| /***************************************************************************/ |
| /* */ |
| /* ttsbit.c */ |
| /* */ |
| /* TrueType and OpenType embedded bitmap support (body). */ |
| /* */ |
| /* Copyright 1996-1999 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. */ |
| /* */ |
| /* */ |
| /* WARNING: This file should not be compiled directly, it is meant to be */ |
| /* included in the source of several font drivers (i.e., the TTF */ |
| /* and OTF drivers). */ |
| /* */ |
| /***************************************************************************/ |
| |
| |
| #include <freetype/internal/ftdebug.h> |
| #include <freetype/internal/tterrors.h> |
| #include <freetype/tttags.h> |
| |
| #include <ttsbit.h> |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <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, |
| char* 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_Byte 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 = x_offset & 7; /* current write shift */ |
| FT_Byte space = 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)*source++) << (8 - loaded); |
| loaded += 8; |
| } |
| |
| /* now write one byte */ |
| val = (FT_Byte)(acc >> 8); |
| if (shift) |
| { |
| cur[0] |= val >> shift; |
| cur[1] |= 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 ( loaded < count ) |
| { |
| acc |= ((FT_UShort)*source++) << (8 - loaded); |
| loaded += 8; |
| } |
| |
| /* now write remaining bits */ |
| val = ((FT_Byte)(acc >> 8)) & ~(0xFF >> count); |
| cur[0] |= val >> shift; |
| |
| if ( count > space ) |
| cur[1] |= val << space; |
| |
| acc <<= count; |
| loaded -= count; |
| } |
| |
| /* now, skip to next line */ |
| if ( byte_padded ) |
| acc = loaded = 0; /* clear accumulator on byte-padded lines */ |
| |
| line_buff += line_incr; |
| } |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* TT_Load_Small_SBit_Metrics */ |
| /* */ |
| /* <Description> */ |
| /* Loads a small bitmap metrics record. */ |
| /* */ |
| /* <Input> */ |
| /* stream :: The input stream. */ |
| /* */ |
| /* <Output> */ |
| /* metrics :: A small metrics structure. */ |
| /* */ |
| static |
| void TT_Load_Small_SBit_Metrics( TT_SBit_Small_Metrics* metrics, |
| FT_Stream stream ) |
| { |
| metrics->height = GET_Byte(); |
| metrics->width = GET_Byte(); |
| metrics->bearingX = GET_Char(); |
| metrics->bearingY = GET_Char(); |
| metrics->advance = GET_Byte(); |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* TT_Load_SBit_Metrics */ |
| /* */ |
| /* <Description> */ |
| /* Loads a bitmap metrics record. */ |
| /* */ |
| /* <Input> */ |
| /* stream :: The input stream. */ |
| /* */ |
| /* <Output> */ |
| /* metrics :: A metrics structure. */ |
| /* */ |
| static |
| void TT_Load_SBit_Metrics( TT_SBit_Metrics* metrics, |
| FT_Stream stream ) |
| { |
| metrics->height = GET_Byte(); |
| metrics->width = GET_Byte(); |
| |
| metrics->horiBearingX = GET_Char(); |
| metrics->horiBearingY = GET_Char(); |
| metrics->horiAdvance = GET_Byte(); |
| |
| metrics->vertBearingX = GET_Char(); |
| metrics->vertBearingY = GET_Char(); |
| metrics->vertAdvance = GET_Byte(); |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* TT_Load_SBit_Line_Metrics */ |
| /* */ |
| /* <Description> */ |
| /* Loads a bitmap line metrics record. */ |
| /* */ |
| /* <Input> */ |
| /* stream :: The input stream. */ |
| /* */ |
| /* <Output> */ |
| /* metrics :: A line metrics structure. */ |
| /* */ |
| static |
| void TT_Load_SBit_Line_Metrics( TT_SBit_Line_Metrics* metrics, |
| FT_Stream stream ) |
| { |
| metrics->ascender = GET_Char(); |
| metrics->descender = GET_Char(); |
