT_CONFIG_OPTION_OLD_INTERNALS
31 #else /* FT_CONFIG_OPTION_OLD_INTERNALS */
34 #include FT_INTERNAL_DEBUG_H
35 #include FT_INTERNAL_STREAM_H
36 #include FT_TRUETYPE_TAGS_H
42 /*************************************************************************/
44 /* The macro FT_COMPONENT is used in trace mode. It is an implicit */
45 /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */
46 /* messages during execution. */
49 #define FT_COMPONENT trace_ttsbit
52 /*************************************************************************/
58 /* Blits a bitmap from an input stream into a given target. Supports */
59 /* x and y offsets as well as byte padded lines. */
62 /* target :: The target bitmap/pixmap. */
64 /* source :: The input packed bitmap data. */
66 /* line_bits :: The number of bits per line. */
68 /* byte_padded :: A flag which is true if lines are byte-padded. */
70 /* x_offset :: The horizontal offset. */
72 /* y_offset :: The vertical offset. */
75 /* IMPORTANT: The x and y offsets are relative to the top corner of */
76 /* the target bitmap (unlike the normal TrueType */
77 /* convention). A positive y offset indicates a downwards */
81 blit_sbit( FT_Bitmap* target,
87 FT_Int source_height )
97 /* first of all, compute starting write position */
98 line_incr = target->pitch;
99 line_buff = target->buffer;
102 line_buff -= line_incr * ( target->rows - 1 );
104 line_buff += ( x_offset >> 3 ) + y_offset * line_incr;
106 /***********************************************************************/
108 /* We use the extra-classic `accumulator' trick to extract the bits */
109 /* from the source byte stream. */
111 /* Namely, the variable `acc' is a 16-bit accumulator containing the */
112 /* last `loaded' bits from the input stream. The bits are shifted to */
113 /* the upmost position in `acc'. */
115 /***********************************************************************/
117 acc = 0; /* clear accumulator */
118 loaded = 0; /* no bits were loaded */
120 for ( height = source_height; height > 0; height-- )
122 FT_Byte* cur = line_buff; /* current write cursor */
123 FT_Int count = line_bits; /* # of bits to extract per line */
124 FT_Byte shift = (FT_Byte)( x_offset & 7 ); /* current write shift */
125 FT_Byte space = (FT_Byte)( 8 - shift );
128 /* first of all, read individual source bytes */
138 /* ensure that there are at least 8 bits in the accumulator */
141 acc |= (FT_UShort)((FT_UShort)*source++ << ( 8 - loaded ));
145 /* now write one byte */
146 val = (FT_Byte)( acc >> 8 );
149 cur[0] |= (FT_Byte)( val >> shift );
150 cur[1] |= (FT_Byte)( val << space );
156 acc <<= 8; /* remove bits from accumulator */
160 } while ( count >= 0 );
163 /* restore `count' to correct value */
167 /* now write remaining bits (count < 8) */
173 /* ensure that there are at least `count' bits in the accumulator */
174 if ( (FT_Int)loaded < count )
176 acc |= (FT_UShort)((FT_UShort)*source++ << ( 8 - loaded ));
180 /* now write remaining bits */
181 val = (FT_Byte)( ( (FT_Byte)( acc >> 8 ) ) & ~( 0xFF >> count ) );
182 cur[0] |= (FT_Byte)( val >> shift );
185 cur[1] |= (FT_Byte)( val << space );
191 /* now, skip to next line */
195 loaded = 0; /* clear accumulator on byte-padded lines */
198 line_buff += line_incr;
