updated gg_raster to use max resolution for all plots by default, add…

…ressing #24

DESCRIPTION

@@ -1,10 +1,10 @@
 Package: basemaps
 Type: Package
 Title: Accessing Spatial Basemaps in R
-Version: 0.0.6
+Version: 0.0.7
 Depends:
   R (>= 3.5.0)
-Date: 2024-03-03
+Date: 2024-04-05
 Authors@R: person("Jakob", "Schwalb-Willmann", email = "[email protected]",
   role = c("aut", "cre"), comment = c(ORCID = "0000-0003-2665-1509"))
 Description: A lightweight package to access spatial basemaps from open sources such as 'OpenStreetMap', 'Carto', 'Mapbox' and others in R.
@@ -31,4 +31,4 @@ Suggests:
   testthat,
   covr
 BugReports: https://github.com/16eagle/basemaps/issues
-RoxygenNote: 7.2.3
+RoxygenNote: 7.3.1

NEWS.md

@@ -1,5 +1,18 @@
 ***
 
+## basemaps 0.0.6
+Minor improvements
+
+**Changes:**
+
+* maps rendered using `basemap_ggplot` or `basemap_gglayer` or objects plotted using `gg_raster` are now displayed with all pixels by default (full resolution, `maxpixels` argument) instead of rendering in a lower resolution (previous default: `500000`).
+* switched from using `aes_string` to `aes` in `gg_raster` due to deprectation of the function in `ggplot2`.
+
+<br>
+
+
+***
+
 ## basemaps 0.0.6
 Major improvements, adding new map services
 

R/basemap.R

@@ -15,6 +15,7 @@
 #'    \item \code{browse}, logical, for \code{class = "png"} and interactive sessions only. Whether to open the png file in the system's default PNG viewer or not. Default is \code{TRUE}.
 #'    \item \code{col}, character vector of colours for transforming single-layer basemaps into RGB, if \code{class = "png"} or \code{class = "magick"}. Default is \code{topo.colors(25)}.
 #'    \item \code{dpi},  numeric vector of length 1 or 2 specifying the resolution of the image in DPI (dots per inch) for x and y (in that order) - it is recycled to length 2.
+#'    \item etc. (see \code{?gg_raster} for valid arguments when using \code{class = "gglayer"} or \code{class = "ggplot"}, including \code{maxpixels} to control resolution of ggplot outputs
 #' }
 #' @param verbose logical, if \code{TRUE}, messages and progress information are displayed on the console (default).
 #' 

R/plot.R

@@ -7,7 +7,7 @@
 #' @param gglayer logical, if \code{FALSE} (default), a \code{ggplot2} plot is returned, if \code{TRUE}, a \code{ggplot2} layer is returned.
 #' @param ... additional arguments, including
 #' \itemize{
-#'    \item \code{maxpixels}, numeric, maximum number of pixels to be plotted (default: 500000)
+#'    \item \code{maxpixels}, numeric, maximum number of pixels to be plotted (default: number of pixels in r). Use a value lower then ncell(r) to lower resolution for faster plotting.
 #'    \item \code{alpha}, numeric between 0 and 1, alpha value of the plotted data (transparency).
 #'    \item \code{maxColorValue}, numeric, the value  to use as colour maximum.
 #'    \item \code{interpolate}, logical, whether to smooth the plot (default is \code{TRUE}).
@@ -34,12 +34,19 @@
 #' @export
 gg_raster <- function(r, r_type = "RGB", gglayer = F, ...){
 
+  if(!any(grepl("ggplot", rownames(installed.packages())))){
+    out(paste0("Package 'ggplot2' is not installed, but needed for class='", class, "'. Please install 'ggplot2' using install.packages('ggplot2')."), type = 3)
+  }
+
   if(inherits(r, "Raster")){
     r <- rast(r)
   }
+  if(!inherits(r, "SpatRaster")){
+    out("Argument r needs to be a raster of class 'SpatRaster', 'RasterLayer', 'RasterBrick' or 'RasterStack'.", type = 3)
+  }
 
   extras <- list(...)
-  if(!is.null(extras$maxpixels)) maxpixels <- extras$maxpixels else maxpixels <- 500000
+  if(!is.null(extras$maxpixels)) maxpixels <- extras$maxpixels else maxpixels <- ncell(r)  #500000
   if(!is.null(extras$alpha)) alpha <- extras$alpha else alpha <- 1
   if(!is.null(extras$maxColorValue)) maxColorValue <- extras$maxColorValue else maxColorValue <- NA
   if(!is.null(extras$interpolate)) interpolate <- extras$interpolate else interpolate <- TRUE
@@ -49,7 +56,7 @@ gg_raster <- function(r, r_type = "RGB", gglayer = F, ...){
   if(maxpixels < ncell(r)) r <- aggregate(r, fact = ceiling(ncell(r)/maxpixels))
 
   # transform into data.frame
-  df <- data.frame(as.data.frame(r, xy = T))
+  df <- data.frame(as.data.frame(r, xy = T, na.rm = F))
   colnames(df) <- c("x", "y", paste0("val", 1:(ncol(df)-2)))
 
   # factor if discrete to show categrocial legend
@@ -77,11 +84,14 @@ gg_raster <- function(r, r_type = "RGB", gglayer = F, ...){
     if(any(na.sel)) df <- df[!na.sel,]
   }
   # if NA gaps are there, use geom_tile, otherwise make it fast using geom_raster
+  .data <- ggplot2::.data
   if(any(na.sel)){
     # remark: is this ever called?
-    gg <- ggplot2::geom_tile(ggplot2::aes_string(x = "x", y = "y", fill = "fill"), data = df, alpha = alpha)
+    out(paste0("Using geom_tile() with maxpixels = ", maxpixels, "."))
+    gg <- ggplot2::geom_tile(ggplot2::aes(x = .data$x, y = .data$y, fill = .data$fill), data = df, alpha = alpha)
   } else{
-    gg <- ggplot2::geom_raster(ggplot2::aes_string(x = "x", y = "y", fill = "fill"), data = df, alpha = alpha, interpolate = interpolate)
+    out(paste0("Using geom_raster() with maxpixels = ", maxpixels, "."))
+    gg <- ggplot2::geom_raster(ggplot2::aes(x = .data$x, y = .data$y, fill = .data$fill), data = df, alpha = alpha, interpolate = interpolate)
   }
 
   if(isFALSE(gglayer)){

tests/testthat/test-plot.R

@@ -5,4 +5,7 @@ test_that("gg_raster()", {
   map <- basemap_raster(ext, map_dir = map_dir, verbose = F)
   expect_is(gg_raster(map, r_type = "RGB"), "gg")
   expect_is(gg_raster(map, r_type = "RGB", gglayer = F), "gg")
+
+  map <- basemap_stars(ext, map_dir = map_dir, verbose = F)
+  expect_error(gg_raster(map, r_type = "RGB", gglayer = F))
 })