Don't import sf and stars fully

[olivroy]

Possibly that prior to v4 release, could remove

#' @import sf
#' @import stars

tmap would potentially load faster?

I think it is fine to leave them for dev as it may be faster to iterate?

[mtennekes]

Good point! For those using terra they are not strictly necessary, so we don't have to import them. What takes sf some time to load is probably the dependencies (geos/proj/gdal).

Internally, the vector-based shapes are internally stored as a list of simple features, and raster-based shapes as an empty stars object (data itself is in a data.table). The preprocessing is class-dependent: terra objects are preprocessed using native terra functions, sf using sf functions, etc.

Perhaps we could use sfheaders in the first place, and only if necessary load sf. Not sure if there is a stars 'headers' package. Alternatively, we could also switch to terra as the main package if that would be lighter weight/faster, but that would take a bit of time to change (a few days).

What are your ideas/opinions?

[olivroy]

Interesting! I was actually thinking of something simpler:

I think that avoiding

#' @import sf
#' @import stars

seemed to decrease load time. (not done, since it could harm development workflow) but what I propose is

Using

#' @importFrom sf st_geometry sf_sf st_as_sf

and namespacing calls with sf:: could help. I did this in #893

[mtennekes]

Done importFrom. Not sure if the loading time is less...

[olivroy]

Oh, it seems that you are right. I must have dreamt something yesterday! Feel free to revert if you find it a burden