203 static const FT_Frame_Field sbit_metrics_fields[] =
206 #define FT_STRUCTURE TT_SBit_MetricsRec
209 FT_FRAME_BYTE( height ),
210 FT_FRAME_BYTE( width ),
212 FT_FRAME_CHAR( horiBearingX ),
213 FT_FRAME_CHAR( horiBearingY ),
214 FT_FRAME_BYTE( horiAdvance ),
216 FT_FRAME_CHAR( vertBearingX ),
217 FT_FRAME_CHAR( vertBearingY ),
218 FT_FRAME_BYTE( vertAdvance ),
223 /*************************************************************************/
226 /* Load_SBit_Const_Metrics */
229 /* Loads the metrics for `EBLC' index tables format 2 and 5. */
232 /* range :: The target range. */
234 /* stream :: The input stream. */
237 /* FreeType error code. 0 means success. */
240 Load_SBit_Const_Metrics( TT_SBit_Range range,
246 if ( FT_READ_ULONG( range->image_size ) )
249 return FT_STREAM_READ_FIELDS( sbit_metrics_fields, &range->metrics );
253 /*************************************************************************/
256 /* Load_SBit_Range_Codes */
259 /* Loads the range codes for `EBLC' index tables format 4 and 5. */
262 /* range :: The target range. */
264 /* stream :: The input stream. */
266 /* load_offsets :: A flag whether to load the glyph offset table. */
269 /* FreeType error code. 0 means success. */
272 Load_SBit_Range_Codes( TT_SBit_Range range,
274 FT_Bool load_offsets )
277 FT_ULong count, n, size;
278 FT_Memory memory = stream->memory;
281 if ( FT_READ_ULONG( count ) )
284 range->num_glyphs = count;
286 /* Allocate glyph offsets table if needed */
289 if ( FT_NEW_ARRAY( range->glyph_offsets, count ) )
297 /* Allocate glyph codes table and access frame */
298 if ( FT_NEW_ARRAY ( range->glyph_codes, count ) ||
299 FT_FRAME_ENTER( size ) )
302 for ( n = 0; n < count; n++ )
304 range->glyph_codes[n] = FT_GET_USHORT();
307 range->glyph_offsets[n] = (FT_ULong)range->image_offset +
318 /*************************************************************************/
321 /* Load_SBit_Range */
324 /* Loads a given `EBLC' index/range table. */
327 /* range :: The target range. */
329 /* stream :: The input stream. */
332 /* FreeType error code. 0 means success. */
335 Load_SBit_Range( TT_SBit_Range range,
339 FT_Memory memory = stream->memory;
342 switch( range->index_format )
344 case 1: /* variable metrics with 4-byte offsets */
345 case 3: /* variable metrics with 2-byte offsets */
347 FT_ULong num_glyphs, n;
349 FT_Bool large = FT_BOOL( range->index_format == 1 );
353 if ( range->last_glyph < range->first_glyph )
355 error = SFNT_Err_Invalid_File_Format;
359 num_glyphs = range->last_glyph - range->first_glyph + 1L;
360 range->num_glyphs = num_glyphs;
361 num_glyphs++; /* XXX: BEWARE - see spec */
363 size_elem = large ? 4 : 2;
365 if ( FT_NEW_ARRAY( range->glyph_offsets, num_glyphs ) ||
366 FT_FRAME_ENTER( num_glyphs * size_elem ) )
369 for ( n = 0; n < num_glyphs; n++ )
370 range->glyph_offsets[n] = (FT_ULong)( range->image_offset +
371 ( large ? FT_GET_ULONG()
372 : FT_GET_USHORT() ) );
377 case 2: /* all glyphs have identical metrics */
378 error = Load_SBit_Const_Metrics( range, stream );
382 error = Load_SBit_Range_Codes( range, stream, 1 );
386 error = Load_SBit_Const_Metrics( range, stream );
388 error = Load_SBit_Range_Codes( range, stream, 0 );
392 error = SFNT_Err_Invalid_File_Format;
