--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/misc/libfreetype/src/sfnt/ttsbit.c Mon Apr 25 01:46:54 2011 +0200
@@ -0,0 +1,1508 @@
+/***************************************************************************/
+/* */
+/* ttsbit.c */
+/* */
+/* TrueType and OpenType embedded bitmap support (body). */
+/* */
+/* Copyright 1996-2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, */
+/* 2010 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
+
+ /*
+ * Alas, the memory-optimized sbit loader can't be used when implementing
+ * the `old internals' hack
+ */
+#ifndef FT_CONFIG_OPTION_OLD_INTERNALS
+
+#include "ttsbit0.c"
+
+#else /* FT_CONFIG_OPTION_OLD_INTERNALS */
+
+#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_Int source_height )
+ {
+ 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 = source_height; 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;
+ }
+ }
+
+
+ static const FT_Frame_Field sbit_metrics_fields[] =
+ {
+#undef FT_STRUCTURE
+#define FT_STRUCTURE TT_SBit_MetricsRec
+
+ FT_FRAME_START( 8 ),
+ FT_FRAME_BYTE( height ),
+ FT_FRAME_BYTE( width ),
+
+ FT_FRAME_CHAR( horiBearingX ),
+ FT_FRAME_CHAR( horiBearingY ),
+ FT_FRAME_BYTE( horiAdvance ),
+
+ FT_FRAME_CHAR( vertBearingX ),
+ FT_FRAME_CHAR( vertBearingY ),
+ FT_FRAME_BYTE( vertAdvance ),
+ FT_FRAME_END
+ };
+
+
+ /*************************************************************************/
+ /* */
+ /* <Function> */
+ /* Load_SBit_Const_Metrics */
+ /* */
+ /* <Description> */
+ /* Loads the metrics for `EBLC' index tables format 2 and 5. */
+ /* */
+ /* <Input> */
+ /* range :: The target range. */
+ /* */
+ /* stream :: The input stream. */
+ /* */
+ /* <Return> */
+ /* FreeType error code. 0 means success. */
+ /* */
+ static FT_Error
+ Load_SBit_Const_Metrics( TT_SBit_Range range,
+ FT_Stream stream )
+ {
+ FT_Error error;
+
+
+ if ( FT_READ_ULONG( range->image_size ) )
+ return error;
+
+ return FT_STREAM_READ_FIELDS( sbit_metrics_fields, &range->metrics );
+ }
+
+
+ /*************************************************************************/
+ /* */
+ /* <Function> */
+ /* Load_SBit_Range_Codes */
+ /* */
+ /* <Description> */
+ /* Loads the range codes for `EBLC' index tables format 4 and 5. */
+ /* */
+ /* <Input> */
+ /* range :: The target range. */
+ /* */
+ /* stream :: The input stream. */
+ /* */
+ /* load_offsets :: A flag whether to load the glyph offset table. */
+ /* */
+ /* <Return> */
+ /* FreeType error code. 0 means success. */
+ /* */
+ static FT_Error
+ Load_SBit_Range_Codes( TT_SBit_Range range,
+ FT_Stream stream,
+ FT_Bool load_offsets )
+ {
+ FT_Error error;
+ FT_ULong count, n, size;
+ FT_Memory memory = stream->memory;
+
+
+ if ( FT_READ_ULONG( count ) )
+ goto Exit;
+
+ range->num_glyphs = count;
+
+ /* Allocate glyph offsets table if needed */
+ if ( load_offsets )
+ {
+ if ( FT_NEW_ARRAY( range->glyph_offsets, count ) )
+ goto Exit;
+
+ size = count * 4L;
+ }
+ else
+ size = count * 2L;
+
+ /* Allocate glyph codes table and access frame */
+ if ( FT_NEW_ARRAY ( range->glyph_codes, count ) ||
+ FT_FRAME_ENTER( size ) )
+ goto Exit;
+
+ for ( n = 0; n < count; n++ )
+ {
+ range->glyph_codes[n] = FT_GET_USHORT();
+
+ if ( load_offsets )
