update with method for Spatrasters

[spono]

Adapted the code to work with SpatRaster from the terra package and added the possibility to output the lines as an sf object. There's a horrible workaround to solve a transposition of the data along the second axis (upper right to lower left) but couldn't find a better alternative. Overall, it works smoothly and fast even with high resolution aerial images (tested on 1km tiles with 0.15 cm pixels). If I'll have time, I might work on some other tools

[jwijffels]

Thanks for the changes, I think this requires adding R package terra and R package sf in the Suggests in the DESCRIPTION file as well as some examples in the @examples section, conditional on the availability of terra and sf.

[spono]

ok, great: if the changes I proposed are good for you, I'll push also the other updates as soon as possible. I might have some issues with the material for the example, but let's see

[spono]

Hi, I added an example (the same one from image.contour.detector) due to some constraints with the images I was using.

I realised that all pull requests pushed to my master ended up to this commit: be patiant, I'm not that much used to github and versioning :) BTW, you'll find updates to image.contour.detector too, mostly related to the passage to sf/terra. It happens that running the function line by line it works but, installing the package (through remotes), the SpatRaster method is not found: I guess is related to an update of the NAMESPACE from your (?) side.

[jwijffels]

Thanks, looks already nice, if you could rewrite the code such that we don't have dplyr as Suggest dependency and rename the argument to as_sf instead of export export_sf

[spono]

by now, I only renamed the parameter but I don't have time in these days to find/test an alternative in plain R to group_by & summarize which works smoothly with sf objects

[jwijffels]

If summarize is just a union. Wouldn't this just be using sf::st_union

[spono]

st_union didn't seem to be appropriate due to an issue: I solved using st_combine and removing the usage of dplyr. Nevertheless, attention is needed on one point: even if the method has been added, it is not recognised when the function is called, returning the error no applicable method for 'image_contour_detector' applied to an object of class "SpatRaster". It seems related to the fact that the NAMESPACE is not updated with the new method. I don't know how to solve it but I found this.

[jwijffels]

It seems related to the fact that the NAMESPACE is not updated with the new method. I don't know how to solve it but I found this.

In order to add your functions to the NAMESPACE file, you can run Document in RStudio and also don't forget to run R CMD check. As I see the examples failed.

Can you further document your output structures + have a minimally reproducible example for image_contour_detector.RasterLayer

[spono]

few more small updates.

the example for rasterlayer is the same as terra, but with raster instead of rast.

I added small updates to the output description but, now tht the package supports spatial data, I think it may be important to documene "better" some parameters. For example, I would add something like ; expressed in pixels at the end of the descriptions for union_max_distance and union_min_length (just to avoid confusion).