400 /*************************************************************************/
403 /* tt_face_load_eblc */
406 /* Loads the table of embedded bitmap sizes for this face. */
409 /* face :: The target face object. */
411 /* stream :: The input stream. */
414 /* FreeType error code. 0 means success. */
416 FT_LOCAL_DEF( FT_Error )
417 tt_face_load_eblc( TT_Face face,
421 FT_Memory memory = stream->memory;
423 FT_ULong num_strikes;
426 static const FT_Frame_Field sbit_line_metrics_fields[] =
429 #define FT_STRUCTURE TT_SBit_LineMetricsRec
431 /* no FT_FRAME_START */
432 FT_FRAME_CHAR( ascender ),
433 FT_FRAME_CHAR( descender ),
434 FT_FRAME_BYTE( max_width ),
436 FT_FRAME_CHAR( caret_slope_numerator ),
437 FT_FRAME_CHAR( caret_slope_denominator ),
438 FT_FRAME_CHAR( caret_offset ),
440 FT_FRAME_CHAR( min_origin_SB ),
441 FT_FRAME_CHAR( min_advance_SB ),
442 FT_FRAME_CHAR( max_before_BL ),
443 FT_FRAME_CHAR( min_after_BL ),
444 FT_FRAME_CHAR( pads[0] ),
445 FT_FRAME_CHAR( pads[1] ),
449 static const FT_Frame_Field strike_start_fields[] =
452 #define FT_STRUCTURE TT_SBit_StrikeRec
454 /* no FT_FRAME_START */
455 FT_FRAME_ULONG( ranges_offset ),
457 FT_FRAME_ULONG( num_ranges ),
458 FT_FRAME_ULONG( color_ref ),
462 static const FT_Frame_Field strike_end_fields[] =
464 /* no FT_FRAME_START */
465 FT_FRAME_USHORT( start_glyph ),
466 FT_FRAME_USHORT( end_glyph ),
467 FT_FRAME_BYTE ( x_ppem ),
468 FT_FRAME_BYTE ( y_ppem ),
469 FT_FRAME_BYTE ( bit_depth ),
470 FT_FRAME_CHAR ( flags ),
475 face->num_sbit_strikes = 0;
477 /* this table is optional */
478 error = face->goto_table( face, TTAG_EBLC, stream, 0 );
480 error = face->goto_table( face, TTAG_bloc, stream, 0 );
484 table_base = FT_STREAM_POS();
485 if ( FT_FRAME_ENTER( 8L ) )
488 version = FT_GET_LONG();
489 num_strikes = FT_GET_ULONG();
493 /* check version number and strike count */
494 if ( version != 0x00020000L ||
495 num_strikes >= 0x10000L )
497 FT_ERROR(( "tt_face_load_sbit_strikes: invalid table version\n" ));
498 error = SFNT_Err_Invalid_File_Format;
503 /* allocate the strikes table */
504 if ( FT_NEW_ARRAY( face->sbit_strikes, num_strikes ) )
507 face->num_sbit_strikes = num_strikes;
509 /* now read each strike table separately */
511 TT_SBit_Strike strike = face->sbit_strikes;
512 FT_ULong count = num_strikes;
515 if ( FT_FRAME_ENTER( 48L * num_strikes ) )
520 if ( FT_STREAM_READ_FIELDS( strike_start_fields, strike ) ||
521 FT_STREAM_READ_FIELDS( sbit_line_metrics_fields, &strike->hori ) ||
522 FT_STREAM_READ_FIELDS( sbit_line_metrics_fields, &strike->vert ) ||
523 FT_STREAM_READ_FIELDS( strike_end_fields, strike ) )
533 /* allocate the index ranges for each strike table */
535 TT_SBit_Strike strike = face->sbit_strikes;
536 FT_ULong count = num_strikes;
542 FT_ULong count2 = strike->num_ranges;
545 /* read each range */
546 if ( FT_STREAM_SEEK( table_base + strike->ranges_offset ) ||
547 FT_FRAME_ENTER( strike->num_ranges * 8L ) )
550 if ( FT_NEW_ARRAY( strike->sbit_ranges, strike->num_ranges ) )
553 range = strike->sbit_ranges;
556 range->first_glyph = FT_GET_USHORT();
557 range->last_glyph = FT_GET_USHORT();
558 range->table_offset = table_base + strike->ranges_offset +
566 /* Now, read each index table */
567 count2 = strike->num_ranges;
568 range = strike->sbit_ranges;