+ range->glyph_offsets[n] = (FT_ULong)range->image_offset +
+ FT_GET_USHORT();
+ }
+
+ FT_FRAME_EXIT();
+
+ Exit:
+ return error;
+ }
+
+
+ /*************************************************************************/
+ /* */
+ /* <Function> */
+ /* 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 );
+
+
+
+ if ( range->last_glyph < range->first_glyph )
+ {
+ error = SFNT_Err_Invalid_File_Format;
+ goto Exit;
+ }
+
+ 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 );
+ if ( !error )
+ error = Load_SBit_Range_Codes( range, stream, 0 );
+ break;
+
+ default:
+ error = SFNT_Err_Invalid_File_Format;
+ }
+
+ Exit:
+ return error;
+ }
+
+
+ /*************************************************************************/
+ /* */
+ /* <Function> */
+ /* tt_face_load_eblc */
+ /* */
+ /* <Description> */
+ /* Loads the table of embedded bitmap sizes for this face. */
+ /* */
+ /* <Input> */
+ /* face :: The target face object. */
+ /* */
+ /* stream :: The input stream. */
+ /* */
+ /* <Return> */
+ /* FreeType error code. 0 means success. */
+ /* */
+ FT_LOCAL_DEF( FT_Error )
+ tt_face_load_eblc( TT_Face face,
+ FT_Stream stream )
+ {
+ FT_Error error = SFNT_Err_Ok;
+ FT_Memory memory = stream->memory;
+ FT_Fixed version;
+ FT_ULong num_strikes;
+ FT_ULong table_base;
+
+ static 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
+ };
+
+ static 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
+ };
+
+ static 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;
+
+
+ /* read each range */
+ if ( FT_STREAM_SEEK( table_base + strike->ranges_offset ) ||
+ FT_FRAME_ENTER( strike->num_ranges * 8L ) )
+ goto Exit;
+
+ if ( FT_NEW_ARRAY( strike->sbit_ranges, strike->num_ranges ) )
+ goto Exit;
+
+ range = strike->sbit_ranges;
+ while ( count2 > 0 )
+ {
+ range->first_glyph = FT_GET_USHORT();
+ range->last_glyph = FT_GET_USHORT();
+ range->table_offset = table_base + strike->ranges_offset +
+ FT_GET_ULONG();
+ count2--;
+ range++;
+ }
+
+ FT_FRAME_EXIT();
+
+ /* Now, read each index table */
+ count2 = strike->num_ranges;
+ range = strike->sbit_ranges;
+ while ( count2 > 0 )
+ {
+ /* Read the header */
+ if ( FT_STREAM_SEEK( range->table_offset ) ||
+ FT_FRAME_ENTER( 8L ) )
+ goto Exit;
+
+ range->index_format = FT_GET_USHORT();
+ range->image_format = FT_GET_USHORT();
+ range->image_offset = FT_GET_ULONG();
+
+ FT_FRAME_EXIT();
+
+ error = Load_SBit_Range( range, stream );
+ if ( error )
+ goto Exit;
+
+ count2--;
+ range++;
+ }
+
+ count--;
+ strike++;
+ }
+ }
+
+ Exit:
+ return error;
+ }
+
+
+ /*************************************************************************/
+ /* */
+ /* <Function> */
+ /* tt_face_free_eblc */
+ /* */
+ /* <Description> */
+ /* Releases the embedded bitmap tables. */
+ /* */
+ /* <Input> */
+ /* face :: The target face object. */
+ /* */
+ FT_LOCAL_DEF( void )
+ tt_face_free_eblc( 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_Size_Request req,
+ FT_ULong* astrike_index )
+ {
+ return FT_Match_Size( (FT_Face)face, req, 0, astrike_index );
+ }
+
+
+ FT_LOCAL_DEF( FT_Error )
+ tt_face_load_strike_metrics( TT_Face face,
+ FT_ULong strike_index,
+ FT_Size_Metrics* metrics )
+ {
+ TT_SBit_Strike strike;
+
+
+ if ( strike_index >= face->num_sbit_strikes )
