TrueType fonts

Cross platform issues

As stated earlier, the fact that TrueType fonts exist on both the Macintosh and PC platform does not guarantee that they are treated equally on both platforms.

A TrueType font can be rendered differently by a different version of an operating system or even screen resolution. For example, the same exact TrueType fonts on a Windows 95A version may flow differently than on a Windows 95C version. A TrueType font on a machine with a 640×480 display may flow differently than 1024×768 (try this is Windows 95 with very small point sizes (4pt) and you will see type reflow).

Different versions of the Mac OS also render TrueType fonts differently. The size and spacing may only vary slightly from version to version (or resolution), but it may be enough to cause type reflow or incorrect spacing.

This tends to make TrueType fonts not very portable since the originator and receiver must have the exact same platform, OS version and monitor resolution to get the same results with the same font.

Outputting TrueType fonts

TrueType fonts cannot simply be sent to any PostScript device. Both the revision (level) of PostScript in the output device and the printer driver that is used to print the font play an important role.

PostScript level 1 devices and some early PostScript level 2 devices cannot properly handle TrueType fonts. PostScript drivers often offer 2 solutions to this problem:

  1. They can convert TrueType fonts to bitmaps. This conversion can be different from one driver to another and very small point sizes may be too thick.
  2. The PostScript driver can use a substitution table and try to replace the TrueType fonts by a more or less equivalent PostScript font that is available on the output device. This means that the output will be different from the intent of the designer.

PostScript 3 RIPs as well as most PostScript Level 2 RIPs shipped in the last four to five years include native TrueType support, in the form of so-called “Type 42” font format support. Type 42 fonts are the TrueType font file sections “wrapped” with the necessary PostScript dictionaries to properly work in PostScript. Every PostScript driver provided by Adobe and Apple for Macintosh since 1991, every Adobe AdobePS PostScript driver version for Windows since 1992, and the equivalent Microsoft PostScript driver for Windows 2000 has provided full “native” TrueType support for PostScript via Type 42. Adobe Acrobat also contains a TrueType rasterizer, making it compatible with TrueType fonts.