571 /* Read the header */
572 if ( FT_STREAM_SEEK( range->table_offset ) ||
573 FT_FRAME_ENTER( 8L ) )
576 range->index_format = FT_GET_USHORT();
577 range->image_format = FT_GET_USHORT();
578 range->image_offset = FT_GET_ULONG();
582 error = Load_SBit_Range( range, stream );
600 /*************************************************************************/
603 /* tt_face_free_eblc */
606 /* Releases the embedded bitmap tables. */
609 /* face :: The target face object. */
612 tt_face_free_eblc( TT_Face face )
614 FT_Memory memory = face->root.memory;
615 TT_SBit_Strike strike = face->sbit_strikes;
616 TT_SBit_Strike strike_limit = strike + face->num_sbit_strikes;
621 for ( ; strike < strike_limit; strike++ )
623 TT_SBit_Range range = strike->sbit_ranges;
624 TT_SBit_Range range_limit = range + strike->num_ranges;
629 for ( ; range < range_limit; range++ )
631 /* release the glyph offsets and codes tables */
632 /* where appropriate */
633 FT_FREE( range->glyph_offsets );
634 FT_FREE( range->glyph_codes );
637 FT_FREE( strike->sbit_ranges );
638 strike->num_ranges = 0;
640 FT_FREE( face->sbit_strikes );
642 face->num_sbit_strikes = 0;
646 FT_LOCAL_DEF( FT_Error )
647 tt_face_set_sbit_strike( TT_Face face,
649 FT_ULong* astrike_index )
651 return FT_Match_Size( (FT_Face)face, req, 0, astrike_index );
655 FT_LOCAL_DEF( FT_Error )
656 tt_face_load_strike_metrics( TT_Face face,
657 FT_ULong strike_index,
658 FT_Size_Metrics* metrics )
660 TT_SBit_Strike strike;
663 if ( strike_index >= face->num_sbit_strikes )
664 return SFNT_Err_Invalid_Argument;
666 strike = face->sbit_strikes + strike_index;
668 metrics->x_ppem = strike->x_ppem;
669 metrics->y_ppem = strike->y_ppem;
671 metrics->ascender = strike->hori.ascender << 6;
672 metrics->descender = strike->hori.descender << 6;
674 /* XXX: Is this correct? */
675 metrics->max_advance = ( strike->hori.min_origin_SB +
676 strike->hori.max_width +
677 strike->hori.min_advance_SB ) << 6;
679 metrics->height = metrics->ascender - metrics->descender;
685 /*************************************************************************/
688 /* find_sbit_range */
691 /* Scans a given strike's ranges and return, for a given glyph */
692 /* index, the corresponding sbit range, and `EBDT' offset. */
695 /* glyph_index :: The glyph index. */
697 /* strike :: The source/current sbit strike. */
700 /* arange :: The sbit range containing the glyph index. */
702 /* aglyph_offset :: The offset of the glyph data in `EBDT' table. */
705 /* FreeType error code. 0 means the glyph index was found. */
708 find_sbit_range( FT_UInt glyph_index,
709 TT_SBit_Strike strike,
710 TT_SBit_Range *arange,
711 FT_ULong *aglyph_offset )
713 TT_SBit_RangeRec *range, *range_limit;
716 /* check whether the glyph index is within this strike's */
718 if ( glyph_index < (FT_UInt)strike->start_glyph ||
719 glyph_index > (FT_UInt)strike->end_glyph )
722 /* scan all ranges in strike */
723 range = strike->sbit_ranges;
724 range_limit = range + strike->num_ranges;
728 for ( ; range < range_limit; range++ )
730 if ( glyph_index >= (FT_UInt)range->first_glyph &&
731 glyph_index <= (FT_UInt)range->last_glyph )
733 FT_UShort delta = (FT_UShort)( glyph_index - range->first_glyph );
736 switch ( range->index_format )
