| /**************************************************************************** |
| * |
| * pfrsbit.c |
| * |
| * FreeType PFR bitmap loader (body). |
| * |
| * Copyright (C) 2002-2021 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 <freetype/internal/ftdebug.h> |
| #include <freetype/internal/ftstream.h> |
| |
| #include "pfrerror.h" |
| |
| #undef FT_COMPONENT |
| #define FT_COMPONENT pfr |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** PFR BIT WRITER *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| typedef struct PFR_BitWriter_ |
| { |
| FT_Byte* line; /* current line start */ |
| FT_Int pitch; /* line size in bytes */ |
| FT_UInt width; /* width in pixels/bits */ |
| FT_UInt rows; /* number of remaining rows to scan */ |
| FT_UInt 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 * (FT_Int)( target->rows - 1 ); |
| writer->pitch = -writer->pitch; |
| } |
| } |
| |
| |
| static void |
| pfr_bitwriter_decode_bytes( PFR_BitWriter writer, |
| FT_Byte* p, |
| FT_Byte* limit ) |
| { |
| FT_UInt n, reload; |
| FT_UInt left = writer->width; |
| FT_Byte* cur = writer->line; |
| FT_UInt mask = 0x80; |
| FT_UInt val = 0; |
| FT_UInt c = 0; |
| |
| |
| n = (FT_UInt)( 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 phase, count, counts[2]; |
| FT_UInt n, reload; |
| FT_UInt 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 phase, count; |
| FT_UInt n, reload; |
| FT_UInt 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 min, max, char_len; |
| FT_Bool two = FT_BOOL( *flags & PFR_BITMAP_2BYTE_CHARCODE ); |
| FT_Byte* buff; |
| |
| |
| char_len = 4; |
| if ( two ) |
| char_len += 1; |
| if ( *flags & PFR_BITMAP_2BYTE_SIZE ) |
| char_len += 1; |
| if ( *flags & PFR_BITMAP_3BYTE_OFFSET ) |
| char_len += 1; |
| |
| if ( !( *flags & PFR_BITMAP_CHARCODES_VALIDATED ) ) |
| { |
| FT_Byte* p; |
| FT_Byte* lim; |
| FT_UInt code; |
| FT_Long prev_code; |
| |
| |
| *flags |= PFR_BITMAP_VALID_CHARCODES; |
| prev_code = -1; |
| lim = base + count * char_len; |
| |
| if ( lim > limit ) |
| { |
| FT_TRACE0(( "pfr_lookup_bitmap_data:" |
| " number of bitmap records too large,\n" )); |
| FT_TRACE0(( " " |
| " thus ignoring all bitmaps in this strike\n" )); |
| *flags &= ~PFR_BITMAP_VALID_CHARCODES; |
| } |
| else |
| { |
| /* check whether records are sorted by code */ |
| for ( p = base; p < lim; p += char_len ) |
| { |
| if ( two ) |
| code = FT_PEEK_USHORT( p ); |
| else |
| code = *p; |
| |
| if ( (FT_Long)code <= prev_code ) |
| { |
| FT_TRACE0(( "pfr_lookup_bitmap_data:" |
| " bitmap records are not sorted,\n" )); |
| FT_TRACE0(( " " |
| " thus ignoring all bitmaps in this strike\n" )); |
| *flags &= ~PFR_BITMAP_VALID_CHARCODES; |
| break; |
| } |
| |
| prev_code = code; |
| } |
| } |
| |
| *flags |= PFR_BITMAP_CHARCODES_VALIDATED; |
| } |
| |
| /* ignore bitmaps in case table is not valid */ |
| /* (this might be sanitized, but PFR is dead...) */ |
| if ( !( *flags & PFR_BITMAP_VALID_CHARCODES ) ) |
| goto Fail; |
| |
| min = 0; |
| max = count; |
| |
| /* binary search */ |
| while ( min < max ) |
| { |
| FT_UInt mid, code; |
| |
| |
| mid = ( min + max ) >> 1; |
| buff = base + mid * char_len; |
| |
| if ( two ) |
| code = PFR_NEXT_USHORT( buff ); |
| else |
| code = PFR_NEXT_BYTE( buff ); |
| |
| if ( char_code < code ) |
| max = mid; |
| else if ( char_code > code ) |
| min = mid + 1; |
| else |
