| /***************************************************************************/ |
| /* */ |
| /* ttsbit.c */ |
| /* */ |
| /* TrueType and OpenType embedded bitmap support (body). */ |
| /* */ |
| /* Copyright 1996-2001, 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_DEBUG_H |
| #include FT_INTERNAL_STREAM_H |
| #include FT_TRUETYPE_TAGS_H |
| #include "ttsbit.h" |
| |
| #include "sferrors.h" |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* The macro FT_COMPONENT is used in trace mode. It is an implicit */ |
| /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */ |
| /* messages during execution. */ |
| /* */ |
| #undef FT_COMPONENT |
| #define FT_COMPONENT trace_ttsbit |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* blit_sbit */ |
| /* */ |
| /* <Description> */ |
| /* Blits a bitmap from an input stream into a given target. Supports */ |
| /* x and y offsets as well as byte padded lines. */ |
| /* */ |
| /* <Input> */ |
| /* target :: The target bitmap/pixmap. */ |
| /* */ |
| /* source :: The input packed bitmap data. */ |
| /* */ |
| /* line_bits :: The number of bits per line. */ |
| /* */ |
| /* byte_padded :: A flag which is true if lines are byte-padded. */ |
| /* */ |
| /* x_offset :: The horizontal offset. */ |
| /* */ |
| /* y_offset :: The vertical offset. */ |
| /* */ |
| /* <Note> */ |
| /* IMPORTANT: The x and y offsets are relative to the top corner of */ |
| /* the target bitmap (unlike the normal TrueType */ |
| /* convention). A positive y offset indicates a downwards */ |
| /* direction! */ |
| /* */ |
| static void |
| blit_sbit( FT_Bitmap* target, |
| FT_Byte* source, |
| FT_Int line_bits, |
| FT_Bool byte_padded, |
| FT_Int x_offset, |
| FT_Int y_offset ) |
| { |
| FT_Byte* line_buff; |
| FT_Int line_incr; |
| FT_Int height; |
| |
| FT_UShort acc; |
| FT_UInt loaded; |
| |
| |
| /* first of all, compute starting write position */ |
| line_incr = target->pitch; |
| line_buff = target->buffer; |
| |
| if ( line_incr < 0 ) |
| line_buff -= line_incr * ( target->rows - 1 ); |
| |
| line_buff += ( x_offset >> 3 ) + y_offset * line_incr; |
| |
| /***********************************************************************/ |
| /* */ |
| /* We use the extra-classic `accumulator' trick to extract the bits */ |
| /* from the source byte stream. */ |
| /* */ |
| /* Namely, the variable `acc' is a 16-bit accumulator containing the */ |
| /* last `loaded' bits from the input stream. The bits are shifted to */ |
| /* the upmost position in `acc'. */ |
| /* */ |
| /***********************************************************************/ |
| |
| acc = 0; /* clear accumulator */ |
| loaded = 0; /* no bits were loaded */ |
| |
| for ( height = target->rows; height > 0; height-- ) |
| { |
| FT_Byte* cur = line_buff; /* current write cursor */ |
| FT_Int count = line_bits; /* # of bits to extract per line */ |
| FT_Byte shift = (FT_Byte)( x_offset & 7 ); /* current write shift */ |
| FT_Byte space = (FT_Byte)( 8 - shift ); |
| |
| |
| /* first of all, read individual source bytes */ |
| if ( count >= 8 ) |
| { |
| count -= 8; |
| { |
| do |
| { |
| FT_Byte val; |
| |
| |
| /* ensure that there are at least 8 bits in the accumulator */ |
| if ( loaded < 8 ) |
| { |
| acc |= (FT_UShort)((FT_UShort)*source++ << ( 8 - loaded )); |
| loaded += 8; |
| } |
| |
| /* now write one byte */ |
| val = (FT_Byte)( acc >> 8 ); |
| if ( shift ) |
| { |
| cur[0] |= (FT_Byte)( val >> shift ); |
| cur[1] |= (FT_Byte)( val << space ); |
| } |
| else |
| cur[0] |= val; |
| |
| cur++; |
| acc <<= 8; /* remove bits from accumulator */ |
| loaded -= 8; |
| count -= 8; |
| |
| } while ( count >= 0 ); |
| } |
| |
| /* restore `count' to correct value */ |
| count += 8; |
| } |
| |
| /* now write remaining bits (count < 8) */ |
| if ( count > 0 ) |
| { |
| FT_Byte val; |
| |
| |
| /* ensure that there are at least `count' bits in the accumulator */ |
| if ( (FT_Int)loaded < count ) |
| { |
| acc |= (FT_UShort)((FT_UShort)*source++ << ( 8 - loaded )); |
| loaded += 8; |
| } |
| |
| /* now write remaining bits */ |
| val = (FT_Byte)( ( (FT_Byte)( acc >> 8 ) ) & ~( 0xFF >> count ) ); |
| cur[0] |= (FT_Byte)( val >> shift ); |
| |
| if ( count > space ) |
| cur[1] |= (FT_Byte)( val << space ); |
| |
| acc <<= count; |