740 *aglyph_offset = range->glyph_offsets[delta];
744 *aglyph_offset = range->image_offset +
745 range->image_size * delta;
754 for ( n = 0; n < range->num_glyphs; n++ )
756 if ( (FT_UInt)range->glyph_codes[n] == glyph_index )
758 if ( range->index_format == 4 )
759 *aglyph_offset = range->glyph_offsets[n];
761 *aglyph_offset = range->image_offset +
762 n * range->image_size;
774 /* return successfully! */
784 return SFNT_Err_Invalid_Argument;
788 /*************************************************************************/
791 /* tt_find_sbit_image */
794 /* Checks whether an embedded bitmap (an `sbit') exists for a given */
795 /* glyph, at a given strike. */
798 /* face :: The target face object. */
800 /* glyph_index :: The glyph index. */
802 /* strike_index :: The current strike index. */
805 /* arange :: The SBit range containing the glyph index. */
807 /* astrike :: The SBit strike containing the glyph index. */
809 /* aglyph_offset :: The offset of the glyph data in `EBDT' table. */
812 /* FreeType error code. 0 means success. Returns */
813 /* SFNT_Err_Invalid_Argument if no sbit exists for the requested */
817 tt_find_sbit_image( TT_Face face,
819 FT_ULong strike_index,
820 TT_SBit_Range *arange,
821 TT_SBit_Strike *astrike,
822 FT_ULong *aglyph_offset )
825 TT_SBit_Strike strike;
828 if ( !face->sbit_strikes ||
829 ( face->num_sbit_strikes <= strike_index ) )
832 strike = &face->sbit_strikes[strike_index];
834 error = find_sbit_range( glyph_index, strike,
835 arange, aglyph_offset );
844 /* no embedded bitmap for this glyph in face */
849 return SFNT_Err_Invalid_Argument;
853 /*************************************************************************/
856 /* tt_load_sbit_metrics */
859 /* Gets the big metrics for a given SBit. */
862 /* stream :: The input stream. */
864 /* range :: The SBit range containing the glyph. */
867 /* big_metrics :: A big SBit metrics structure for the glyph. */
870 /* FreeType error code. 0 means success. */
873 /* The stream cursor must be positioned at the glyph's offset within */
874 /* the `EBDT' table before the call. */
876 /* If the image format uses variable metrics, the stream cursor is */
877 /* positioned just after the metrics header in the `EBDT' table on */
881 tt_load_sbit_metrics( FT_Stream stream,
883 TT_SBit_Metrics metrics )
885 FT_Error error = SFNT_Err_Ok;
888 switch ( range->image_format )
893 /* variable small metrics */
895 TT_SBit_SmallMetricsRec smetrics;
897 static const FT_Frame_Field sbit_small_metrics_fields[] =
900 #define FT_STRUCTURE TT_SBit_SmallMetricsRec
903 FT_FRAME_BYTE( height ),
904 FT_FRAME_BYTE( width ),
905 FT_FRAME_CHAR( bearingX ),
906 FT_FRAME_CHAR( bearingY ),
907 FT_FRAME_BYTE( advance ),
912 /* read small metrics */
913 if ( FT_STREAM_READ_FIELDS( sbit_small_metrics_fields, &smetrics ) )
916 /* convert it to a big metrics */
917 metrics->height = smetrics.height;
918 metrics->width = smetrics.width;
919 metrics->horiBearingX = smetrics.bearingX;
920 metrics->horiBearingY = smetrics.bearingY;
921 metrics->horiAdvance = smetrics.advance;
923 /* these metrics are made up at a higher level when */
925 metrics->vertBearingX = 0;
926 metrics->vertBearingY = 0;
927 metrics->vertAdvance = 0;
934 /* variable big metrics */