+ return SFNT_Err_Invalid_Argument;
+
+ strike = face->sbit_strikes + strike_index;
+
+ metrics->x_ppem = strike->x_ppem;
+ metrics->y_ppem = strike->y_ppem;
+
+ metrics->ascender = strike->hori.ascender << 6;
+ metrics->descender = strike->hori.descender << 6;
+
+ /* XXX: Is this correct? */
+ metrics->max_advance = ( strike->hori.min_origin_SB +
+ strike->hori.max_width +
+ strike->hori.min_advance_SB ) << 6;
+
+ metrics->height = metrics->ascender - metrics->descender;
+
+ return SFNT_Err_Ok;
+ }
+
+
+ /*************************************************************************/
+ /* */
+ /* <Function> */
+ /* find_sbit_range */
+ /* */
+ /* <Description> */
+ /* Scans a given strike's ranges and return, for a given glyph */
+ /* index, the corresponding sbit range, and `EBDT' offset. */
+ /* */
+ /* <Input> */
+ /* glyph_index :: The glyph index. */
+ /* */
+ /* strike :: The source/current sbit strike. */
+ /* */
+ /* <Output> */
+ /* arange :: The sbit range containing the glyph index. */
+ /* */
+ /* aglyph_offset :: The offset of the glyph data in `EBDT' table. */
+ /* */
+ /* <Return> */
+ /* FreeType error code. 0 means the glyph index was found. */
+ /* */
+ static FT_Error
+ find_sbit_range( FT_UInt glyph_index,
+ TT_SBit_Strike strike,
+ TT_SBit_Range *arange,
+ FT_ULong *aglyph_offset )
+ {
+ TT_SBit_RangeRec *range, *range_limit;
+
+
+ /* check whether the glyph index is within this strike's */
+ /* glyph range */
+ if ( glyph_index < (FT_UInt)strike->start_glyph ||
+ glyph_index > (FT_UInt)strike->end_glyph )
+ goto Fail;
+
+ /* scan all ranges in strike */
+ range = strike->sbit_ranges;
+ range_limit = range + strike->num_ranges;
+ if ( !range )
+ goto Fail;
+
+ for ( ; range < range_limit; range++ )
+ {
+ if ( glyph_index >= (FT_UInt)range->first_glyph &&
+ glyph_index <= (FT_UInt)range->last_glyph )
+ {
+ FT_UShort delta = (FT_UShort)( glyph_index - range->first_glyph );
+
+
+ switch ( range->index_format )
+ {
+ case 1:
+ case 3:
+ *aglyph_offset = range->glyph_offsets[delta];
+ break;
+
+ case 2:
+ *aglyph_offset = range->image_offset +
+ range->image_size * delta;
+ break;
+
+ case 4:
+ case 5:
+ {
+ FT_ULong n;
+
+
+ for ( n = 0; n < range->num_glyphs; n++ )
+ {
+ if ( (FT_UInt)range->glyph_codes[n] == glyph_index )
+ {
+ if ( range->index_format == 4 )
+ *aglyph_offset = range->glyph_offsets[n];
+ else
+ *aglyph_offset = range->image_offset +
+ n * range->image_size;
+ goto Found;
+ }
+ }
+ }
+
+ /* fall-through */
+ default:
+ goto Fail;
+ }
+
+ Found:
+ /* return successfully! */
+ *arange = range;
+ return SFNT_Err_Ok;
+ }
+ }
+
+ Fail:
+ *arange = 0;
+ *aglyph_offset = 0;
+
+ return SFNT_Err_Invalid_Argument;
+ }
+
+
+ /*************************************************************************/
+ /* */
+ /* <Function> */
+ /* tt_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. */
+ /* */
+ FT_LOCAL( FT_Error )
+ tt_find_sbit_image( TT_Face face,
+ FT_UInt glyph_index,
+ FT_ULong strike_index,
+ TT_SBit_Range *arange,
+ TT_SBit_Strike *astrike,
+ FT_ULong *aglyph_offset )
+ {
+ FT_Error error;
+ TT_SBit_Strike strike;
+
+
+ if ( !face->sbit_strikes ||
+ ( face->num_sbit_strikes <= strike_index ) )
+ goto Fail;
+
