Panel plots with categorical rasters

[jflowernet]

When plotting multi-layer categorical rasters, it would be nice to be able to plot them with a single, common legend. panel() does not seem to accept categorical rasters so it appears there is no way to do this at the moment? Any chance this option could be implemented in the future?

library(terra)
#> terra 1.7.29

r <- rast(nrows=5, ncols=9)
values(r) <- sample(3, ncell(r), replace = TRUE)
x <- c(r, r, r)

levels_df <- data.frame(id=1:3, type = c("river", "land", "ocean"))

levels(x) <- list(levels_df, levels_df, levels_df)

plot(x)

panel(x)
#> Error: [panel] cannot use categorical rasters

^{Created on 2023-05-04 with reprex v2.0.2}

[rhijmans]

That is a bit more tricky because the levels need to match, or at least not conflict, but this now works for your example.

[jflowernet]

Excellent! Many thanks