Re: search for better regtest comparison algorithm

[Werner LEMBERG]

> I would like to bring up the question if it is really necessary that
> we do all testing "end-to-end", i.e. from input ly code to
> pixel-based graphical output.

It's definitely necessary to do that, since we regularly had rendering
issues with Ghostscript.  However, ...

> IIUC, we have an intermediate graphical language, consisting of the
> various stencil commands, that is mostly backend-agnostic. (modulo
> such things like `\image` or `\postscript`)

... a dedicated 'output debugging backend' that produces nice logging
output would certainly be very beneficial.  The usual question: Who is
going to write such a thing, together with all the necessary
infrastructure stuff and, as you correctly state, the many additional
tests?  And most importantly, is this person willing to maintain it
for at least some time until the backend is stable, mature, and well
documented?


    Werner