+ strike = &face->sbit_strikes[strike_index];
+
+ error = find_sbit_range( glyph_index, strike,
+ arange, aglyph_offset );
+ if ( error )
+ goto Fail;
+
+ *astrike = strike;
+
+ return SFNT_Err_Ok;
+
+ Fail:
+ /* no embedded bitmap for this glyph in face */
+ *arange = 0;
+ *astrike = 0;
+ *aglyph_offset = 0;
+
+ return SFNT_Err_Invalid_Argument;
+ }
+
+
+ /*************************************************************************/
+ /* */
+ /* <Function> */
+ /* tt_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. */
+ /* */
+ FT_LOCAL( FT_Error )
+ tt_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;
+
+ static const FT_Frame_Field sbit_small_metrics_fields[] =
+ {
+#undef FT_STRUCTURE
+#define FT_STRUCTURE TT_SBit_SmallMetricsRec
+
+ FT_FRAME_START( 5 ),
+ FT_FRAME_BYTE( height ),
+ FT_FRAME_BYTE( width ),
+ FT_FRAME_CHAR( bearingX ),
+ FT_FRAME_CHAR( bearingY ),
+ FT_FRAME_BYTE( advance ),
+ FT_FRAME_END
+ };
+
+
+ /* read small metrics */
+ if ( FT_STREAM_READ_FIELDS( sbit_small_metrics_fields, &smetrics ) )
+ goto Exit;
+
+ /* convert it to a big metrics */
+ metrics->height = smetrics.height;
+ metrics->width = smetrics.width;
+ metrics->horiBearingX = smetrics.bearingX;
+ metrics->horiBearingY = smetrics.bearingY;
+ metrics->horiAdvance = smetrics.advance;
+
+ /* these metrics are made up at a higher level when */
+ /* needed. */
+ metrics->vertBearingX = 0;
+ metrics->vertBearingY = 0;
+ metrics->vertAdvance = 0;
+ }
+ break;
+
+ case 6:
+ case 7:
+ case 9:
+ /* variable big metrics */
+ if ( FT_STREAM_READ_FIELDS( sbit_metrics_fields, metrics ) )
+ goto Exit;
+ break;
+
+ case 5:
+ default: /* constant metrics */
+ if ( range->index_format == 2 || range->index_format == 5 )
+ *metrics = range->metrics;
+ else
+ return SFNT_Err_Invalid_File_Format;
+ }
+
+ Exit:
+ return error;
+ }
+
+
+ /*************************************************************************/
+ /* */
+ /* <Function> */
+ /* crop_bitmap */
+ /* */
+ /* <Description> */
+ /* Crops a bitmap to its tightest bounding box, and adjusts its */
+ /* metrics. */
+ /* */
+ /* <InOut> */
+ /* map :: The bitmap. */
+ /* */
+ /* metrics :: The corresponding metrics structure. */
+ /* */
+ static void
+ crop_bitmap( FT_Bitmap* map,
+ TT_SBit_Metrics metrics )
+ {
+ /***********************************************************************/
+ /* */
+ /* In this situation, some bounding boxes of embedded bitmaps are too */
+ /* large. We need to crop it to a reasonable size. */
+ /* */
+ /* --------- */
+ /* | | ----- */
+ /* | *** | |***| */
+ /* | * | | * | */
+ /* | * | ------> | * | */
+ /* | * | | * | */
+ /* | * | | * | */
+ /* | *** | |***| */
+ /* --------- ----- */
+ /* */
+ /***********************************************************************/
+
+ FT_Int rows, count;
+ FT_Long line_len;
+ FT_Byte* line;
+
+
+ /***********************************************************************/
+ /* */
+ /* first of all, check the top-most lines of the bitmap, and remove */
+ /* them if they're empty. */
+ /* */
+ {
+ line = (FT_Byte*)map->buffer;
+ rows = map->rows;
+ line_len = map->pitch;
+
+
+ for ( count = 0; count < rows; count++ )
+ {
+ FT_Byte* cur = line;
+ FT_Byte* limit = line + line_len;
+
+
+ for ( ; cur < limit; cur++ )
