\fromafm always regenerates mtx file

[Lars Hellström]

>Hi,
>
>the \fromafm command seems to always regenerate an mtx file; it seems
>that it would be better if \fromafm checked whether mtx file already
>exists, and only generate it if it does not exist.

I disagree in this case. By saying \fromafm you explicitly specify that you
want to get the metrics from the AFM. Had you wanted to take them from the
MTX, you would have said \frommtx. One reason for keeping the distinction
is that the AFM to MTX conversion is configurable (you can set the minimum
kern size and in v1.9 you can set how the italic correction is computed);
by just picking up a previously generated MTX file, you would have no
chance of knowing with which parameters it was generated. You might also
want to compare with the \frompl commands (the old \frompl has gotten three
new relatives, in case you hadn't noticed)---how would fontinst know in
advance which one of these generated a specific MTX?

Still, fontinst does quite a lot of the kind of optimization you request,
but the decisions are taken at a higher level than that of \fromafm.

Lars Hellström