| metrics->max_width = GET_Byte(); |
| |
| metrics->caret_slope_numerator = GET_Char(); |
| metrics->caret_slope_denominator = GET_Char(); |
| metrics->caret_offset = GET_Char(); |
| |
| metrics->min_origin_SB = GET_Char(); |
| metrics->min_advance_SB = GET_Char(); |
| metrics->max_before_BL = GET_Char(); |
| metrics->min_after_BL = GET_Char(); |
| metrics->pads[0] = GET_Char(); |
| metrics->pads[1] = GET_Char(); |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <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> */ |
| /* TrueType error code. 0 means success. */ |
| /* */ |
| static |
| TT_Error Load_SBit_Const_Metrics( TT_SBit_Range* range, |
| FT_Stream stream ) |
| { |
| TT_Error error; |
| |
| if ( !ACCESS_Frame( 12L ) ) |
| { |
| range->image_size = GET_ULong(); |
| TT_Load_SBit_Metrics( &range->metrics, stream ); |
| |
| FORGET_Frame(); |
| } |
| |
| return error; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <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> */ |
| /* TrueType error code. 0 means success. */ |
| /* */ |
| static |
| TT_Error Load_SBit_Range_Codes( TT_SBit_Range* range, |
| FT_Stream stream, |
| TT_Bool load_offsets ) |
| { |
| TT_Error error; |
| TT_ULong count, n, size; |
| FT_Memory memory = stream->memory; |
| |
| |
| if ( READ_ULong( count ) ) |
| goto Exit; |
| |
| range->num_glyphs = count; |
| |
| /* Allocate glyph offsets table if needed */ |
| if ( load_offsets ) |
| { |
| if ( ALLOC_ARRAY( range->glyph_offsets, count, TT_ULong ) ) |
| goto Exit; |
| |
| size = count * 4L; |
| } |
| else |
| size = count * 2L; |
| |
| /* Allocate glyph codes table and access frame */ |
| if ( ALLOC_ARRAY ( range->glyph_codes, count, TT_UShort ) || |
| ACCESS_Frame( size ) ) |
| goto Exit; |
| |
| for ( n = 0; n < count; n++ ) |
| { |
| range->glyph_codes[n] = GET_UShort(); |
| |
| if (load_offsets) |
| range->glyph_offsets[n] = (TT_ULong)range->image_offset + |
| GET_UShort(); |
| } |
| |
| FORGET_Frame(); |
| |
| 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> */ |
| /* TrueType error code. 0 means success. */ |
| /* */ |
| static |
| TT_Error Load_SBit_Range( TT_SBit_Range* range, |
| FT_Stream stream ) |
| { |
| TT_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 */ |
| { |
| TT_ULong num_glyphs, n; |
| TT_Int size_elem; |
| TT_Bool large = (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 ( ALLOC_ARRAY( range->glyph_offsets, |
| num_glyphs, TT_ULong ) || |
| |
| ACCESS_Frame( num_glyphs * size_elem ) ) |
| goto Exit; |
| |
| for ( n = 0; n < num_glyphs; n++ ) |
| range->glyph_offsets[n] = (TT_ULong)( range->image_offset + |
| (large ? GET_ULong() : GET_UShort()) ); |
| FORGET_Frame(); |
| } |
| 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 = TT_Err_Invalid_File_Format; |
| } |
| |
| Exit: |
| return error; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* TT_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> */ |
| /* TrueType error code. 0 means success. */ |
| /* */ |
| LOCAL_FUNC |
| TT_Error TT_Load_SBit_Strikes( TT_Face face, |
| FT_Stream stream ) |
| { |
| TT_Error error = 0; |
| FT_Memory memory = stream->memory; |
| TT_Fixed version; |
| TT_ULong num_strikes; |
| TT_ULong table_base; |
| |
| |
| /* this table is optional */ |
| error = face->goto_table( face, TTAG_EBLC, stream, 0 ); |
| if (error) |
| { |
| error = 0; |
| goto Exit; |
| } |
| |
| table_base = FILE_Pos(); |
| if ( ACCESS_Frame( 8L ) ) |
| goto Exit; |
| |
| version = GET_Long(); |
| num_strikes = GET_ULong(); |
| |
| FORGET_Frame(); |
| |
| /* check version number and strike count */ |
