enhanced 'dev.capabilities()' support

[trevorld]

Currently {ragg} does not provide full information to the enhanced dev.capabilities() feature introduced in R 4.2:

• https://developer.r-project.org/Blog/public/2021/12/14/updating-graphics-devices-for-r-4.2.0/
• https://cran.r-project.org/doc/manuals/r-devel/R-ints.html#Device-capabilities

ragg::agg_png(tempfile())
print(dev.capabilities())
dev.off()

$semiTransparency
[1] TRUE

$transparentBackground
[1] "fully"

$rasterImage
[1] NA

$capture
[1] FALSE

$locator
[1] FALSE

$events
character(0)

$patterns
[1] NA

$clippingPaths
[1] NA

$masks
[1] NA

$compositing
[1] FALSE

$transformations
[1] FALSE

$paths
[1] FALSE

Note unlike {svglite} this lack of support doesn't currently cause me any headaches since

device <- names(grDevices::dev.cur())
(device %in% c("agg_jpeg", "agg_ppm", "agg_png", "agg_tiff")) && 
        (packageVersion("ragg") >= '1.2.0')

should reliably tell me what I want to know but if every graphics device that added support for masking, gradients, etc. also supported the enhanced dev.capabilities() support it would be much easier for developers to properly guess whether the active graphic device has such support instead of using hacks like the above.

[thomasp85]

Thanks for raising this - I was sure it was deduced automatically

[thomasp85]

it appears the capabilities callback was added in the latest update. Will add this once I get around to add the latest features

[teunbrand]

Thanks Thomas for fixing this ^_^