935 if ( FT_STREAM_READ_FIELDS( sbit_metrics_fields, metrics ) )
940 default: /* constant metrics */
941 if ( range->index_format == 2 || range->index_format == 5 )
942 *metrics = range->metrics;
944 return SFNT_Err_Invalid_File_Format;
952 /*************************************************************************/
958 /* Crops a bitmap to its tightest bounding box, and adjusts its */
962 /* map :: The bitmap. */
964 /* metrics :: The corresponding metrics structure. */
967 crop_bitmap( FT_Bitmap* map,
968 TT_SBit_Metrics metrics )
970 /***********************************************************************/
972 /* In this situation, some bounding boxes of embedded bitmaps are too */
973 /* large. We need to crop it to a reasonable size. */
979 /* | * | ------> | * | */
983 /* --------- ----- */
985 /***********************************************************************/
992 /***********************************************************************/
994 /* first of all, check the top-most lines of the bitmap, and remove */
995 /* them if they're empty. */
998 line = (FT_Byte*)map->buffer;
1000 line_len = map->pitch;
1003 for ( count = 0; count < rows; count++ )
1005 FT_Byte* cur = line;
1006 FT_Byte* limit = line + line_len;
1009 for ( ; cur < limit; cur++ )
1013 /* the current line was empty - skip to next one */
1018 /* check that we have at least one filled line */
1019 if ( count >= rows )
1022 /* now, crop the empty upper lines */
1025 line = (FT_Byte*)map->buffer;
1027 FT_MEM_MOVE( line, line + count * line_len,
1028 ( rows - count ) * line_len );
1030 metrics->height = (FT_Byte)( metrics->height - count );
1031 metrics->horiBearingY = (FT_Char)( metrics->horiBearingY - count );
1032 metrics->vertBearingY = (FT_Char)( metrics->vertBearingY - count );
1039 /***********************************************************************/
1041 /* second, crop the lower lines */
1044 line = (FT_Byte*)map->buffer + ( rows - 1 ) * line_len;
1046 for ( count = 0; count < rows; count++ )
1048 FT_Byte* cur = line;
1049 FT_Byte* limit = line + line_len;
1052 for ( ; cur < limit; cur++ )
1056 /* the current line was empty - skip to previous one */
1063 metrics->height = (FT_Byte)( metrics->height - count );
1069 /***********************************************************************/
1071 /* third, get rid of the space on the left side of the glyph */
1078 line = (FT_Byte*)map->buffer;
1079 limit = line + rows * line_len;
1081 for ( ; line < limit; line += line_len )
1082 if ( line[0] & 0x80 )
1085 /* shift the whole glyph one pixel to the left */
1086 line = (FT_Byte*)map->buffer;
1087 limit = line + rows * line_len;
1089 for ( ; line < limit; line += line_len )
1091 FT_Int n, width = map->width;
1093 FT_Byte* cur = line;
1096 old = (FT_Byte)(cur[0] << 1);
1097 for ( n = 8; n < width; n += 8 )
1103 cur[0] = (FT_Byte)( old | ( val >> 7 ) );
1104 old = (FT_Byte)( val << 1 );
1111 metrics->horiBearingX++;
1112 metrics->vertBearingX++;
1115 } while ( map->width > 0 );
1119 /***********************************************************************/
1121 /* finally, crop the bitmap width to get rid of the space on the right */
1122 /* side of the glyph. */
1126 FT_Int right = map->width - 1;
1131 line = (FT_Byte*)map->buffer + ( right >> 3 );
