+++ /dev/null
-/***************************************************************************/
-/* */
-/* ttsbit.c */
-/* */
-/* TrueType and OpenType embedded bitmap support (body). */
-/* */
-/* Copyright 1996-2001 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)*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 ( (FT_Int)loaded < count )
- {
- acc |= (FT_UShort)*source++ << ( 8 - loaded );
- loaded += 8;
- }
-
- /* now write remaining bits */
- val = (FT_Byte)( ( (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 = 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_Metrics
-
- 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 ( READ_ULong( range->image_size ) )
- return error;
-
- return 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 ( 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, FT_ULong ) )
- goto Exit;
-
- size = count * 4L;
- }
- else
- size = count * 2L;
-
- /* Allocate glyph codes table and access frame */
- if ( ALLOC_ARRAY ( range->glyph_codes, count, FT_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] = (FT_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> */
- /* 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 ( ALLOC_ARRAY( range->glyph_offsets,
- num_glyphs, FT_ULong ) ||
- ACCESS_Frame( num_glyphs * size_elem ) )
- goto Exit;
-
- for ( n = 0; n < num_glyphs; n++ )
- range->glyph_offsets[n] = (FT_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 = SFNT_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> */
- /* FreeType error code. 0 means success. */
- /* */
- FT_LOCAL_DEF FT_Error
- TT_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_Line_Metrics
-
- /* 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_Strike
-
- /* 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 = 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 != 0x00020000L ||
- num_strikes >= 0x10000L )
- {
- FT_ERROR(( "TT_Load_SBit_Strikes: invalid table version!\n" ));
- error = SFNT_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;
- FT_ULong count = num_strikes;
-
-
- if ( ACCESS_Frame( 48L * num_strikes ) )
- goto Exit;
-
- while ( count > 0 )
- {
- if ( READ_Fields( strike_start_fields, strike ) ||
- READ_Fields( sbit_line_metrics_fields, &strike->hori ) ||
- READ_Fields( sbit_line_metrics_fields, &strike->vert ) ||
- READ_Fields( strike_end_fields, strike ) )
- break;
-
- count--;
- strike++;
- }
-
- FORGET_Frame();
- }
-
- /* 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 ( 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. */
- /* */
- FT_LOCAL_DEF 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;
- }
-
-
- FT_LOCAL_DEF FT_Error
- TT_Set_SBit_Strike( TT_Face face,
- FT_Int x_ppem,
- FT_Int y_ppem,
- FT_ULong *astrike_index )
- {
- FT_Int 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_Range *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 <= (FT_Int)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_Small_Metrics smetrics;
-
- const FT_Frame_Field sbit_small_metrics_fields[] =
- {
-#undef FT_STRUCTURE
-#define FT_STRUCTURE TT_SBit_Small_Metrics
-
- 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 ( 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 ( 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;
-
- 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 ( 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, (FT_Byte*)stream->cursor, line_bits, pad_bytes,
- x_offset * pix_bits, y_offset );
-
- FORGET_Frame();
- }
-
- 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 ( 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 )
- {
- 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_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 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 ( 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_Skip_Stream( 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 ( 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;
- 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:
- 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. */
- /* */
- /* 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_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_Metrics *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 = 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;
-
-
- 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 */
projects / rrdtool.git / blobdiff