+ if ( cur[0] )
+ goto Found_Top;
+
+ /* the current line was empty - skip to next one */
+ line = limit;
+ }
+
+ Found_Top:
+ /* check that we have at least one filled line */
+ if ( count >= rows )
+ goto Empty_Bitmap;
+
+ /* now, crop the empty upper lines */
+ if ( count > 0 )
+ {
+ line = (FT_Byte*)map->buffer;
+
+ FT_MEM_MOVE( line, line + count * line_len,
+ ( rows - count ) * line_len );
+
+ metrics->height = (FT_Byte)( metrics->height - count );
+ metrics->horiBearingY = (FT_Char)( metrics->horiBearingY - count );
+ metrics->vertBearingY = (FT_Char)( metrics->vertBearingY - count );
+
+ map->rows -= count;
+ rows -= count;
+ }
+ }
+
+ /***********************************************************************/
+ /* */
+ /* second, crop the lower lines */
+ /* */
+ {
+ line = (FT_Byte*)map->buffer + ( rows - 1 ) * line_len;
+
+ for ( count = 0; count < rows; count++ )
+ {
+ FT_Byte* cur = line;
+ FT_Byte* limit = line + line_len;
+
+
+ for ( ; cur < limit; cur++ )
+ if ( cur[0] )
+ goto Found_Bottom;
+
+ /* the current line was empty - skip to previous one */
+ line -= line_len;
+ }
+
+ Found_Bottom:
+ if ( count > 0 )
+ {
+ metrics->height = (FT_Byte)( metrics->height - count );
+ rows -= count;
+ map->rows -= count;
+ }
+ }
+
+ /***********************************************************************/
+ /* */
+ /* third, get rid of the space on the left side of the glyph */
+ /* */
+ do
+ {
+ FT_Byte* limit;
+
+
+ line = (FT_Byte*)map->buffer;
+ limit = line + rows * line_len;
+
+ for ( ; line < limit; line += line_len )
+ if ( line[0] & 0x80 )
+ goto Found_Left;
+
+ /* shift the whole glyph one pixel to the left */
+ line = (FT_Byte*)map->buffer;
+ limit = line + rows * line_len;
+
+ for ( ; line < limit; line += line_len )
+ {
+ FT_Int n, width = map->width;
+ FT_Byte old;
+ FT_Byte* cur = line;
+
+
+ old = (FT_Byte)(cur[0] << 1);
+ for ( n = 8; n < width; n += 8 )
+ {
+ FT_Byte val;
+
+
+ val = cur[1];
+ cur[0] = (FT_Byte)( old | ( val >> 7 ) );
+ old = (FT_Byte)( val << 1 );
+ cur++;
+ }
+ cur[0] = old;
+ }
+
+ map->width--;
+ metrics->horiBearingX++;
+ metrics->vertBearingX++;
+ metrics->width--;
+
+ } while ( map->width > 0 );
+
+ Found_Left:
+
+ /***********************************************************************/
+ /* */
+ /* finally, crop the bitmap width to get rid of the space on the right */
+ /* side of the glyph. */
+ /* */
+ do
+ {
+ FT_Int right = map->width - 1;
+ FT_Byte* limit;
+ FT_Byte mask;
+
+
+ line = (FT_Byte*)map->buffer + ( right >> 3 );
+ limit = line + rows * line_len;
+ mask = (FT_Byte)( 0x80 >> ( right & 7 ) );
+
+ for ( ; line < limit; line += line_len )
+ if ( line[0] & mask )
+ goto Found_Right;
+
+ /* crop the whole glyph to the right */
+ map->width--;
+ metrics->width--;
+
+ } while ( map->width > 0 );
+
+ Found_Right:
+ /* all right, the bitmap was cropped */
+ return;
+
+ Empty_Bitmap:
+ map->width = 0;
+ map->rows = 0;
+ map->pitch = 0;
+ map->pixel_mode = FT_PIXEL_MODE_MONO;
+ }
+
+
+ static FT_Error
+ Load_SBit_Single( FT_Bitmap* map,
+ FT_Int x_offset,
+ FT_Int y_offset,
+ FT_Int pix_bits,
+ FT_UShort image_format,
+ TT_SBit_Metrics metrics,
+ FT_Stream stream )
+ {
+ FT_Error error;
+
+