1132 limit = line + rows * line_len;
1133 mask = (FT_Byte)( 0x80 >> ( right & 7 ) );
1135 for ( ; line < limit; line += line_len )
1136 if ( line[0] & mask )
1139 /* crop the whole glyph to the right */
1143 } while ( map->width > 0 );
1146 /* all right, the bitmap was cropped */
1153 map->pixel_mode = FT_PIXEL_MODE_MONO;
1158 Load_SBit_Single( FT_Bitmap* map,
1162 FT_UShort image_format,
1163 TT_SBit_Metrics metrics,
1169 /* check that the source bitmap fits into the target pixmap */
1170 if ( x_offset < 0 || x_offset + metrics->width > map->width ||
1171 y_offset < 0 || y_offset + metrics->height > map->rows )
1173 error = SFNT_Err_Invalid_Argument;
1179 FT_Int glyph_width = metrics->width;
1180 FT_Int glyph_height = metrics->height;
1182 FT_Int line_bits = pix_bits * glyph_width;
1183 FT_Bool pad_bytes = 0;
1186 /* compute size of glyph image */
1187 switch ( image_format )
1189 case 1: /* byte-padded formats */
1198 line_length = ( glyph_width + 7 ) >> 3;
1201 line_length = ( glyph_width + 3 ) >> 2;
1204 line_length = ( glyph_width + 1 ) >> 1;
1207 line_length = glyph_width;
1210 glyph_size = glyph_height * line_length;
1218 line_bits = glyph_width * pix_bits;
1219 glyph_size = ( glyph_height * line_bits + 7 ) >> 3;
1222 default: /* invalid format */
1223 return SFNT_Err_Invalid_File_Format;
1226 /* Now read data and draw glyph into target pixmap */
1227 if ( FT_FRAME_ENTER( glyph_size ) )
1230 /* don't forget to multiply `x_offset' by `map->pix_bits' as */
1231 /* the sbit blitter doesn't make a difference between pixmap */
1233 blit_sbit( map, (FT_Byte*)stream->cursor, line_bits, pad_bytes,
1234 x_offset * pix_bits, y_offset, metrics->height );
1245 Load_SBit_Image( TT_SBit_Strike strike,
1246 TT_SBit_Range range,
1248 FT_ULong glyph_offset,
1253 TT_SBit_Metrics metrics,
1256 FT_Memory memory = stream->memory;
1257 FT_Bitmap* map = &slot->bitmap;
1261 /* place stream at beginning of glyph data and read metrics */
1262 if ( FT_STREAM_SEEK( ebdt_pos + glyph_offset ) )
1265 error = tt_load_sbit_metrics( stream, range, metrics );
1269 /* This function is recursive. At the top-level call, we */
1270 /* compute the dimensions of the higher-level glyph to */
1271 /* allocate the final pixmap buffer. */
1277 map->width = metrics->width;
1278 map->rows = metrics->height;
1280 switch ( strike->bit_depth )
1283 map->pixel_mode = FT_PIXEL_MODE_MONO;
1284 map->pitch = ( map->width + 7 ) >> 3;
1288 map->pixel_mode = FT_PIXEL_MODE_GRAY2;
1289 map->pitch = ( map->width + 3 ) >> 2;
1293 map->pixel_mode = FT_PIXEL_MODE_GRAY4;
1294 map->pitch = ( map->width + 1 ) >> 1;
1298 map->pixel_mode = FT_PIXEL_MODE_GRAY;
1299 map->pitch = map->width;
1303 return SFNT_Err_Invalid_File_Format;
1306 size = map->rows * map->pitch;
1308 /* check that there is no empty image */
1310 goto Exit; /* exit successfully! */
1312 error = ft_glyphslot_alloc_bitmap( slot, size );
1317 switch ( range->image_format )
1319 case 1: /* single sbit image - load it */
1324 return Load_SBit_Single( map, x_offset, y_offset, strike->bit_depth,
1325 range->image_format, metrics, stream );
1327 case 8: /* compound format */
1328 if ( FT_STREAM_SKIP( 1L ) )
1330 error = SFNT_Err_Invalid_Stream_Skip;
1338 default: /* invalid image format */
