?? pfrsbit.c
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/***************************************************************************/
/* */
/* pfrsbit.c */
/* */
/* FreeType PFR bitmap loader (body). */
/* */
/* Copyright 2002, 2003, 2006 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 "pfrsbit.h"
#include "pfrload.h"
#include FT_INTERNAL_DEBUG_H
#include FT_INTERNAL_STREAM_H
#include "pfrerror.h"
#undef FT_COMPONENT
#define FT_COMPONENT trace_pfr
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** PFR BIT WRITER *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
typedef struct PFR_BitWriter_
{
FT_Byte* line; /* current line start */
FT_Int pitch; /* line size in bytes */
FT_Int width; /* width in pixels/bits */
FT_Int rows; /* number of remaining rows to scan */
FT_Int total; /* total number of bits to draw */
} PFR_BitWriterRec, *PFR_BitWriter;
static void
pfr_bitwriter_init( PFR_BitWriter writer,
FT_Bitmap* target,
FT_Bool decreasing )
{
writer->line = target->buffer;
writer->pitch = target->pitch;
writer->width = target->width;
writer->rows = target->rows;
writer->total = writer->width * writer->rows;
if ( !decreasing )
{
writer->line += writer->pitch * ( target->rows-1 );
writer->pitch = -writer->pitch;
}
}
static void
pfr_bitwriter_decode_bytes( PFR_BitWriter writer,
FT_Byte* p,
FT_Byte* limit )
{
FT_Int n, reload;
FT_Int left = writer->width;
FT_Byte* cur = writer->line;
FT_UInt mask = 0x80;
FT_UInt val = 0;
FT_UInt c = 0;
n = (FT_Int)( limit - p ) * 8;
if ( n > writer->total )
n = writer->total;
reload = n & 7;
for ( ; n > 0; n-- )
{
if ( ( n & 7 ) == reload )
val = *p++;
if ( val & 0x80 )
c |= mask;
val <<= 1;
mask >>= 1;
if ( --left <= 0 )
{
cur[0] = (FT_Byte)c;
left = writer->width;
mask = 0x80;
writer->line += writer->pitch;
cur = writer->line;
c = 0;
}
else if ( mask == 0 )
{
cur[0] = (FT_Byte)c;
mask = 0x80;
c = 0;
cur ++;
}
}
if ( mask != 0x80 )
cur[0] = (FT_Byte)c;
}
static void
pfr_bitwriter_decode_rle1( PFR_BitWriter writer,
FT_Byte* p,
FT_Byte* limit )
{
FT_Int n, phase, count, counts[2], reload;
FT_Int left = writer->width;
FT_Byte* cur = writer->line;
FT_UInt mask = 0x80;
FT_UInt c = 0;
n = writer->total;
phase = 1;
counts[0] = 0;
counts[1] = 0;
count = 0;
reload = 1;
for ( ; n > 0; n-- )
{
if ( reload )
{
do
{
if ( phase )
{
FT_Int v;
if ( p >= limit )
break;
v = *p++;
counts[0] = v >> 4;
counts[1] = v & 15;
phase = 0;
count = counts[0];
}
else
{
phase = 1;
count = counts[1];
}
} while ( count == 0 );
}
if ( phase )
c |= mask;
mask >>= 1;
if ( --left <= 0 )
{
cur[0] = (FT_Byte) c;
left = writer->width;
mask = 0x80;
writer->line += writer->pitch;
cur = writer->line;
c = 0;
}
else if ( mask == 0 )
{
cur[0] = (FT_Byte)c;
mask = 0x80;
c = 0;
cur ++;
}
reload = ( --count <= 0 );
}
if ( mask != 0x80 )
cur[0] = (FT_Byte) c;
}
static void
pfr_bitwriter_decode_rle2( PFR_BitWriter writer,
FT_Byte* p,
FT_Byte* limit )
{
FT_Int n, phase, count, reload;
FT_Int left = writer->width;
FT_Byte* cur = writer->line;
FT_UInt mask = 0x80;
FT_UInt c = 0;
n = writer->total;
phase = 1;
count = 0;
reload = 1;
for ( ; n > 0; n-- )
{
if ( reload )
{
do
{
if ( p >= limit )
break;
count = *p++;
phase = phase ^ 1;
} while ( count == 0 );
}
if ( phase )
c |= mask;
mask >>= 1;
if ( --left <= 0 )
{
cur[0] = (FT_Byte) c;
c = 0;
mask = 0x80;
left = writer->width;
writer->line += writer->pitch;
cur = writer->line;
}
else if ( mask == 0 )
{
cur[0] = (FT_Byte)c;
c = 0;
mask = 0x80;
cur ++;
}
reload = ( --count <= 0 );
}
if ( mask != 0x80 )
cur[0] = (FT_Byte) c;
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** BITMAP DATA DECODING *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
static void
pfr_lookup_bitmap_data( FT_Byte* base,
FT_Byte* limit,
FT_UInt count,
FT_UInt flags,
FT_UInt char_code,
FT_ULong* found_offset,
FT_ULong* found_size )
{
FT_UInt left, right, char_len;
FT_Bool two = FT_BOOL( flags & 1 );
FT_Byte* buff;
char_len = 4;
if ( two ) char_len += 1;
if ( flags & 2 ) char_len += 1;
if ( flags & 4 ) char_len += 1;
left = 0;
right = count;
while ( left < right )
{
FT_UInt middle, code;
middle = ( left + right ) >> 1;
buff = base + middle * char_len;
/* check that we are not outside of the table -- */
/* this is possible with broken fonts... */
if ( buff + char_len > limit )
goto Fail;
if ( two )
code = PFR_NEXT_USHORT( buff );
else
code = PFR_NEXT_BYTE( buff );
if ( code == char_code )
goto Found_It;
if ( code < char_code )
left = middle;
else
right = middle;
}
Fail:
/* Not found */
*found_size = 0;
*found_offset = 0;
return;
Found_It:
if ( flags & 2 )
*found_size = PFR_NEXT_USHORT( buff );
else
*found_size = PFR_NEXT_BYTE( buff );
if ( flags & 4 )
*found_offset = PFR_NEXT_ULONG( buff );
else
*found_offset = PFR_NEXT_USHORT( buff );
}
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