| loaded -= count; |
| } |
| |
| /* now, skip to next line */ |
| if ( byte_padded ) |
| { |
| acc = 0; |
| loaded = 0; /* clear accumulator on byte-padded lines */ |
| } |
| |
| line_buff += line_incr; |
| } |
| } |
| |
| |
| const FT_Frame_Field sbit_metrics_fields[] = |
| { |
| #undef FT_STRUCTURE |
| #define FT_STRUCTURE TT_SBit_MetricsRec |
| |
| FT_FRAME_START( 8 ), |
| FT_FRAME_BYTE( height ), |
| FT_FRAME_BYTE( width ), |
| |
| FT_FRAME_CHAR( horiBearingX ), |
| FT_FRAME_CHAR( horiBearingY ), |
| FT_FRAME_BYTE( horiAdvance ), |
| |
| FT_FRAME_CHAR( vertBearingX ), |
| FT_FRAME_CHAR( vertBearingY ), |
| FT_FRAME_BYTE( vertAdvance ), |
| FT_FRAME_END |
| }; |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* TT_Load_SBit_Const_Metrics */ |
| /* */ |
| /* <Description> */ |
| /* Loads the metrics for `EBLC' index tables format 2 and 5. */ |
| /* */ |
| /* <Input> */ |
| /* range :: The target range. */ |
| /* */ |
| /* stream :: The input stream. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. */ |
| /* */ |
| static FT_Error |
| Load_SBit_Const_Metrics( TT_SBit_Range range, |
| FT_Stream stream ) |
| { |
| FT_Error error; |
| |
| |
| if ( FT_READ_ULONG( range->image_size ) ) |
| return error; |
| |
| return FT_STREAM_READ_FIELDS( sbit_metrics_fields, &range->metrics ); |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* TT_Load_SBit_Range_Codes */ |
| /* */ |
| /* <Description> */ |
| /* Loads the range codes for `EBLC' index tables format 4 and 5. */ |
| /* */ |
| /* <Input> */ |
| /* range :: The target range. */ |
| /* */ |
| /* stream :: The input stream. */ |
| /* */ |
| /* load_offsets :: A flag whether to load the glyph offset table. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. */ |
| /* */ |
| static FT_Error |
| Load_SBit_Range_Codes( TT_SBit_Range range, |
| FT_Stream stream, |
| FT_Bool load_offsets ) |
| { |
| FT_Error error; |
| FT_ULong count, n, size; |
| FT_Memory memory = stream->memory; |
| |
| |
| if ( FT_READ_ULONG( count ) ) |
| goto Exit; |
| |
| range->num_glyphs = count; |
| |
| /* Allocate glyph offsets table if needed */ |
| if ( load_offsets ) |
| { |
| if ( FT_NEW_ARRAY( range->glyph_offsets, count ) ) |
| goto Exit; |
| |
| size = count * 4L; |
| } |
| else |
| size = count * 2L; |
| |
| /* Allocate glyph codes table and access frame */ |
| if ( FT_NEW_ARRAY ( range->glyph_codes, count ) || |
| FT_FRAME_ENTER( size ) ) |
| goto Exit; |
| |
| for ( n = 0; n < count; n++ ) |
| { |
| range->glyph_codes[n] = FT_GET_USHORT(); |
| |
| if ( load_offsets ) |
| range->glyph_offsets[n] = (FT_ULong)range->image_offset + |
| FT_GET_USHORT(); |
| } |
| |
| FT_FRAME_EXIT(); |
| |
| Exit: |
| return error; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* TT_Load_SBit_Range */ |
| /* */ |
| /* <Description> */ |
| /* Loads a given `EBLC' index/range table. */ |
| /* */ |
| /* <Input> */ |
| /* range :: The target range. */ |
| /* */ |
| /* stream :: The input stream. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. */ |
| /* */ |
| static FT_Error |
| Load_SBit_Range( TT_SBit_Range range, |
| FT_Stream stream ) |
| { |
| FT_Error error; |
| FT_Memory memory = stream->memory; |
| |
| |
| switch( range->index_format ) |
| { |
| case 1: /* variable metrics with 4-byte offsets */ |
| case 3: /* variable metrics with 2-byte offsets */ |
| { |
| FT_ULong num_glyphs, n; |
| FT_Int size_elem; |
| FT_Bool large = FT_BOOL( range->index_format == 1 ); |
| |
| |
| num_glyphs = range->last_glyph - range->first_glyph + 1L; |
| range->num_glyphs = num_glyphs; |
| num_glyphs++; /* XXX: BEWARE - see spec */ |
| |
| size_elem = large ? 4 : 2; |
| |
| if ( FT_NEW_ARRAY( range->glyph_offsets, num_glyphs ) || |
| FT_FRAME_ENTER( num_glyphs * size_elem ) ) |
| goto Exit; |
| |
| for ( n = 0; n < num_glyphs; n++ ) |
| range->glyph_offsets[n] = (FT_ULong)( range->image_offset + |
| ( large ? FT_GET_ULONG() |
| : FT_GET_USHORT() ) ); |
| FT_FRAME_EXIT(); |
| } |
| break; |
| |
| case 2: /* all glyphs have identical metrics */ |
| error = Load_SBit_Const_Metrics( range, stream ); |
| break; |
| |
| case 4: |
| error = Load_SBit_Range_Codes( range, stream, 1 ); |
| break; |
| |
| case 5: |
| error = Load_SBit_Const_Metrics( range, stream ) || |
| Load_SBit_Range_Codes( range, stream, 0 ); |
| break; |
| |
