Virtual fonts

Virtual fonts provide a convenient and flexible way to specify a mapping from TEX's notion of a font character to the capabilities of a particular output device (e.g., screen or printer). In particular, virtual fonts make it easy to use PostScript fonts with TEX. The definitive document on virtual fonts is Donald Knuth's article in TUGboat vol. 11 no. 1. A text version called knuth-vf can be found in the TeX-docs folder. supports virtual fonts via two items in the TEX menu: ``Fix VFs in DVI'' can be used to select a DVI file and replace all virtual font characters with appropriate characters from actual fonts (or with the specified rules and other DVI commands allowed in VF files). The code used to perform this task is based on Peter Breitenlohner's DVIcopy program. Another item, ``Fix VFs after TEX'', can be ticked to tell to automatically fix any VFs in the DVI file created at the end of a TEX run. This means you don't have to remember to run ``Fix VFs in DVI'' before viewing or printing a DVI file that contains virtual fonts. If you intend to make frequent use of virtual fonts then it would be a good idea to tick ``Fix VFs after TEX''. Even if you only use virtual fonts rarely, it doesn't hurt to tick this option. can quickly check to see if any virtual fonts are used in a DVI file; if none are used then no further processing is carried out. To decide if font foo is virtual or not, looks for a file called foo.vf in the VF-files folder. If one or more virtual fonts are used then reads the entire DVI file, creates a new DVI file with no virtual font references, deletes the original DVI file and renames the new file with the original name. If an error is detected, or if you decide to cancel processing, will delete the new file and leave the original file untouched.