On 16/09/2015 01:51, Bruno Le Floch wrote: > On 9/15/15, Joseph Wright <[log in to unmask]> wrote: >> On 15/09/2015 09:12, Alexander Grahn wrote: >>> Good morning, >>> >>> There is a number of functions in the new l3sys package for testing the >>> current engine, but I am still missing a public interface for testing >>> the driver. The l3drivers package internally uses some mechanism to >>> distinguish between pdfmode, dvips, dvipdfmx and xdvipdfmx. Will there be >>> such a testing be included in the public interface of expl3 one day? >>> >>> Currently, I am still using a combination if the `ifpdf' package and the >>> \*_if_engine* functions for the purpose of driver detection. >>> >>> Kind regards, >>> Alexander >> >> Hello Alexander, >> >> Adding material to l3sys is on the 'to do' list but there are several >> things there for 'soon'! I can certainly look to add a DVI/PDF test >> (definitely one to do). >> >> In terms of drivers, we could/should move that code to l3sys anyway. The >> question of to what extent any code of this form should be outside of >> the kernel is tricky: for say drawing I can imagine something akin to >> pgf's system layer with a low-level public interface on top (there are a >> limited number of well-defined operations). For what you want (I'm >> guessing) that's not so clear: I've not looked in detail but I assume >> the entire set up for movie inclusion is highly system-dependent. >> >> Joseph > > I think it makes sense indeed to provide a conditional for the driver > in use. However, we should provide wrappers for most operations > (drawing, graphics inclusion, color handling) and explicitly advise > people to use these wrappers rather than the driver conditional. > Movie inclusion is a bit special and may be beyond what we want to > provide wrappers for. But maybe it could make sense to include a > trimmed-down version of media9 as a team-supported package? > > Bruno Quite: I can see how to abstract graphics inclusion, basic drawing operations, etc. but probably not the complexities of movie inclusion! Joseph