| default: |
| error = SFNT_Err_Invalid_File_Format; |
| } |
| |
| Exit: |
| return error; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* tt_face_load_sbit_strikes */ |
| /* */ |
| /* <Description> */ |
| /* Loads the table of embedded bitmap sizes for this face. */ |
| /* */ |
| /* <Input> */ |
| /* face :: The target face object. */ |
| /* */ |
| /* stream :: The input stream. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. */ |
| /* */ |
| FT_LOCAL_DEF( FT_Error ) |
| tt_face_load_sbit_strikes( TT_Face face, |
| FT_Stream stream ) |
| { |
| FT_Error error = 0; |
| FT_Memory memory = stream->memory; |
| FT_Fixed version; |
| FT_ULong num_strikes; |
| FT_ULong table_base; |
| |
| const FT_Frame_Field sbit_line_metrics_fields[] = |
| { |
| #undef FT_STRUCTURE |
| #define FT_STRUCTURE TT_SBit_LineMetricsRec |
| |
| /* no FT_FRAME_START */ |
| FT_FRAME_CHAR( ascender ), |
| FT_FRAME_CHAR( descender ), |
| FT_FRAME_BYTE( max_width ), |
| |
| FT_FRAME_CHAR( caret_slope_numerator ), |
| FT_FRAME_CHAR( caret_slope_denominator ), |
| FT_FRAME_CHAR( caret_offset ), |
| |
| FT_FRAME_CHAR( min_origin_SB ), |
| FT_FRAME_CHAR( min_advance_SB ), |
| FT_FRAME_CHAR( max_before_BL ), |
| FT_FRAME_CHAR( min_after_BL ), |
| FT_FRAME_CHAR( pads[0] ), |
| FT_FRAME_CHAR( pads[1] ), |
| FT_FRAME_END |
| }; |
| |
| const FT_Frame_Field strike_start_fields[] = |
| { |
| #undef FT_STRUCTURE |
| #define FT_STRUCTURE TT_SBit_StrikeRec |
| |
| /* no FT_FRAME_START */ |
| FT_FRAME_ULONG( ranges_offset ), |
| FT_FRAME_SKIP_LONG, |
| FT_FRAME_ULONG( num_ranges ), |
| FT_FRAME_ULONG( color_ref ), |
| FT_FRAME_END |
| }; |
| |
| const FT_Frame_Field strike_end_fields[] = |
| { |
| /* no FT_FRAME_START */ |
| FT_FRAME_USHORT( start_glyph ), |
| FT_FRAME_USHORT( end_glyph ), |
| FT_FRAME_BYTE ( x_ppem ), |
| FT_FRAME_BYTE ( y_ppem ), |
| FT_FRAME_BYTE ( bit_depth ), |
| FT_FRAME_CHAR ( flags ), |
| FT_FRAME_END |
| }; |
| |
| |
| face->num_sbit_strikes = 0; |
| |
| /* this table is optional */ |
| error = face->goto_table( face, TTAG_EBLC, stream, 0 ); |
| if ( error ) |
| error = face->goto_table( face, TTAG_bloc, stream, 0 ); |
| if ( error ) |
| goto Exit; |
| |
| table_base = FT_STREAM_POS(); |
| if ( FT_FRAME_ENTER( 8L ) ) |
| goto Exit; |
| |
| version = FT_GET_LONG(); |
| num_strikes = FT_GET_ULONG(); |
| |
| FT_FRAME_EXIT(); |
| |
| /* check version number and strike count */ |
| if ( version != 0x00020000L || |
| num_strikes >= 0x10000L ) |
| { |
| FT_ERROR(( "tt_face_load_sbit_strikes: invalid table version!\n" )); |
| error = SFNT_Err_Invalid_File_Format; |
| |
| goto Exit; |
| } |
| |
| /* allocate the strikes table */ |
| if ( FT_NEW_ARRAY( face->sbit_strikes, num_strikes ) ) |
| goto Exit; |
| |
| face->num_sbit_strikes = num_strikes; |
| |
| /* now read each strike table separately */ |
| { |
| TT_SBit_Strike strike = face->sbit_strikes; |
| FT_ULong count = num_strikes; |
| |
| |
| if ( FT_FRAME_ENTER( 48L * num_strikes ) ) |
| goto Exit; |
| |
| while ( count > 0 ) |
| { |
| if ( FT_STREAM_READ_FIELDS( strike_start_fields, strike ) || |
| FT_STREAM_READ_FIELDS( sbit_line_metrics_fields, &strike->hori ) || |
| FT_STREAM_READ_FIELDS( sbit_line_metrics_fields, &strike->vert ) || |
| FT_STREAM_READ_FIELDS( strike_end_fields, strike ) ) |
| break; |
| |
| count--; |
| strike++; |
| } |
| |
| FT_FRAME_EXIT(); |
| } |
| |
| /* allocate the index ranges for each strike table */ |
| { |
| TT_SBit_Strike strike = face->sbit_strikes; |
| FT_ULong count = num_strikes; |
| |
| |
| while ( count > 0 ) |
| { |
| TT_SBit_Range range; |
| FT_ULong count2 = strike->num_ranges; |
| |
| |
| if ( FT_NEW_ARRAY( strike->sbit_ranges, strike->num_ranges ) ) |
| goto Exit; |
| |
| /* read each range */ |
| if ( FT_STREAM_SEEK( table_base + strike->ranges_offset ) || |
| FT_FRAME_ENTER( strike->num_ranges * 8L ) ) |
| goto Exit; |
| |
| range = strike->sbit_ranges; |
| while ( count2 > 0 ) |
| { |
| range->first_glyph = FT_GET_USHORT(); |
| range->last_glyph = FT_GET_USHORT(); |
| range->table_offset = table_base + strike->ranges_offset + |
| FT_GET_ULONG(); |
| count2--; |
| range++; |
| } |
| |
| FT_FRAME_EXIT(); |
| |
| /* Now, read each index table */ |
| count2 = strike->num_ranges; |
| range = strike->sbit_ranges; |
| while ( count2 > 0 ) |
| { |