| if ( version != 0x00020000 || |
| num_strikes >= 0x10000 ) |
| { |
| FT_ERROR(( "TT_Load_SBit_Strikes: invalid table version!\n" )); |
| error = TT_Err_Invalid_File_Format; |
| |
| goto Exit; |
| } |
| |
| /* allocate the strikes table */ |
| if ( ALLOC_ARRAY( face->sbit_strikes, num_strikes, TT_SBit_Strike ) ) |
| goto Exit; |
| |
| face->num_sbit_strikes = num_strikes; |
| |
| /* now read each strike table separately */ |
| { |
| TT_SBit_Strike* strike = face->sbit_strikes; |
| TT_ULong count = num_strikes; |
| |
| if ( ACCESS_Frame( 48L * num_strikes ) ) |
| goto Exit; |
| |
| while ( count > 0 ) |
| { |
| TT_ULong indexTablesSize; |
| |
| |
| strike->ranges_offset = GET_ULong(); |
| indexTablesSize = GET_ULong(); /* don't save */ |
| |
| strike->num_ranges = GET_ULong(); |
| strike->color_ref = GET_ULong(); |
| |
| TT_Load_SBit_Line_Metrics( &strike->hori, stream ); |
| TT_Load_SBit_Line_Metrics( &strike->vert, stream ); |
| |
| strike->start_glyph = GET_UShort(); |
| strike->end_glyph = GET_UShort(); |
| strike->x_ppem = GET_Byte(); |
| strike->y_ppem = GET_Byte(); |
| strike->bit_depth = GET_Byte(); |
| strike->flags = GET_Char(); |
| |
| count--; |
| strike++; |
| } |
| |
| FORGET_Frame(); |
| } |
| |
| /* allocate the index ranges for each strike table */ |
| { |
| TT_SBit_Strike* strike = face->sbit_strikes; |
| TT_ULong count = num_strikes; |
| |
| |
| while ( count > 0 ) |
| { |
| TT_SBit_Range* range; |
| TT_ULong count2 = strike->num_ranges; |
| |
| |
| if ( ALLOC_ARRAY( strike->sbit_ranges, |
| strike->num_ranges, |
| TT_SBit_Range ) ) |
| goto Exit; |
| |
| /* read each range */ |
| if ( FILE_Seek( table_base + strike->ranges_offset ) || |
| ACCESS_Frame( strike->num_ranges * 8L ) ) |
| goto Exit; |
| |
| range = strike->sbit_ranges; |
| while ( count2 > 0 ) |
| { |
| range->first_glyph = GET_UShort(); |
| range->last_glyph = GET_UShort(); |
| range->table_offset = table_base + strike->ranges_offset |
| + GET_ULong(); |
| count2--; |
| range++; |
| } |
| |
| FORGET_Frame(); |
| |
| /* Now, read each index table */ |
| count2 = strike->num_ranges; |
| range = strike->sbit_ranges; |
| while ( count2 > 0 ) |
| { |
| /* Read the header */ |
| if ( FILE_Seek( range->table_offset ) || |
| ACCESS_Frame( 8L ) ) |
| goto Exit; |
| |
| range->index_format = GET_UShort(); |
| range->image_format = GET_UShort(); |
| range->image_offset = GET_ULong(); |
| |
| FORGET_Frame(); |
| |
| error = Load_SBit_Range( range, stream ); |
| if ( error ) |
| goto Exit; |
| |
| count2--; |
| range++; |
| } |
| |
| count--; |
| strike++; |
| } |
| } |
| |
| Exit: |
| return error; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* TT_Free_SBit_Strikes */ |
| /* */ |
| /* <Description> */ |
| /* Releases the embedded bitmap tables. */ |
| /* */ |
| /* <Input> */ |
| /* face :: The target face object. */ |
| /* */ |
| LOCAL_FUNC |
| void TT_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 */ |
| FREE( range->glyph_offsets ); |
| FREE( range->glyph_codes ); |
| } |
| } |
| FREE( strike->sbit_ranges ); |
| strike->num_ranges = 0; |
| } |
| FREE( face->sbit_strikes ); |
| } |
| face->num_sbit_strikes = 0; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <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> */ |
| /* TrueType error code. 0 means the glyph index was found. */ |
| /* */ |
| static |
| TT_Error Find_SBit_Range( TT_UInt glyph_index, |
| TT_SBit_Strike* strike, |
| TT_SBit_Range** arange, |
| TT_ULong* aglyph_offset ) |
| { |
| TT_SBit_Range *range, *range_limit; |
| |
| |
| /* check whether the glyph index is within this strike's */ |