+ /* check that the source bitmap fits into the target pixmap */
+ if ( x_offset < 0 || x_offset + metrics->width > map->width ||
+ y_offset < 0 || y_offset + metrics->height > map->rows )
+ {
+ error = SFNT_Err_Invalid_Argument;
+
+ goto Exit;
+ }
+
+ {
+ FT_Int glyph_width = metrics->width;
+ FT_Int glyph_height = metrics->height;
+ FT_Int glyph_size;
+ FT_Int line_bits = pix_bits * glyph_width;
+ FT_Bool pad_bytes = 0;
+
+
+ /* compute size of glyph image */
+ switch ( image_format )
+ {
+ case 1: /* byte-padded formats */
+ case 6:
+ {
+ FT_Int line_length;
+
+
+ switch ( pix_bits )
+ {
+ case 1:
+ line_length = ( glyph_width + 7 ) >> 3;
+ break;
+ case 2:
+ line_length = ( glyph_width + 3 ) >> 2;
+ break;
+ case 4:
+ line_length = ( glyph_width + 1 ) >> 1;
+ break;
+ default:
+ line_length = glyph_width;
+ }
+
+ glyph_size = glyph_height * line_length;
+ pad_bytes = 1;
+ }
+ break;
+
+ case 2:
+ case 5:
+ case 7:
+ line_bits = glyph_width * pix_bits;
+ glyph_size = ( glyph_height * line_bits + 7 ) >> 3;
+ break;
+
+ default: /* invalid format */
+ return SFNT_Err_Invalid_File_Format;
+ }
+
+ /* Now read data and draw glyph into target pixmap */
+ if ( FT_FRAME_ENTER( glyph_size ) )
+ goto Exit;
+
+ /* don't forget to multiply `x_offset' by `map->pix_bits' as */
+ /* the sbit blitter doesn't make a difference between pixmap */
+ /* depths. */
+ blit_sbit( map, (FT_Byte*)stream->cursor, line_bits, pad_bytes,
+ x_offset * pix_bits, y_offset, metrics->height );
+
+ 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 = tt_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 */
+ if ( FT_STREAM_SKIP( 1L ) )
+ {
+ error = SFNT_Err_Invalid_Stream_Skip;
+ goto Exit;
+ }
+ /* 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;
+ }
+
+
+ /*************************************************************************/
+ /* */
+ /* <Function> */
+ /* tt_face_load_sbit_image */
+ /* */
+ /* <Description> */
+ /* Loads a given glyph sbit image from the font resource. This also */
+ /* returns its metrics. */
+ /* */
+ /* <Input> */
+ /* face :: The target face object. */
+ /* */
+ /* strike_index :: The current strike index. */
+ /* */
+ /* glyph_index :: The current glyph index. */
+ /* */
+ /* load_flags :: The glyph load flags (the code checks for the flag */
+ /* FT_LOAD_CROP_BITMAP). */
+ /* */
+ /* stream :: The input stream. */
+ /* */
+ /* <Output> */
+ /* map :: The target pixmap. */
+ /* */
+ /* metrics :: A big sbit metrics structure for the glyph image. */
+ /* */
+ /* <Return> */
+ /* FreeType error code. 0 means success. Returns an error if no */
+ /* glyph sbit exists for the index. */
+ /* */
+ /* <Note> */
+ /* The `map.buffer' field is always freed before the glyph is loaded. */
+ /* */
+ FT_LOCAL_DEF( FT_Error )
+ tt_face_load_sbit_image( TT_Face face,
+ FT_ULong strike_index,
+ FT_UInt glyph_index,
+ FT_UInt load_flags,
+ FT_Stream stream,
+ FT_Bitmap *map,
+ TT_SBit_MetricsRec *metrics )
+ {
+ FT_Error error;
+ FT_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 = tt_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 - metrics->height ) / 2 );
+ 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;
+ }
+
+#endif /* FT_CONFIG_OPTION_OLD_INTERNALS */
+
+
+/* END */