| /* Read the header */ |
| if ( FT_STREAM_SEEK( range->table_offset ) || |
| FT_FRAME_ENTER( 8L ) ) |
| goto Exit; |
| |
| range->index_format = FT_GET_USHORT(); |
| range->image_format = FT_GET_USHORT(); |
| range->image_offset = FT_GET_ULONG(); |
| |
| FT_FRAME_EXIT(); |
| |
| error = Load_SBit_Range( range, stream ); |
| if ( error ) |
| goto Exit; |
| |
| count2--; |
| range++; |
| } |
| |
| count--; |
| strike++; |
| } |
| } |
| |
| Exit: |
| return error; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* tt_face_free_sbit_strikes */ |
| /* */ |
| /* <Description> */ |
| /* Releases the embedded bitmap tables. */ |
| /* */ |
| /* <Input> */ |
| /* face :: The target face object. */ |
| /* */ |
| FT_LOCAL_DEF( void ) |
| tt_face_free_sbit_strikes( TT_Face face ) |
| { |
| FT_Memory memory = face->root.memory; |
| TT_SBit_Strike strike = face->sbit_strikes; |
| TT_SBit_Strike strike_limit = strike + face->num_sbit_strikes; |
| |
| |
| if ( strike ) |
| { |
| for ( ; strike < strike_limit; strike++ ) |
| { |
| TT_SBit_Range range = strike->sbit_ranges; |
| TT_SBit_Range range_limit = range + strike->num_ranges; |
| |
| |
| if ( range ) |
| { |
| for ( ; range < range_limit; range++ ) |
| { |
| /* release the glyph offsets and codes tables */ |
| /* where appropriate */ |
| FT_FREE( range->glyph_offsets ); |
| FT_FREE( range->glyph_codes ); |
| } |
| } |
| FT_FREE( strike->sbit_ranges ); |
| strike->num_ranges = 0; |
| } |
| FT_FREE( face->sbit_strikes ); |
| } |
| face->num_sbit_strikes = 0; |
| } |
| |
| |
| FT_LOCAL_DEF( FT_Error ) |
| tt_face_set_sbit_strike( TT_Face face, |
| FT_Int x_ppem, |
| FT_Int y_ppem, |
| FT_ULong *astrike_index ) |
| { |
| FT_ULong i; |
| |
| |
| if ( x_ppem < 0 || x_ppem > 255 || |
| y_ppem < 1 || y_ppem > 255 ) |
| return SFNT_Err_Invalid_PPem; |
| |
| for ( i = 0; i < face->num_sbit_strikes; i++ ) |
| { |
| if ( ( face->sbit_strikes[i].y_ppem == y_ppem ) && |
| ( ( x_ppem == 0 ) || |
| ( face->sbit_strikes[i].x_ppem == x_ppem ) ) ) |
| { |
| *astrike_index = i; |
| return SFNT_Err_Ok; |
| } |
| } |
| |
| return SFNT_Err_Invalid_PPem; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* find_sbit_range */ |
| /* */ |
| /* <Description> */ |
| /* Scans a given strike's ranges and return, for a given glyph */ |
| /* index, the corresponding sbit range, and `EBDT' offset. */ |
| /* */ |
| /* <Input> */ |
| /* glyph_index :: The glyph index. */ |
| /* */ |
| /* strike :: The source/current sbit strike. */ |
| /* */ |
| /* <Output> */ |
| /* arange :: The sbit range containing the glyph index. */ |
| /* */ |
| /* aglyph_offset :: The offset of the glyph data in `EBDT' table. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means the glyph index was found. */ |
| /* */ |
| static FT_Error |
| find_sbit_range( FT_UInt glyph_index, |
| TT_SBit_Strike strike, |
| TT_SBit_Range *arange, |
| FT_ULong *aglyph_offset ) |
| { |
| TT_SBit_RangeRec *range, *range_limit; |
| |
| |
| /* check whether the glyph index is within this strike's */ |
| /* glyph range */ |
| if ( glyph_index < (FT_UInt)strike->start_glyph || |
| glyph_index > (FT_UInt)strike->end_glyph ) |
| goto Fail; |
| |
| /* scan all ranges in strike */ |
| range = strike->sbit_ranges; |
| range_limit = range + strike->num_ranges; |
| if ( !range ) |
| goto Fail; |
| |
| for ( ; range < range_limit; range++ ) |
| { |
| if ( glyph_index >= (FT_UInt)range->first_glyph && |
| glyph_index <= (FT_UInt)range->last_glyph ) |
| { |
| FT_UShort delta = (FT_UShort)( glyph_index - range->first_glyph ); |
| |
| |
| switch ( range->index_format ) |
| { |
| case 1: |
| case 3: |
| *aglyph_offset = range->glyph_offsets[delta]; |
| break; |
| |
| case 2: |
| *aglyph_offset = range->image_offset + |
| range->image_size * delta; |
| break; |
| |
| case 4: |
| case 5: |
| { |
| FT_ULong n; |
| |
| |
| for ( n = 0; n < range->num_glyphs; n++ ) |
| { |
| if ( (FT_UInt)range->glyph_codes[n] == glyph_index ) |
| { |
| if ( range->index_format == 4 ) |
| *aglyph_offset = range->glyph_offsets[n]; |
| else |
| *aglyph_offset = range->image_offset + |
| n * range->image_size; |
| goto Found; |
| } |
| } |
| } |
| |
| /* fall-through */ |
| default: |
| goto Fail; |
| } |
| |
| Found: |
| /* return successfully! */ |
| *arange = range; |
| return 0; |
| } |