| /* glyph range */ |
| if ( glyph_index < strike->start_glyph || |
| glyph_index > 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 >= range->first_glyph && |
| glyph_index <= range->last_glyph ) |
| { |
| TT_UShort delta = 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: |
| { |
| TT_ULong n; |
| |
| |
| for ( n = 0; n < range->num_glyphs; n++ ) |
| { |
| if ( 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; |
| break; |
| } |
| } |
| } |
| |
| /* fall-through */ |
| default: |
| goto Fail; |
| } |
| |
| /* return successfully! */ |
| *arange = range; |
| |
| return 0; |
| } |
| } |
| |
| Fail: |
| *arange = 0; |
| *aglyph_offset = 0; |
| |
| return TT_Err_Invalid_Argument; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Find_SBit_Image */ |
| /* */ |
| /* <Description> */ |
| /* Checks whether an embedded bitmap (an `sbit') exists for a given */ |
| /* glyph, at given x and y ppems. */ |
| /* */ |
| /* <Input> */ |
| /* face :: The target face object. */ |
| /* glyph_index :: The glyph index. */ |
| /* x_ppem :: The horizontal resolution in points per EM. */ |
| /* y_ppem :: The vertical resolution in points per EM. */ |
| /* */ |
| /* <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> */ |
| /* TrueType error code. 0 means success. Returns */ |
| /* TT_Err_Invalid_Argument if no sbit exist for the requested glyph. */ |
| /* */ |
| static |
| TT_Error Find_SBit_Image( TT_Face face, |
| TT_UInt glyph_index, |
| TT_Int x_ppem, |
| TT_Int y_ppem, |
| |
| TT_SBit_Range** arange, |
| TT_SBit_Strike** astrike, |
| TT_ULong* aglyph_offset ) |
| { |
| TT_SBit_Strike* strike = face->sbit_strikes; |
| TT_SBit_Strike* strike_limit = strike + face->num_sbit_strikes; |
| |
| |
| if ( !strike) |
| goto Fail; |
| |
| for ( ; strike < strike_limit; strike++ ) |
| { |
| if ( strike->x_ppem == x_ppem && strike->y_ppem == y_ppem ) |
| { |
| TT_Error error; |
| |
| |
| error = Find_SBit_Range( glyph_index, strike, arange, aglyph_offset ); |
| if ( error ) |
| goto Fail; |
| |
| *astrike = strike; |
| |
| return TT_Err_Ok; |
| } |
| } |
| |
| Fail: |
| /* no embedded bitmap for this glyph in face */ |
| *arange = 0; |
| *astrike = 0; |
| *aglyph_offset = 0; |
| |
| return TT_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> */ |
| /* TrueType 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 |
| TT_Error Load_SBit_Metrics( FT_Stream stream, |
| TT_SBit_Range* range, |
| TT_SBit_Metrics* metrics ) |
| { |
| TT_Error error = TT_Err_Ok; |
| |
| |
| switch ( range->index_format ) |
| { |
| case 1: /* variable metrics */ |
| case 3: |
| case 4: |
| { |
| switch ( range->image_format ) |
| { |
| case 1: /* small metrics */ |
| case 2: |
| case 8: |
| { |
| TT_SBit_Small_Metrics smetrics; |
| |
| |
| /* read small metrics */ |
| if ( ACCESS_Frame( 5L ) ) |
| goto Exit; |
| TT_Load_Small_SBit_Metrics( &smetrics, stream ); |
| FORGET_Frame(); |
| |
| /* 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; |
| |
| default: /* big metrics */ |
| if ( ACCESS_Frame( 8L ) ) |
| goto Exit; |
| TT_Load_SBit_Metrics( metrics, stream ); |
| FORGET_Frame(); |
| } |
| } |
| break; |
| |
| default: /* constant metrics */ |
| *metrics = range->metrics; |
| } |
| |
| Exit: |
| return error; |
| } |
| |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* Crop_Bitmap */ |
| /* */ |
| /* <Description> */ |
| /* Crops a bitmap to its tightest bounding box, and adjusts its */ |
| /* metrics. */ |
| /* */ |
| /* <Input> */ |
| /* image :: The input glyph slot. */ |
| /* */ |
| /* 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. */ |
| /* */ |