| goto Found_It; |
| } |
| |
| Fail: |
| /* Not found */ |
| *found_size = 0; |
| *found_offset = 0; |
| return; |
| |
| Found_It: |
| if ( *flags & PFR_BITMAP_2BYTE_SIZE ) |
| *found_size = PFR_NEXT_USHORT( buff ); |
| else |
| *found_size = PFR_NEXT_BYTE( buff ); |
| |
| if ( *flags & PFR_BITMAP_3BYTE_OFFSET ) |
| *found_offset = PFR_NEXT_ULONG( buff ); |
| else |
| *found_offset = PFR_NEXT_USHORT( buff ); |
| } |
| |
| |
| /* load bitmap metrics. `*padvance' must be set to the default value */ |
| /* before calling this function */ |
| /* */ |
| static FT_Error |
| pfr_load_bitmap_metrics( FT_Byte** pdata, |
| FT_Byte* limit, |
| FT_Long scaled_advance, |
| FT_Long *axpos, |
| FT_Long *aypos, |
| FT_UInt *axsize, |
| FT_UInt *aysize, |
| FT_Long *aadvance, |
| FT_UInt *aformat ) |
| { |
| FT_Error error = FT_Err_Ok; |
| FT_Byte flags; |
| FT_Byte b; |
| FT_Byte* p = *pdata; |
| FT_Long xpos, ypos, advance; |
| FT_UInt xsize, ysize; |
| |
| |
| PFR_CHECK( 1 ); |
| flags = PFR_NEXT_BYTE( p ); |
| |
| xpos = 0; |
| ypos = 0; |
| xsize = 0; |
| ysize = 0; |
| advance = 0; |
| |
| switch ( flags & 3 ) |
| { |
| case 0: |
| PFR_CHECK( 1 ); |
| b = PFR_NEXT_BYTE( p ); |
| xpos = (FT_Char)b >> 4; |
| ypos = ( (FT_Char)( b << 4 ) ) >> 4; |
| break; |
| |
| case 1: |
| PFR_CHECK( 2 ); |
| xpos = PFR_NEXT_INT8( p ); |
| ypos = PFR_NEXT_INT8( p ); |
| break; |
| |
| case 2: |
| PFR_CHECK( 4 ); |
| xpos = PFR_NEXT_SHORT( p ); |
| ypos = PFR_NEXT_SHORT( p ); |
| break; |
| |
| case 3: |
| PFR_CHECK( 6 ); |
| xpos = PFR_NEXT_LONG( p ); |
| ypos = PFR_NEXT_LONG( p ); |
| break; |
| |
| default: |
| ; |
| } |
| |
| flags >>= 2; |
| switch ( flags & 3 ) |
| { |
| case 0: |
| /* blank image */ |
| xsize = 0; |
| ysize = 0; |
| break; |
| |
| case 1: |
| PFR_CHECK( 1 ); |
| b = PFR_NEXT_BYTE( p ); |
| xsize = ( b >> 4 ) & 0xF; |
| ysize = b & 0xF; |
| break; |
| |
| case 2: |
| PFR_CHECK( 2 ); |
| xsize = PFR_NEXT_BYTE( p ); |
| ysize = PFR_NEXT_BYTE( p ); |
| break; |
| |
| case 3: |
| PFR_CHECK( 4 ); |
| xsize = PFR_NEXT_USHORT( p ); |
| ysize = PFR_NEXT_USHORT( p ); |
| break; |
| |
| default: |
| ; |
| } |
| |
| flags >>= 2; |
| switch ( flags & 3 ) |
| { |
| case 0: |
| advance = scaled_advance; |
| break; |
| |
| case 1: |
| PFR_CHECK( 1 ); |
| advance = PFR_NEXT_INT8( p ) * 256; |
| break; |
| |
| case 2: |
| PFR_CHECK( 2 ); |
| advance = PFR_NEXT_SHORT( p ); |
| break; |
| |
| case 3: |
| PFR_CHECK( 3 ); |
| advance = PFR_NEXT_LONG( p ); |
| break; |
| |
| default: |
| ; |
| } |
| |
| *axpos = xpos; |
| *aypos = ypos; |
| *axsize = xsize; |
| *aysize = ysize; |
| *aadvance = advance; |
| *aformat = flags >> 2; |
| *pdata = p; |
| |
| Exit: |
| return error; |
| |
| Too_Short: |
| error = FT_THROW( Invalid_Table ); |
| FT_ERROR(( "pfr_load_bitmap_metrics: invalid glyph data\n" )); |
| goto Exit; |
| } |
| |
| |
| static FT_Error |
| pfr_load_bitmap_bits( FT_Byte* p, |
| FT_Byte* limit, |
| FT_UInt format, |
| FT_Bool decreasing, |
| FT_Bitmap* target ) |
| { |
| FT_Error error = FT_Err_Ok; |
| PFR_BitWriterRec writer; |
| |
| |
| if ( target->rows > 0 && target->width > 0 ) |
| { |
| pfr_bitwriter_init( &writer, target, decreasing ); |
| |
| switch ( format ) |
| { |
| case 0: /* packed bits */ |
| pfr_bitwriter_decode_bytes( &writer, p, limit ); |
| break; |
| |
| case 1: /* RLE1 */ |
| pfr_bitwriter_decode_rle1( &writer, p, limit ); |