| } |
| |
| Fail: |
| *arange = 0; |
| *aglyph_offset = 0; |
| |
| return SFNT_Err_Invalid_Argument; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* find_sbit_image */ |
| /* */ |
| /* <Description> */ |
| /* Checks whether an embedded bitmap (an `sbit') exists for a given */ |
| /* glyph, at a given strike. */ |
| /* */ |
| /* <Input> */ |
| /* face :: The target face object. */ |
| /* */ |
| /* glyph_index :: The glyph index. */ |
| /* */ |
| /* strike_index :: The current strike index. */ |
| /* */ |
| /* <Output> */ |
| /* arange :: The SBit range containing the glyph index. */ |
| /* */ |
| /* astrike :: The SBit strike containing the glyph index. */ |
| /* */ |
| /* aglyph_offset :: The offset of the glyph data in `EBDT' table. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. Returns */ |
| /* SFNT_Err_Invalid_Argument if no sbit exists for the requested */ |
| /* glyph. */ |
| /* */ |
| static FT_Error |
| find_sbit_image( TT_Face face, |
| FT_UInt glyph_index, |
| FT_ULong strike_index, |
| TT_SBit_Range *arange, |
| TT_SBit_Strike *astrike, |
| FT_ULong *aglyph_offset ) |
| { |
| FT_Error error; |
| TT_SBit_Strike strike; |
| |
| |
| if ( !face->sbit_strikes || |
| ( face->num_sbit_strikes <= strike_index ) ) |
| goto Fail; |
| |
| strike = &face->sbit_strikes[strike_index]; |
| |
| error = find_sbit_range( glyph_index, strike, |
| arange, aglyph_offset ); |
| if ( error ) |
| goto Fail; |
| |
| *astrike = strike; |
| |
| return SFNT_Err_Ok; |
| |
| Fail: |
| /* no embedded bitmap for this glyph in face */ |
| *arange = 0; |
| *astrike = 0; |
| *aglyph_offset = 0; |
| |
| return SFNT_Err_Invalid_Argument; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* load_sbit_metrics */ |
| /* */ |
| /* <Description> */ |
| /* Gets the big metrics for a given SBit. */ |
| /* */ |
| /* <Input> */ |
| /* stream :: The input stream. */ |
| /* */ |
| /* range :: The SBit range containing the glyph. */ |
| /* */ |
| /* <Output> */ |
| /* big_metrics :: A big SBit metrics structure for the glyph. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. */ |
| /* */ |
| /* <Note> */ |
| /* The stream cursor must be positioned at the glyph's offset within */ |
| /* the `EBDT' table before the call. */ |
| /* */ |
| /* If the image format uses variable metrics, the stream cursor is */ |
| /* positioned just after the metrics header in the `EBDT' table on */ |
| /* function exit. */ |
| /* */ |
| static FT_Error |
| load_sbit_metrics( FT_Stream stream, |
| TT_SBit_Range range, |
| TT_SBit_Metrics metrics ) |
| { |
| FT_Error error = SFNT_Err_Ok; |
| |
| |
| switch ( range->image_format ) |
| { |
| case 1: |
| case 2: |
| case 8: |
| /* variable small metrics */ |
| { |
| TT_SBit_SmallMetricsRec smetrics; |
| |
| const FT_Frame_Field sbit_small_metrics_fields[] = |
| { |
| #undef FT_STRUCTURE |
| #define FT_STRUCTURE TT_SBit_SmallMetricsRec |
| |
| FT_FRAME_START( 5 ), |
| FT_FRAME_BYTE( height ), |
| FT_FRAME_BYTE( width ), |
| FT_FRAME_CHAR( bearingX ), |
| FT_FRAME_CHAR( bearingY ), |
| FT_FRAME_BYTE( advance ), |
| FT_FRAME_END |
| }; |
| |
| |
| /* read small metrics */ |
| if ( FT_STREAM_READ_FIELDS( sbit_small_metrics_fields, &smetrics ) ) |
| goto Exit; |
| |
| /* convert it to a big metrics */ |
| metrics->height = smetrics.height; |
| metrics->width = smetrics.width; |
| metrics->horiBearingX = smetrics.bearingX; |
| metrics->horiBearingY = smetrics.bearingY; |
| metrics->horiAdvance = smetrics.advance; |
| |
| /* these metrics are made up at a higher level when */ |
| /* needed. */ |
| metrics->vertBearingX = 0; |
| metrics->vertBearingY = 0; |
| metrics->vertAdvance = 0; |
| } |
| break; |
| |
| case 6: |
| case 7: |
| case 9: |
| /* variable big metrics */ |
| if ( FT_STREAM_READ_FIELDS( sbit_metrics_fields, metrics ) ) |
| goto Exit; |
| break; |
| |
| case 5: |
| default: /* constant metrics */ |
| if ( range->index_format == 2 || range->index_format == 5 ) |
| *metrics = range->metrics; |
| else |
| return SFNT_Err_Invalid_File_Format; |
| } |
| |
| Exit: |
| return error; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* crop_bitmap */ |
| /* */ |
| /* <Description> */ |
| /* Crops a bitmap to its tightest bounding box, and adjusts its */ |
| /* metrics. */ |
| /* */ |
| /* <InOut> */ |
| /* map :: The bitmap. */ |