| /* --------- */ |
| /* | | ----- */ |
| /* | *** | |***| */ |
| /* | * | | * | */ |
| /* | * | ------> | * | */ |
| /* | * | | * | */ |
| /* | * | | * | */ |
| /* | *** | |***| */ |
| /* --------- ----- */ |
| /* */ |
| /***********************************************************************/ |
| |
| TT_Int rows, count; |
| TT_Long line_len; |
| TT_Byte* line; |
| |
| |
| /***********************************************************************/ |
| /* */ |
| /* first of all, checks the top-most lines of the bitmap, and removes */ |
| /* them if they're empty. */ |
| /* */ |
| { |
| line = (TT_Byte*)map->buffer; |
| rows = map->rows; |
| line_len = map->pitch; |
| |
| |
| for ( count = 0; count < rows; count++ ) |
| { |
| TT_Byte* cur = line; |
| TT_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 = (TT_Byte*)map->buffer; |
| |
| MEM_Move( line, line + count * line_len, (rows - count) * line_len ); |
| |
| metrics->height -= count; |
| metrics->horiBearingY -= count; |
| metrics->vertBearingY -= count; |
| |
| map->rows -= count; |
| rows -= count; |
| } |
| } |
| |
| /***********************************************************************/ |
| /* */ |
| /* second, crop the lower lines */ |
| /* */ |
| { |
| line = (TT_Byte*)map->buffer + (rows - 1) * line_len; |
| |
| for ( count = 0; count < rows; count++ ) |
| { |
| TT_Byte* cur = line; |
| TT_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 -= count; |
| rows -= count; |
| map->rows -= count; |
| } |
| } |
| |
| /***********************************************************************/ |
| /* */ |
| /* third, get rid of the space on the left side of the glyph */ |
| /* */ |
| do |
| { |
| TT_Byte* limit; |
| |
| |
| line = (TT_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 = (TT_Byte*)map->buffer; |
| limit = line + rows * line_len; |
| |
| for ( ; line < limit; line += line_len ) |
| { |
| TT_Int n, width = map->width; |
| TT_Byte old; |
| TT_Byte* cur = line; |
| |
| |
| old = cur[0] << 1; |
| for ( n = 8; n < width; n += 8 ) |
| { |
| TT_Byte val; |
| |
| |
| val = cur[1]; |
| cur[0] = old | (val >> 7); |
| old = 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 |
| { |
| TT_Int right = map->width-1; |
| TT_Byte* limit; |
| TT_Byte mask; |
| |
| |
| line = (TT_Byte*)map->buffer + (right >> 3); |
| limit = line + rows*line_len; |
| mask = 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 |
| TT_Error Load_SBit_Single( FT_Bitmap* map, |
| TT_Int x_offset, |
| TT_Int y_offset, |
| TT_Int pix_bits, |
| TT_UShort image_format, |
| TT_SBit_Metrics* metrics, |
| FT_Stream stream ) |
| { |
| TT_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 = TT_Err_Invalid_Argument; |
| |
| goto Exit; |
| } |
| |
| { |
| TT_Int glyph_width = metrics->width; |
| TT_Int glyph_height = metrics->height; |
| TT_Int glyph_size; |
| TT_Int line_bits = pix_bits * glyph_width; |
| TT_Bool pad_bytes = 0; |
| |
| |
| /* compute size of glyph image */ |
| switch ( image_format ) |
| { |
| case 1: /* byte-padded formats */ |
| case 6: |
| { |
| TT_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 TT_Err_Invalid_File_Format; |
| } |
| |
| /* Now read data and draw glyph into target pixmap */ |
| if ( ACCESS_Frame( 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, stream->cursor, line_bits, pad_bytes, |
| x_offset * pix_bits, y_offset ); |
| |
| FORGET_Frame(); |
| } |
| |
| Exit: |
| return error; |
| } |
| |
| |
| static |
| TT_Error Load_SBit_Image( TT_SBit_Strike* strike, |
| TT_SBit_Range* range, |
| TT_ULong ebdt_pos, |
| TT_ULong glyph_offset, |
| FT_Bitmap* map, |
| TT_Int x_offset, |
