Tex4ht outputs a script file (`.lg') describing how the dvi file (extension `.ivd') of pictures should be
processed. In the default setting, the script file holds abstract commands of the following form.
--- needs --- source.ivd[i] ==> target.gif ---
--- characters ---
Alternatives to `--- needs --- source.ivd[i] ==> target.gif ---'
The default setting is made with a request of the form `--- needs --- %%1.ivd[%%2] ==> %%3.gif ---',
where the parameters %%1, %%2, and %%3 respectively represent the name of the source file without
its extension, a page number, and a name of the target file. Alternative patterns to these abstract
commands can be requested in the following locations, with the order reflecting on the priority given to the
requests.
tex4ht, where the pattern should be prefixed with `-s'.
tex4ht.env' within a block of consecutive lines, where the lines should be identified with
the character `s'.
tex4ht with the pattern provided through the variable LGPIC of `tex4ht.c'.
%' can be introduced into a pattern through the entry `%%%'. On the other hand, the
parameters `%%1', `%%2', and `%%3' can specify, between the first two percentage characters (i.e., `%...%1',
`%...%2', and `%...%3'), any format for the outcome that is compatible with the print formats of
C.
Alternatives to `--- characters ---'
Substitutions for this abstract command can be requested in the following locations.
tex4ht, prefixed with `-b'.
tex4ht.file', where the line should be identified with the character
`b'.
tex4ht with the substitution provided during compilation time through the variable LGSEP of
`tex4ht.c'.