Error with the classic world map example

[jguelat]

I'm trying to reproduce the classic world map example and found 2 issues. I'm using the following code (from the vignette):

data("World", "land", "rivers", package = "tmap")

m2 <- tm_shape(land) +
  tm_raster("elevation", breaks = c(-Inf, 250, 500, 1000, 1500, 2000, 2500, 3000, 4000, Inf),  
            palette = terrain.colors(9), title = "Elevation (m)") +
  tm_shape(rivers) + 
  tm_lines("lightblue", lwd = "strokelwd", scale = 1.5, legend.lwd.show = FALSE) +
  tm_shape(World, is.master = TRUE) +
  tm_borders("grey20", lwd = .5) +
  tm_grid(projection = "longlat", labels.size = 0.4, lwd = 0.25) +
  tm_text("name", size = "AREA") +
  tm_compass(position = c(0.08, 0.45), color.light = "grey90", size = 3) +
  tm_credits("Eckert IV projection", position = c("RIGHT", "BOTTOM")) +
  tm_style("classic",
         bg.color = "lightblue",
         space.color = "grey90",
         inner.margins = c(0.04, 0.04, 0.03, 0.02), 
         earth.boundary = TRUE) +
  tm_legend(position = c("left", "bottom"), 
            frame = TRUE,
            bg.color = "lightblue")

tmap_save(m2, "classic.png", width = 6.125, scale = .7, dpi = 300, outer.margins = 0)

First I'm getting the following error when trying to save the map:

Error in st_crs.character(grid.projection) : invalid crs: longlat

I managed to save the map after removing the line with "tm_grid", however the elevation layer is then cropped (see attached png).

> sessionInfo()
R version 4.0.3 (2020-10-10)
Platform: x86_64-apple-darwin17.0 (64-bit)
Running under: macOS Mojave 10.14.6

Matrix products: default
BLAS:   /Library/Frameworks/R.framework/Versions/4.0/Resources/lib/libRblas.dylib
LAPACK: /Library/Frameworks/R.framework/Versions/4.0/Resources/lib/libRlapack.dylib

locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] tmap_3.2

loaded via a namespace (and not attached):
 [1] Rcpp_1.0.5         compiler_4.0.3     pillar_1.4.6       RColorBrewer_1.1-2 base64enc_0.1-3    class_7.3-17       tools_4.0.3       
 [8] digest_0.6.27      lattice_0.20-41    viridisLite_0.3.0  lifecycle_0.2.0    tibble_3.0.4       png_0.1-7          pkgconfig_2.0.3   
[15] rlang_0.4.8        DBI_1.1.0          crosstalk_1.1.0.1  parallel_4.0.3     e1071_1.7-4        raster_3.3-13      dplyr_1.0.2       
[22] generics_0.1.0     vctrs_0.3.4        htmlwidgets_1.5.2  classInt_0.4-3     leaflet_2.0.3      grid_4.0.3         tidyselect_1.1.0  
[29] glue_1.4.2         sf_0.9-6           R6_2.5.0           XML_3.99-0.5       sp_1.4-4           purrr_0.3.4        magrittr_1.5      
[36] codetools_0.2-16   stars_0.4-3        tmaptools_3.1      leafsync_0.1.0     htmltools_0.5.0    ellipsis_0.3.1     units_0.6-7       
[43] abind_1.4-5        dichromat_2.0-0    KernSmooth_2.23-17 leafem_0.1.3       lwgeom_0.2-5       crayon_1.3.4      

[Nowosad]

Thanks for opening the issue @jguelat. You can fix the grid issue by using tm_graticules() instead. However, the second issue is still here:

library(tmap)
data("World", "land", "rivers", package = "tmap")

m2 <- tm_shape(land) +
  tm_raster("elevation", breaks = c(-Inf, 250, 500, 1000, 1500, 2000, 2500, 3000, 4000, Inf),  
            palette = terrain.colors(9), title = "Elevation (m)") +
  tm_shape(rivers) + 
  tm_lines("lightblue", lwd = "strokelwd", scale = 1.5, legend.lwd.show = FALSE) +
  tm_shape(World, is.master = TRUE) +
  tm_borders("grey20", lwd = .5) +
  tm_graticules(labels.size = 0.4, lwd = 0.25) +
  tm_text("name", size = "AREA") +
  tm_compass(position = c(0.08, 0.45), color.light = "grey90", size = 3) +
  tm_credits("Eckert IV projection", position = c("RIGHT", "BOTTOM")) +
  tm_style("classic",
           bg.color = "lightblue",
           space.color = "grey90",
           inner.margins = c(0.04, 0.04, 0.03, 0.02), 
           earth.boundary = TRUE) +
  tm_legend(position = c("left", "bottom"), 
            frame = TRUE,
            bg.color = "lightblue")

m2

^{Created on 2020-11-18 by the reprex package (v0.3.0)}

[Nowosad]

@jguelat temporary solution is to use raster.warp = FALSE (see the code below).

library(tmap)
data("World", "land", "rivers", package = "tmap")

m2 <- tm_shape(land, raster.warp = FALSE) +
  tm_raster("elevation", breaks = c(-Inf, 250, 500, 1000, 1500, 2000, 2500, 3000, 4000, Inf),  
            palette = terrain.colors(9), title = "Elevation (m)") +
  tm_shape(rivers) + 
  tm_lines("lightblue", lwd = "strokelwd", scale = 1.5, legend.lwd.show = FALSE) +
  tm_shape(World, is.master = TRUE) +
  tm_borders("grey20", lwd = .5) +
  tm_graticules(labels.size = 0.4, lwd = 0.25) +
  tm_text("name", size = "AREA") +
  tm_compass(position = c(0.08, 0.45), color.light = "grey90", size = 3) +
  tm_credits("Eckert IV projection", position = c("RIGHT", "BOTTOM")) +
  tm_style("classic",
           bg.color = "lightblue",
           space.color = "grey90",
           inner.margins = c(0.04, 0.04, 0.03, 0.02), 
           earth.boundary = TRUE) +
  tm_legend(position = c("left", "bottom"), 
            frame = TRUE,
            bg.color = "lightblue")

m2

^{Created on 2020-11-18 by the reprex package (v0.3.0)}

[jguelat]

Thanks for having a look at it! Your solution seems to work but the plotting is slower when using raster.warp = FALSE

The fix with tm_graticules (instead of tm_grid) works well as long as I plot the map by calling m2. Instead, if I try to save the map using the code from the vignette: tmap_save(m2, "classic.png", width = 6.125, scale = .7, dpi = 300, outer.margins = 0) then I'm getting the following error:

Error in eval(substitute(expr), e) : 
  When grid labels are plotted outside the frame, outer.margins (the bottom and the left) should be greater than 0. When using tmap_save, notice that outer.margins are set to 0 by default, unless set to NA.

The error is gone if I slightly adjust the outer.margins (like outer.margins = 0.01)

[mtennekes]

The raster issue: apparently, stars::st_warp crops the raster:

land_eck = stars::st_warp(land, crs = st_crs(World))
plot(land_eck)

The outer.margins error: the error message contains the answer. When you plot grid lines or graticules, the labels are printed in the outer margins area, so they need to be strictly positive.

[mtennekes]

@edzer do you have any idea?

[edzer]

Looks like collateral damage from r-spatial/mapview#256

[edzer]

Should work now!

[jguelat]

Thanks a lot !!!