| break; |
| |
| case 2: /* RLE2 */ |
| pfr_bitwriter_decode_rle2( &writer, p, limit ); |
| break; |
| |
| default: |
| ; |
| } |
| } |
| |
| return error; |
| } |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** BITMAP LOADING *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| FT_LOCAL( FT_Error ) |
| pfr_slot_load_bitmap( PFR_Slot glyph, |
| PFR_Size size, |
| FT_UInt glyph_index, |
| FT_Bool metrics_only ) |
| { |
| FT_Error error; |
| PFR_Face face = (PFR_Face) glyph->root.face; |
| FT_Stream stream = face->root.stream; |
| PFR_PhyFont phys = &face->phy_font; |
| FT_ULong gps_offset; |
| FT_ULong gps_size; |
| PFR_Char character; |
| PFR_Strike strike; |
| |
| |
| character = &phys->chars[glyph_index]; |
| |
| /* look up a bitmap strike corresponding to the current */ |
| /* character dimensions */ |
| { |
| FT_UInt n; |
| |
| |
| strike = phys->strikes; |
| for ( n = 0; n < phys->num_strikes; n++ ) |
| { |
| if ( strike->x_ppm == (FT_UInt)size->root.metrics.x_ppem && |
| strike->y_ppm == (FT_UInt)size->root.metrics.y_ppem ) |
| goto Found_Strike; |
| |
| strike++; |
| } |
| |
| /* couldn't find it */ |
| return FT_THROW( Invalid_Argument ); |
| } |
| |
| Found_Strike: |
| |
| /* now look up the glyph's position within the file */ |
| { |
| FT_UInt char_len; |
| |
| |
| char_len = 4; |
| if ( strike->flags & PFR_BITMAP_2BYTE_CHARCODE ) |
| char_len += 1; |
| if ( strike->flags & PFR_BITMAP_2BYTE_SIZE ) |
| char_len += 1; |
| if ( strike->flags & PFR_BITMAP_3BYTE_OFFSET ) |
| char_len += 1; |
| |
| /* access data directly in the frame to speed lookups */ |
| if ( FT_STREAM_SEEK( phys->bct_offset + strike->bct_offset ) || |
| FT_FRAME_ENTER( char_len * strike->num_bitmaps ) ) |
| goto Exit; |
| |
| pfr_lookup_bitmap_data( stream->cursor, |
| stream->limit, |
| strike->num_bitmaps, |
| &strike->flags, |
| character->char_code, |
| &gps_offset, |
| &gps_size ); |
| |
| FT_FRAME_EXIT(); |
| |
| if ( gps_size == 0 ) |
| { |
| /* could not find a bitmap program string for this glyph */ |
| error = FT_THROW( Invalid_Argument ); |
| goto Exit; |
| } |
| } |
| |
| /* get the bitmap metrics */ |
| { |
| FT_Long xpos = 0, ypos = 0, advance = 0; |
| FT_UInt xsize = 0, ysize = 0, format = 0; |
| FT_Byte* p; |
| |
| |
| /* compute linear advance */ |
| advance = character->advance; |
| if ( phys->metrics_resolution != phys->outline_resolution ) |
| advance = FT_MulDiv( advance, |
| (FT_Long)phys->outline_resolution, |
| (FT_Long)phys->metrics_resolution ); |
| |
| glyph->root.linearHoriAdvance = advance; |
| |
| /* compute default advance, i.e., scaled advance; this can be */ |
| /* overridden in the bitmap header of certain glyphs */ |
| advance = FT_MulDiv( (FT_Fixed)size->root.metrics.x_ppem << 8, |
| character->advance, |
| (FT_Long)phys->metrics_resolution ); |
| |
| if ( FT_STREAM_SEEK( face->header.gps_section_offset + gps_offset ) || |
| FT_FRAME_ENTER( gps_size ) ) |
| goto Exit; |
| |
| p = stream->cursor; |
| error = pfr_load_bitmap_metrics( &p, stream->limit, |
| advance, |
| &xpos, &ypos, |
| &xsize, &ysize, |
| &advance, &format ); |
| if ( error ) |
| goto Exit1; |
| |
| /* |
| * Before allocating the target bitmap, we check whether the given |
| * bitmap dimensions are valid, depending on the image format. |
| * |
| * Format 0: We have a stream of pixels (with 8 pixels per byte). |
| * |
