CHAPTER 2 PCL - 78
[TrueType scalable font]
<TrueType character descriptor>
Byte
Data
0-1
Format (15)
Continuation (0)
2 - 3
Descriptor size
Class (15)
4 ~
Additional descriptor size
2 + Desc.size
Character Data Size
4 + Desc. size
Glyph ID
6 + Desc. size
TrueType Glyph Data
0-1
Format (15)
Continuation (0)
2 - 3
Descriptor size
Class (15)
4 ~
Additional descriptor size
2 + Desc.size
Character Data Size
4 + Desc. size
Glyph ID
6 + Desc. size
beginning of TrueType Glyph Data
0-1
Format (15)
Continuation (1)
TrueType Glyph Data
Last-2
Reserved Checksum
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The character data follows these header bytes. Characters are represented as raster data and the data bytes are
used to build up an image of the character from left to right and from top to bottom, according to the
character width and height settings.
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Format (UB) - 15 specifies TrueType font.
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Continuation (B) - specifies whether the character data represents a new character (0) or is a continuation of
the character described by the previous character descriptor block (non-zero). If the continuation byte is
non-zero the bytes following it are interpreted as character data.
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Descriptor size (UB) - specifies the character descriptor size in bytes.
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Class (UB) - indicates the character format.
Value Class
1
Bitmap
2
Compressed
Bitmap
3
Contour (Intellifont scalable)
4
Compound Contour (Intellifont scalable)
15
TrueType scalable
ï‚Ÿ
Character data size (UI) - should be the same value as (the character data size + Glyph ID + TrueType Glyph
data) size.
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Glyph ID (UI) - specifies the ID number for glyph data, which is used by the TrueType font scaler.
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TrueType Glyph data - includes the data segment which is associated with the given character as found in
the glyph table of the original TrueType font file.
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Checksum (UB) - should be a value which, when added to "Character data + Glyph ID + TrueType Glyph
data" size, produces a zero result.