1339 return SFNT_Err_Invalid_File_Format;
1342 /* All right, we have a compound format. First of all, read */
1343 /* the array of elements. */
1345 TT_SBit_Component components;
1346 TT_SBit_Component comp;
1347 FT_UShort num_components, count;
1350 if ( FT_READ_USHORT( num_components ) ||
1351 FT_NEW_ARRAY( components, num_components ) )
1354 count = num_components;
1356 if ( FT_FRAME_ENTER( 4L * num_components ) )
1359 for ( comp = components; count > 0; count--, comp++ )
1361 comp->glyph_code = FT_GET_USHORT();
1362 comp->x_offset = FT_GET_CHAR();
1363 comp->y_offset = FT_GET_CHAR();
1368 /* Now recursively load each element glyph */
1369 count = num_components;
1371 for ( ; count > 0; count--, comp++ )
1373 TT_SBit_Range elem_range;
1374 TT_SBit_MetricsRec elem_metrics;
1375 FT_ULong elem_offset;
1378 /* find the range for this element */
1379 error = find_sbit_range( comp->glyph_code,
1386 /* now load the element, recursively */
1387 error = Load_SBit_Image( strike,
1392 x_offset + comp->x_offset,
1393 y_offset + comp->y_offset,
1402 FT_FREE( components );
1410 /*************************************************************************/
1413 /* tt_face_load_sbit_image */
1416 /* Loads a given glyph sbit image from the font resource. This also */
1417 /* returns its metrics. */
1420 /* face :: The target face object. */
1422 /* strike_index :: The current strike index. */
1424 /* glyph_index :: The current glyph index. */
1426 /* load_flags :: The glyph load flags (the code checks for the flag */
1427 /* FT_LOAD_CROP_BITMAP). */
1429 /* stream :: The input stream. */
1432 /* map :: The target pixmap. */
1434 /* metrics :: A big sbit metrics structure for the glyph image. */
1437 /* FreeType error code. 0 means success. Returns an error if no */
1438 /* glyph sbit exists for the index. */
1441 /* The `map.buffer' field is always freed before the glyph is loaded. */
1443 FT_LOCAL_DEF( FT_Error )
1444 tt_face_load_sbit_image( TT_Face face,
1445 FT_ULong strike_index,
1446 FT_UInt glyph_index,
1450 TT_SBit_MetricsRec *metrics )
1453 FT_ULong ebdt_pos, glyph_offset;
1455 TT_SBit_Strike strike;
1456 TT_SBit_Range range;
1459 /* Check whether there is a glyph sbit for the current index */
1460 error = tt_find_sbit_image( face, glyph_index, strike_index,
1461 &range, &strike, &glyph_offset );
1465 /* now, find the location of the `EBDT' table in */
1467 error = face->goto_table( face, TTAG_EBDT, stream, 0 );
1469 error = face->goto_table( face, TTAG_bdat, stream, 0 );
1473 ebdt_pos = FT_STREAM_POS();
1475 error = Load_SBit_Image( strike, range, ebdt_pos, glyph_offset,
1476 face->root.glyph, 0, 0, stream, metrics, 0 );
1480 /* setup vertical metrics if needed */
1481 if ( strike->flags & 1 )
1483 /* in case of a horizontal strike only */
1487 advance = strike->hori.ascender - strike->hori.descender;
1489 /* some heuristic values */
1491 metrics->vertBearingX = (FT_Char)(-metrics->width / 2 );
1492 metrics->vertBearingY = (FT_Char)( ( advance - metrics->height ) / 2 );
1493 metrics->vertAdvance = (FT_Char)( advance * 12 / 10 );
1496 /* Crop the bitmap now, unless specified otherwise */
1497 if ( load_flags & FT_LOAD_CROP_BITMAP )
1498 crop_bitmap( map, metrics );
1504 #endif /* FT_CONFIG_OPTION_OLD_INTERNALS */