| * (xsize * ysize + 7) / 8 <= gps_size |
| * |
| * Format 1: Run-length encoding; the high nibble holds the number of |
| * white bits, the low nibble the number of black bits. In |
| * other words, a single byte can represent at most 15 |
| * pixels. |
| * |
| * xsize * ysize <= 15 * gps_size |
| * |
| * Format 2: Run-length encoding; the high byte holds the number of |
| * white bits, the low byte the number of black bits. In |
| * other words, two bytes can represent at most 255 pixels. |
| * |
| * xsize * ysize <= 255 * (gps_size + 1) / 2 |
| */ |
| switch ( format ) |
| { |
| case 0: |
| if ( ( (FT_ULong)xsize * ysize + 7 ) / 8 > gps_size ) |
| error = FT_THROW( Invalid_Table ); |
| break; |
| case 1: |
| if ( (FT_ULong)xsize * ysize > 15 * gps_size ) |
| error = FT_THROW( Invalid_Table ); |
| break; |
| case 2: |
| if ( (FT_ULong)xsize * ysize > 255 * ( ( gps_size + 1 ) / 2 ) ) |
| error = FT_THROW( Invalid_Table ); |
| break; |
| default: |
| FT_ERROR(( "pfr_slot_load_bitmap: invalid image type\n" )); |
| error = FT_THROW( Invalid_Table ); |
| } |
| |
| if ( error ) |
| { |
| if ( FT_ERR_EQ( error, Invalid_Table ) ) |
| FT_ERROR(( "pfr_slot_load_bitmap: invalid bitmap dimensions\n" )); |
| goto Exit1; |
| } |
| |
| /* |
| * XXX: on 16bit systems we return an error for huge bitmaps |
| * that cause size truncation, because truncated |
| * size properties make bitmap glyphs broken. |
| */ |
| if ( xpos > FT_INT_MAX || |
| xpos < FT_INT_MIN || |
| ysize > FT_INT_MAX || |
| ypos > FT_INT_MAX - (FT_Long)ysize || |
| ypos + (FT_Long)ysize < FT_INT_MIN ) |
| { |
| FT_TRACE1(( "pfr_slot_load_bitmap:" )); |
| FT_TRACE1(( "huge bitmap glyph %ldx%ld over FT_GlyphSlot\n", |
| xpos, ypos )); |
| error = FT_THROW( Invalid_Pixel_Size ); |
| } |
| |
| if ( !error ) |
| { |
| glyph->root.format = FT_GLYPH_FORMAT_BITMAP; |
| |
| /* Set up glyph bitmap and metrics */ |
| |
| /* XXX: needs casts to fit FT_Bitmap.{width|rows|pitch} */ |
| glyph->root.bitmap.width = xsize; |
| glyph->root.bitmap.rows = ysize; |
| glyph->root.bitmap.pitch = (FT_Int)( xsize + 7 ) >> 3; |
| glyph->root.bitmap.pixel_mode = FT_PIXEL_MODE_MONO; |
| |
| /* XXX: needs casts to fit FT_Glyph_Metrics.{width|height} */ |
| glyph->root.metrics.width = (FT_Pos)xsize << 6; |
| glyph->root.metrics.height = (FT_Pos)ysize << 6; |
| glyph->root.metrics.horiBearingX = xpos * 64; |
| glyph->root.metrics.horiBearingY = ypos * 64; |
| glyph->root.metrics.horiAdvance = FT_PIX_ROUND( ( advance >> 2 ) ); |
| glyph->root.metrics.vertBearingX = - glyph->root.metrics.width >> 1; |
| glyph->root.metrics.vertBearingY = 0; |
| glyph->root.metrics.vertAdvance = size->root.metrics.height; |
| |
| /* XXX: needs casts fit FT_GlyphSlotRec.bitmap_{left|top} */ |
| glyph->root.bitmap_left = (FT_Int)xpos; |
| glyph->root.bitmap_top = (FT_Int)( ypos + (FT_Long)ysize ); |
| |
| if ( metrics_only ) |
| goto Exit1; |
| |
| /* Allocate and read bitmap data */ |
| { |
| FT_ULong len = (FT_ULong)glyph->root.bitmap.pitch * ysize; |
| |
| |
| error = ft_glyphslot_alloc_bitmap( &glyph->root, len ); |
| if ( !error ) |
| error = pfr_load_bitmap_bits( |
| p, |
| stream->limit, |
| format, |
| FT_BOOL( face->header.color_flags & |
| PFR_FLAG_INVERT_BITMAP ), |
| &glyph->root.bitmap ); |
| } |
| } |
| |
| Exit1: |
| FT_FRAME_EXIT(); |
| } |
| |
| Exit: |
| return error; |
| } |
| |
| |
| /* END */ |
