tds: Valid font bitmaps

 
 3.2.2 Valid font bitmaps
 ------------------------
 
 The TWG recognizes that the use of short filenames has many
 disadvantages.  The most vexing is that it results in the creation of
 dozens of different files with the same name.  At a typical site,
 `cmr10.pk' will be the filename for Computer Modern Roman 10pt at 5-10
 magnifications for 2-3 modes. (Section ⇒Duplicate filenames
 discusses duplicate filenames in general.)
 
    To minimize this problem, we strongly recommend that PK files
 contain enough information to identify precisely how they were created:
 at least the mode, base resolution, and magnification used to create the
 font.
 
    This information is easy to supply: a simple addition to the local
 modes used for building the fonts with Metafont will automatically
 provide the required information.  If you have been using a local modes
 file derived from (or that is simply) `modes.mf' (see Appendix ⇒
 Related references), the required information is already in your PK
 files.  If not, a simple addition based on the code found in `modes.mf'
 can be made to your local modes file and the PK files rebuilt.