| /* */ |
| /* metrics :: The corresponding metrics structure. */ |
| /* */ |
| static void |
| crop_bitmap( FT_Bitmap* map, |
| TT_SBit_Metrics metrics ) |
| { |
| /***********************************************************************/ |
| /* */ |
| /* In this situation, some bounding boxes of embedded bitmaps are too */ |
| /* large. We need to crop it to a reasonable size. */ |
| /* */ |
| /* --------- */ |
| /* | | ----- */ |
| /* | *** | |***| */ |
| /* | * | | * | */ |
| /* | * | ------> | * | */ |
| /* | * | | * | */ |
| /* | * | | * | */ |
| /* | *** | |***| */ |
| /* --------- ----- */ |
| /* */ |
| /***********************************************************************/ |
| |
| FT_Int rows, count; |
| FT_Long line_len; |
| FT_Byte* line; |
| |
| |
| /***********************************************************************/ |
| /* */ |
| /* first of all, check the top-most lines of the bitmap, and remove */ |
| /* them if they're empty. */ |
| /* */ |
| { |
| line = (FT_Byte*)map->buffer; |
| rows = map->rows; |
| line_len = map->pitch; |
| |
| |
| for ( count = 0; count < rows; count++ ) |
| { |
| FT_Byte* cur = line; |
| FT_Byte* limit = line + line_len; |
| |
| |
| for ( ; cur < limit; cur++ ) |
| if ( cur[0] ) |
| goto Found_Top; |
| |
| /* the current line was empty - skip to next one */ |
| line = limit; |
| } |
| |
| Found_Top: |
| /* check that we have at least one filled line */ |
| if ( count >= rows ) |
| goto Empty_Bitmap; |
| |
| /* now, crop the empty upper lines */ |
| if ( count > 0 ) |
| { |
| line = (FT_Byte*)map->buffer; |
| |
| FT_MEM_MOVE( line, line + count * line_len, |
| ( rows - count ) * line_len ); |
| |
| metrics->height = (FT_Byte)( metrics->height - count ); |
| metrics->horiBearingY = (FT_Char)( metrics->horiBearingY - count ); |
| metrics->vertBearingY = (FT_Char)( metrics->vertBearingY - count ); |
| |
| map->rows -= count; |
| rows -= count; |
| } |
| } |
| |
| /***********************************************************************/ |
| /* */ |
| /* second, crop the lower lines */ |
| /* */ |
| { |
| line = (FT_Byte*)map->buffer + ( rows - 1 ) * line_len; |
| |
| for ( count = 0; count < rows; count++ ) |
| { |
| FT_Byte* cur = line; |
| FT_Byte* limit = line + line_len; |
| |
| |
| for ( ; cur < limit; cur++ ) |
| if ( cur[0] ) |
| goto Found_Bottom; |
| |
| /* the current line was empty - skip to previous one */ |
| line -= line_len; |
| } |
| |
| Found_Bottom: |
| if ( count > 0 ) |
| { |
| metrics->height = (FT_Byte)( metrics->height - count ); |
| rows -= count; |
| map->rows -= count; |
| } |
| } |
| |
| /***********************************************************************/ |
| /* */ |
| /* third, get rid of the space on the left side of the glyph */ |
| /* */ |
| do |
| { |
| FT_Byte* limit; |
| |
| |
| line = (FT_Byte*)map->buffer; |
| limit = line + rows * line_len; |
| |
| for ( ; line < limit; line += line_len ) |
| if ( line[0] & 0x80 ) |
| goto Found_Left; |
| |
| /* shift the whole glyph one pixel to the left */ |
| line = (FT_Byte*)map->buffer; |
| limit = line + rows * line_len; |
| |
| for ( ; line < limit; line += line_len ) |
| { |
| FT_Int n, width = map->width; |
| FT_Byte old; |
| FT_Byte* cur = line; |
| |
| |
| old = (FT_Byte)(cur[0] << 1); |
| for ( n = 8; n < width; n += 8 ) |
| { |
| FT_Byte val; |
| |
| |
| val = cur[1]; |
| cur[0] = (FT_Byte)( old | ( val >> 7 ) ); |
| old = (FT_Byte)( val << 1 ); |
| cur++; |
| } |
| cur[0] = old; |
| } |
| |
| map->width--; |
| metrics->horiBearingX++; |
| metrics->vertBearingX++; |
| metrics->width--; |
| |
| } while ( map->width > 0 ); |
| |
| Found_Left: |
| |
| /***********************************************************************/ |
| /* */ |
| /* finally, crop the bitmap width to get rid of the space on the right */ |
| /* side of the glyph. */ |
| /* */ |
| do |
| { |
| FT_Int right = map->width - 1; |
| FT_Byte* limit; |
| FT_Byte mask; |
| |
| |
| line = (FT_Byte*)map->buffer + ( right >> 3 ); |
| limit = line + rows * line_len; |
| mask = (FT_Byte)( 0x80 >> ( right & 7 ) ); |
| |
| for ( ; line < limit; line += line_len ) |
| if ( line[0] & mask ) |
| goto Found_Right; |
| |
| /* crop the whole glyph to the right */ |
| map->width--; |
| metrics->width--; |
| |
| } while ( map->width > 0 ); |
