CHAPTER 5
418
Text
5.5.2 TrueType Fonts
The
TrueType
font format was developed by Apple Computer, Inc., and has been
adopted as a standard font format for the Microsoft Windows operating system.
Specifications for the TrueType font file format are available in Apple’s
TrueType
Reference Manual
and Microsoft’s
TrueType 1.0 Font Files Technical Specification.
Note:
A TrueType font program can be embedded directly in a PDF file as a stream
object. The Type 42 font format that is defined for PostScript does not apply to PDF.
A TrueType font dictionary can contain the same entries as a Type 1 font dictio-
nary (Table 5.8 on page 413), with the following differences:
•
The value of
Subtype
is
TrueType
.
•
The value of
BaseFont
is derived differently, as described below.
•
The value of
Encoding
is subject to limitations that are described in Section
The PostScript name for the value of
BaseFont
is determined in one of two ways:
•
Use the PostScript name that is an optional entry in the “name” table of the
TrueType font.
•
In the absence of such an entry in the “name” table, derive a PostScript name
from the name by which the font is known in the host operating system. On a
Windows system, the name is based on the
lfFaceName
field in a
LOGFONT
structure; in the Mac OS, it is based on the name of the
FOND
resource. If the
name contains any spaces, the spaces are removed.
If the font in a source document uses a bold or italic style but there is no font data
for that style, the host operating system synthesizes the style. In this case, a com-
ma and the style name (one of
Bold
,
Italic
, or
BoldItalic
) are appended to the font
name. For example, for a TrueType font that is a bold variant of the New York
font, the
BaseFont
value is written as
/NewYork , Bold
(as illustrated in Example