X-Git-Url: http://git.jankratochvil.net/?p=reactos.git;a=blobdiff_plain;f=lib%2Ffreetype%2Fsrc%2Fsfnt%2Fttsbit.c;fp=lib%2Ffreetype%2Fsrc%2Fsfnt%2Fttsbit.c;h=9cfa92be63e6f827fdfd5f83a24f96f843d6541b;hp=0000000000000000000000000000000000000000;hb=7c0db166f81fbe8c8b913d7f26048e337d383605;hpb=e3ed2d773259cc445c7ff8181ebd934931365328 diff --git a/lib/freetype/src/sfnt/ttsbit.c b/lib/freetype/src/sfnt/ttsbit.c new file mode 100644 index 0000000..9cfa92b --- /dev/null +++ b/lib/freetype/src/sfnt/ttsbit.c @@ -0,0 +1,1467 @@ +/***************************************************************************/ +/* */ +/* 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 +#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 + + + /*************************************************************************/ + /* */ + /* */ + /* blit_sbit */ + /* */ + /* */ + /* Blits a bitmap from an input stream into a given target. Supports */ + /* x and y offsets as well as byte padded lines. */ + /* */ + /* */ + /* 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. */ + /* */ + /* */ + /* 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 + }; + + + /*************************************************************************/ + /* */ + /* */ + /* TT_Load_SBit_Const_Metrics */ + /* */ + /* */ + /* Loads the metrics for `EBLC' index tables format 2 and 5. */ + /* */ + /* */ + /* range :: The target range. */ + /* */ + /* stream :: The input stream. */ + /* */ + /* */ + /* 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 ); + } + + + /*************************************************************************/ + /* */ + /* */ + /* TT_Load_SBit_Range_Codes */ + /* */ + /* */ + /* Loads the range codes for `EBLC' index tables format 4 and 5. */ + /* */ + /* */ + /* range :: The target range. */ + /* */ + /* stream :: The input stream. */ + /* */ + /* load_offsets :: A flag whether to load the glyph offset table. */ + /* */ + /* */ + /* 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; + } + + + /*************************************************************************/ + /* */ + /* */ + /* TT_Load_SBit_Range */ + /* */ + /* */ + /* Loads a given `EBLC' index/range table. */ + /* */ + /* */ + /* range :: The target range. */ + /* */ + /* stream :: The input stream. */ + /* */ + /* */ + /* 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; + } + + + /*************************************************************************/ + /* */ + /* */ + /* tt_face_load_sbit_strikes */ + /* */ + /* */ + /* Loads the table of embedded bitmap sizes for this face. */ + /* */ + /* */ + /* face :: The target face object. */ + /* */ + /* stream :: The input stream. */ + /* */ + /* */ + /* 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; + } + + + /*************************************************************************/ + /* */ + /* */ + /* tt_face_free_sbit_strikes */ + /* */ + /* */ + /* Releases the embedded bitmap tables. */ + /* */ + /* */ + /* 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; + } + + + /*************************************************************************/ + /* */ + /* */ + /* find_sbit_range */ + /* */ + /* */ + /* Scans a given strike's ranges and return, for a given glyph */ + /* index, the corresponding sbit range, and `EBDT' offset. */ + /* */ + /* */ + /* glyph_index :: The glyph index. */ + /* */ + /* strike :: The source/current sbit strike. */ + /* */ + /* */ + /* arange :: The sbit range containing the glyph index. */ + /* */ + /* aglyph_offset :: The offset of the glyph data in `EBDT' table. */ + /* */ + /* */ + /* 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; + } + + + /*************************************************************************/ + /* */ + /* */ + /* find_sbit_image */ + /* */ + /* */ + /* Checks whether an embedded bitmap (an `sbit') exists for a given */ + /* glyph, at a given strike. */ + /* */ + /* */ + /* face :: The target face object. */ + /* */ + /* glyph_index :: The glyph index. */ + /* */ + /* strike_index :: The current strike index. */ + /* */ + /* */ + /* 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. */ + /* */ + /* */ + /* 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; + } + + + /*************************************************************************/ + /* */ + /* */ + /* load_sbit_metrics */ + /* */ + /* */ + /* Gets the big metrics for a given SBit. */ + /* */ + /* */ + /* stream :: The input stream. */ + /* */ + /* range :: The SBit range containing the glyph. */ + /* */ + /* */ + /* big_metrics :: A big SBit metrics structure for the glyph. */ + /* */ + /* */ + /* FreeType error code. 0 means success. */ + /* */ + /* */ + /* 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; + } + + + /*************************************************************************/ + /* */ + /* */ + /* crop_bitmap */ + /* */ + /* */ + /* Crops a bitmap to its tightest bounding box, and adjusts its */ + /* metrics. */ + /* */ + /* */ + /* 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_GlyphSlot slot, + FT_Int x_offset, + FT_Int y_offset, + FT_Stream stream, + TT_SBit_Metrics metrics, + FT_Int depth ) + { + FT_Memory memory = stream->memory; + FT_Bitmap* map = &slot->bitmap; + 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, we */ + /* compute the dimensions of the higher-level glyph to */ + /* allocate the final pixmap buffer */ + if ( depth == 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! */ + + error = ft_glyphslot_alloc_bitmap( slot, size ); + if (error) + 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, + slot, + x_offset + comp->x_offset, + y_offset + comp->y_offset, + stream, + &elem_metrics, + depth+1 ); + if ( error ) + goto Fail_Memory; + } + + Fail_Memory: + FT_FREE( components ); + } + + Exit: + return error; + } + + + /*************************************************************************/ + /* */ + /* */ + /* tt_face_load_sbit_image */ + /* */ + /* */ + /* Loads a given glyph sbit image from the font resource. This also */ + /* returns its metrics. */ + /* */ + /* */ + /* 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. */ + /* */ + /* */ + /* map :: The target pixmap. */ + /* */ + /* metrics :: A big sbit metrics structure for the glyph image. */ + /* */ + /* */ + /* FreeType error code. 0 means success. Returns an error if no */ + /* glyph sbit exists for the index. */ + /* */ + /* */ + /* 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_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(); + + error = Load_SBit_Image( strike, range, ebdt_pos, glyph_offset, + face->root.glyph, 0, 0, stream, metrics, 0 ); + if ( error ) + goto Exit; + + /* 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 */