| |
| Found_Right: |
| /* all right, the bitmap was cropped */ |
| return; |
| |
| Empty_Bitmap: |
| map->width = 0; |
| map->rows = 0; |
| map->pitch = 0; |
| map->pixel_mode = FT_PIXEL_MODE_MONO; |
| } |
| |
| |
| static FT_Error |
| Load_SBit_Single( FT_Bitmap* map, |
| FT_Int x_offset, |
| FT_Int y_offset, |
| FT_Int pix_bits, |
| FT_UShort image_format, |
| TT_SBit_Metrics metrics, |
| FT_Stream stream ) |
| { |
| FT_Error error; |
| |
| |
| /* check that the source bitmap fits into the target pixmap */ |
| if ( x_offset < 0 || x_offset + metrics->width > map->width || |
| y_offset < 0 || y_offset + metrics->height > map->rows ) |
| { |
| error = SFNT_Err_Invalid_Argument; |
| |
| goto Exit; |
| } |
| |
| { |
| FT_Int glyph_width = metrics->width; |
| FT_Int glyph_height = metrics->height; |
| FT_Int glyph_size; |
| FT_Int line_bits = pix_bits * glyph_width; |
| FT_Bool pad_bytes = 0; |
| |
| |
| /* compute size of glyph image */ |
| switch ( image_format ) |
| { |
| case 1: /* byte-padded formats */ |
| case 6: |
| { |
| FT_Int line_length; |
| |
| |
| switch ( pix_bits ) |
| { |
| case 1: |
| line_length = ( glyph_width + 7 ) >> 3; |
| break; |
| case 2: |
| line_length = ( glyph_width + 3 ) >> 2; |
| break; |
| case 4: |
| line_length = ( glyph_width + 1 ) >> 1; |
| break; |
| default: |
| line_length = glyph_width; |
| } |
| |
| glyph_size = glyph_height * line_length; |
| pad_bytes = 1; |
| } |
| break; |
| |
| case 2: |
| case 5: |
| case 7: |
| line_bits = glyph_width * pix_bits; |
| glyph_size = ( glyph_height * line_bits + 7 ) >> 3; |
| break; |
| |
| default: /* invalid format */ |
| return SFNT_Err_Invalid_File_Format; |
| } |
| |
| /* Now read data and draw glyph into target pixmap */ |
| if ( FT_FRAME_ENTER( glyph_size ) ) |
| goto Exit; |
| |
| /* don't forget to multiply `x_offset' by `map->pix_bits' as */ |
| /* the sbit blitter doesn't make a difference between pixmap */ |
| /* depths. */ |
| blit_sbit( map, (FT_Byte*)stream->cursor, line_bits, pad_bytes, |
| x_offset * pix_bits, y_offset ); |
| |
| FT_FRAME_EXIT(); |
| } |
| |
| Exit: |
| return error; |
| } |
| |
| |
| static FT_Error |
| Load_SBit_Image( TT_SBit_Strike strike, |
| TT_SBit_Range range, |
| FT_ULong ebdt_pos, |
| FT_ULong glyph_offset, |
| FT_Bitmap* map, |
| FT_Int x_offset, |
| FT_Int y_offset, |
| FT_Stream stream, |
| TT_SBit_Metrics metrics ) |
| { |
| FT_Memory memory = stream->memory; |
| FT_Error error; |
| |
| |
| /* place stream at beginning of glyph data and read metrics */ |
| if ( FT_STREAM_SEEK( ebdt_pos + glyph_offset ) ) |
| goto Exit; |
| |
| error = load_sbit_metrics( stream, range, metrics ); |
| if ( error ) |
| goto Exit; |
| |
| /* this function is recursive. At the top-level call, the */ |
| /* field map.buffer is NULL. We thus begin by finding the */ |
| /* dimensions of the higher-level glyph to allocate the */ |
| /* final pixmap buffer */ |
| if ( map->buffer == 0 ) |
| { |
| FT_Long size; |
| |
| |
| map->width = metrics->width; |
| map->rows = metrics->height; |
| |
| switch ( strike->bit_depth ) |
| { |
| case 1: |
| map->pixel_mode = FT_PIXEL_MODE_MONO; |
| map->pitch = ( map->width + 7 ) >> 3; |
| break; |
| |
| case 2: |
| map->pixel_mode = FT_PIXEL_MODE_GRAY2; |
| map->pitch = ( map->width + 3 ) >> 2; |
| break; |
| |
| case 4: |
| map->pixel_mode = FT_PIXEL_MODE_GRAY4; |
| map->pitch = ( map->width + 1 ) >> 1; |
| break; |
| |
| case 8: |
| map->pixel_mode = FT_PIXEL_MODE_GRAY; |
| map->pitch = map->width; |
| break; |
| |
| default: |
| return SFNT_Err_Invalid_File_Format; |
| } |
| |
| size = map->rows * map->pitch; |
| |
| /* check that there is no empty image */ |
| if ( size == 0 ) |
| goto Exit; /* exit successfully! */ |
| |
| if ( FT_ALLOC( map->buffer, size ) ) |
| goto Exit; |
| } |
| |
| switch ( range->image_format ) |
| { |
| case 1: /* single sbit image - load it */ |
| case 2: |
| case 5: |
| case 6: |
| case 7: |
| return Load_SBit_Single( map, x_offset, y_offset, strike->bit_depth, |
| range->image_format, metrics, stream ); |
| |
| case 8: /* compound format */ |
| FT_Stream_Skip( stream, 1L ); |
| /* fallthrough */ |
| |
| case 9: |
| break; |
| |
| default: /* invalid image format */ |
| return SFNT_Err_Invalid_File_Format; |
| } |
| |
| /* All right, we have a compound format. First of all, read */ |