| TT_Int y_offset, |
| FT_Stream stream, |
| TT_SBit_Metrics* metrics ) |
| { |
| FT_Memory memory = stream->memory; |
| TT_Error error; |
| |
| |
| /* place stream at beginning of glyph data and read metrics */ |
| if ( FILE_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 ) |
| { |
| TT_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_pal2; |
| map->pitch = (map->width+3) >> 2; |
| break; |
| case 4: |
| map->pixel_mode = ft_pixel_mode_pal4; |
| map->pitch = (map->width+1) >> 1; |
| break; |
| case 8: |
| map->pixel_mode = ft_pixel_mode_grays; |
| map->pitch = map->width; |
| break; |
| |
| default: |
| return TT_Err_Invalid_File_Format; |
| } |
| |
| size = map->rows * map->pitch; |
| |
| /* check that there is no empty image */ |
| if ( size == 0 ) |
| goto Exit; /* exit successfully! */ |
| |
| if ( 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 */ |
| case 9: |
| break; |
| |
| default: /* invalid image format */ |
| return TT_Err_Invalid_File_Format; |
| } |
| |
| /* All right, we're in a compound format. First of all, read */ |
| /* the array of elements */ |
| { |
| TT_SBit_Component* components; |
| TT_SBit_Component* comp; |
| TT_UShort num_components, count; |
| |
| |
| if ( READ_UShort( num_components ) || |
| ALLOC_ARRAY( components, num_components, TT_SBit_Component ) ) |
| goto Exit; |
| |
| count = num_components; |
| |
| if ( ACCESS_Frame( 4L * num_components ) ) |
| goto Fail_Memory; |
| |
| for ( comp = components; count > 0; count--, comp++ ) |
| { |
| comp->glyph_code = GET_UShort(); |
| comp->x_offset = GET_Char(); |
| comp->y_offset = GET_Char(); |
| } |
| |
| FORGET_Frame(); |
| |
| /* Now recursively load each element glyph */ |
| count = num_components; |
| comp = components; |
| for ( ; count > 0; count--, comp++ ) |
| { |
| TT_SBit_Range* elem_range; |
| TT_SBit_Metrics elem_metrics; |
| TT_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: |
| FREE( components ); |
| } |
| |
| Exit: |
| return error; |
| } |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* TT_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. */ |
| /* */ |
| /* x_ppem :: The horizontal resolution in points per EM. */ |
| /* */ |
| /* y_ppem :: The vertical resolution in points per EM. */ |
| /* */ |
| /* glyph_index :: The current glyph index. */ |
| /* */ |
| /* stream :: The input stream. */ |
| /* */ |
| /* <Output> */ |
| /* map :: The target pixmap. */ |
| /* metrics :: A big sbit metrics structure for the glyph image. */ |
| /* */ |
| /* <Return> */ |
| /* TrueType 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. */ |
| /* */ |
| LOCAL_FUNC |
| TT_Error TT_Load_SBit_Image( TT_Face face, |
| TT_Int x_ppem, |
| TT_Int y_ppem, |
| TT_UInt glyph_index, |
| FT_Stream stream, |
| FT_Bitmap* map, |
| TT_SBit_Metrics* metrics ) |
| { |
| TT_Error error; |
| FT_Memory memory = stream->memory; |
| TT_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, x_ppem, y_ppem, |
| &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) goto Exit; |
| |
| ebdt_pos = FILE_Pos(); |
| |
| /* clear the bitmap & load the bitmap */ |
| if (face->root.glyph->flags & ft_glyph_own_bitmap) |
| 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; |
| FT_Int top; |
| |
| |
| advance = strike->hori.ascender - strike->hori.descender; |
| top = advance / 10; |
| |
| metrics->vertBearingX = -metrics->width / 2; |
| metrics->vertBearingY = advance / 10; |
| metrics->vertAdvance = advance * 12 / 10; |
| } |
| |
| /* Crop the bitmap now */ |
| Crop_Bitmap( map, metrics ); |
| |
| Exit: |
| return error; |
| } |
| |
| |
| /* END */ |