| /* the array of elements. */ |
| { |
| TT_SBit_Component components; |
| TT_SBit_Component comp; |
| FT_UShort num_components, count; |
| |
| |
| if ( FT_READ_USHORT( num_components ) || |
| FT_NEW_ARRAY( components, num_components ) ) |
| goto Exit; |
| |
| count = num_components; |
| |
| if ( FT_FRAME_ENTER( 4L * num_components ) ) |
| goto Fail_Memory; |
| |
| for ( comp = components; count > 0; count--, comp++ ) |
| { |
| comp->glyph_code = FT_GET_USHORT(); |
| comp->x_offset = FT_GET_CHAR(); |
| comp->y_offset = FT_GET_CHAR(); |
| } |
| |
| FT_FRAME_EXIT(); |
| |
| /* Now recursively load each element glyph */ |
| count = num_components; |
| comp = components; |
| for ( ; count > 0; count--, comp++ ) |
| { |
| TT_SBit_Range elem_range; |
| TT_SBit_MetricsRec elem_metrics; |
| FT_ULong elem_offset; |
| |
| |
| /* find the range for this element */ |
| error = find_sbit_range( comp->glyph_code, |
| strike, |
| &elem_range, |
| &elem_offset ); |
| if ( error ) |
| goto Fail_Memory; |
| |
| /* now load the element, recursively */ |
| error = Load_SBit_Image( strike, |
| elem_range, |
| ebdt_pos, |
| elem_offset, |
| map, |
| x_offset + comp->x_offset, |
| y_offset + comp->y_offset, |
| stream, |
| &elem_metrics ); |
| if ( error ) |
| goto Fail_Memory; |
| } |
| |
| Fail_Memory: |
| FT_FREE( components ); |
| } |
| |
| Exit: |
| return error; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* tt_face_load_sbit_image */ |
| /* */ |
| /* <Description> */ |
| /* Loads a given glyph sbit image from the font resource. This also */ |
| /* returns its metrics. */ |
| /* */ |
| /* <Input> */ |
| /* face :: The target face object. */ |
| /* */ |
| /* strike_index :: The current strike index. */ |
| /* */ |
| /* glyph_index :: The current glyph index. */ |
| /* */ |
| /* load_flags :: The glyph load flags (the code checks for the flag */ |
| /* FT_LOAD_CROP_BITMAP). */ |
| /* */ |
| /* stream :: The input stream. */ |
| /* */ |
| /* <Output> */ |
| /* map :: The target pixmap. */ |
| /* */ |
| /* metrics :: A big sbit metrics structure for the glyph image. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. Returns an error if no */ |
| /* glyph sbit exists for the index. */ |
| /* */ |
| /* <Note> */ |
| /* The `map.buffer' field is always freed before the glyph is loaded. */ |
| /* */ |
| FT_LOCAL_DEF( FT_Error ) |
| tt_face_load_sbit_image( TT_Face face, |
| FT_ULong strike_index, |
| FT_UInt glyph_index, |
| FT_UInt load_flags, |
| FT_Stream stream, |
| FT_Bitmap *map, |
| TT_SBit_MetricsRec *metrics ) |
| { |
| FT_Error error; |
| FT_Memory memory = stream->memory; |
| FT_ULong ebdt_pos, glyph_offset; |
| |
| TT_SBit_Strike strike; |
| TT_SBit_Range range; |
| |
| |
| /* Check whether there is a glyph sbit for the current index */ |
| error = find_sbit_image( face, glyph_index, strike_index, |
| &range, &strike, &glyph_offset ); |
| if ( error ) |
| goto Exit; |
| |
| /* now, find the location of the `EBDT' table in */ |
| /* the font file */ |
| error = face->goto_table( face, TTAG_EBDT, stream, 0 ); |
| if ( error ) |
| error = face->goto_table( face, TTAG_bdat, stream, 0 ); |
| if (error) |
| goto Exit; |
| |
| ebdt_pos = FT_STREAM_POS(); |
| |
| /* clear the bitmap & load the bitmap */ |
| if ( face->root.glyph->flags & FT_GLYPH_OWN_BITMAP ) |
| FT_FREE( map->buffer ); |
| |
| map->rows = map->pitch = map->width = 0; |
| |
| error = Load_SBit_Image( strike, range, ebdt_pos, glyph_offset, |
| map, 0, 0, stream, metrics ); |
| if ( error ) |
| goto Exit; |
| |
| /* the glyph slot owns this bitmap buffer */ |
| face->root.glyph->flags |= FT_GLYPH_OWN_BITMAP; |
| |
| /* setup vertical metrics if needed */ |
| if ( strike->flags & 1 ) |
| { |
| /* in case of a horizontal strike only */ |
| FT_Int advance; |
| |
| |
| advance = strike->hori.ascender - strike->hori.descender; |
| |
| /* some heuristic values */ |
| |
| metrics->vertBearingX = (FT_Char)(-metrics->width / 2 ); |
| metrics->vertBearingY = (FT_Char)( advance / 10 ); |
| metrics->vertAdvance = (FT_Char)( advance * 12 / 10 ); |
| } |
| |
| /* Crop the bitmap now, unless specified otherwise */ |
| if ( load_flags & FT_LOAD_CROP_BITMAP ) |
| crop_bitmap( map, metrics ); |
| |
| Exit: |
| return error; |
| } |
| |
| |
| /* END */ |
