feat: 'reset_image_cache()'

* `reset_image_cache()` resets the image cache used by `grid.pattern_image()`
   and `grid.pattern_placeholder()` to store images (#63).

closes #25, closes #63

DESCRIPTION

@@ -1,9 +1,9 @@
 Package: gridpattern
 Type: Package
 Title: 'grid' Pattern Grobs
-Version: 1.0.4
+Version: 1.1.0
 Authors@R: c(person("Mike", "FC", role = "aut", comment = "Code/docs adapted from ggpattern"),
-        person("Trevor L.", "Davis", role=c("aut", "cre"), email="[email protected]",
+        person("Trevor L", "Davis", role=c("aut", "cre"), email="[email protected]",
                comment = c(ORCID = "0000-0001-6341-4639")),
         person("Thomas Lin", "Pedersen", role = "ctb", comment = "new_data_frame() copied from ggplot2"))
 Description: Provides 'grid' grobs that fill in a user-defined area with various patterns.  Includes enhanced versions of the geometric and image-based patterns originally contained in the 'ggpattern' package as well as original 'pch', 'polygon_tiling', 'regular_polygon', 'rose', 'text', 'wave', and 'weave' patterns plus support for custom user-defined patterns.
@@ -27,7 +27,7 @@ Imports:
 Suggests:
     ambient,
     knitr,
-    magick,
+    magick (>= 2.7.4),
     ragg (>= 1.2.0),
     rmarkdown,
     svglite (>= 2.1.0),

NAMESPACE

@@ -40,6 +40,7 @@ export(patternGrob)
 export(pattern_hex)
 export(pattern_square)
 export(pattern_weave)
+export(reset_image_cache)
 export(star_angle)
 export(star_scale)
 import(grid)

NEWS.md

@@ -1,8 +1,14 @@
-gridpattern v1.0.4
+gridpattern v1.1.0
 ==================
 
-Minor improvements
-------------------
+New Features
+------------
+
+* `reset_image_cache()` resets the image cache used by `grid.pattern_image()` 
+   and `grid.pattern_placeholder()` to store images (#63).
+
+Bug fixes and minor improvements
+--------------------------------
 
 * The function `guess_has_R4.1_features()` is now available as a "standalone" file.
   You may copy its source under the permissive [MIT No Attribution (MIT-0)](https://spdx.org/licenses/MIT-0.html) 

R/pattern-array-image.R

@@ -21,7 +21,8 @@
 #' @param filter Filter to use when scaling. `magick::filter_types()` returns a vector of supported values.
 #' @return A grid grob object invisibly.  If `draw` is `TRUE` then also draws to the graphic device as a side effect.
 #' @examples
-#'   if (require("magick")) {
+#'   \donttest{# May emit a "CPU time > 2.5 times elapsed time" NOTE in a CRAN check
+#'   if (requireNamespace("magick")) {
 #'     x_hex <- 0.5 + 0.5 * cos(seq(2 * pi / 4, by = 2 * pi / 6, length.out = 6))
 #'     y_hex <- 0.5 + 0.5 * sin(seq(2 * pi / 4, by = 2 * pi / 6, length.out = 6))
 #'     logo_filename <- system.file("img", "Rlogo.png" , package = "png")
@@ -33,8 +34,11 @@
 #'     try(grid.pattern_image(x_hex, y_hex, filename = logo_filename,
 #'                            type = "tile"))
 #'   }
+#'   }
 #' @seealso [grid.pattern_placeholder()] is an image pattern that uses images
 #'          downloaded from the internet.
+#'          [reset_image_cache()] resets the image cache used by `grid.pattern_image()`
+#'          and [grid.pattern_placeholder()].
 #' @export
 grid.pattern_image <- function(x = c(0, 0, 1, 1), y = c(1, 0, 0, 1), id = 1L, ...,
                                filename = "", type = "fit", scale = 1,

R/pattern-array-magick.R

@@ -12,7 +12,7 @@
 #' @param fill Fill colour
 #' @return A grid grob object invisibly.  If `draw` is `TRUE` then also draws to the graphic device as a side effect.
 #' @examples
-#'   if (require("magick")) {
+#'   if (requireNamespace("magick")) {
 #'     x_hex <- 0.5 + 0.5 * cos(seq(2 * pi / 4, by = 2 * pi / 6, length.out = 6))
 #'     y_hex <- 0.5 + 0.5 * sin(seq(2 * pi / 4, by = 2 * pi / 6, length.out = 6))
 #'     grid.pattern_magick(x_hex, y_hex, type="octagons", fill="blue", scale=2)

R/pattern-array-placeholder.R

@@ -8,14 +8,15 @@
 #'             If you would like only greyscale images append `bw` to the name.
 #' @return A grid grob object invisibly.  If `draw` is `TRUE` then also draws to the graphic device as a side effect.
 #' @examples
-#'   if (require("magick")) {
+#'   if (requireNamespace("magick")) {
 #'     x_hex <- 0.5 + 0.5 * cos(seq(2 * pi / 4, by = 2 * pi / 6, length.out = 6))
 #'     y_hex <- 0.5 + 0.5 * sin(seq(2 * pi / 4, by = 2 * pi / 6, length.out = 6))
 #'     # requires internet connection to download from placeholder image websites
 #'     try(grid.pattern_placeholder(x_hex, y_hex, type="bear"))
 #'   }
 #'
 #'   print(names_placeholder)
+#' @seealso [reset_image_cache()] resets the image cache used by [grid.pattern_image()] and `grid.pattern_placeholder()`.
 #' @export
 grid.pattern_placeholder <- function(x = c(0, 0, 1, 1), y = c(1, 0, 0, 1), id = 1L, ...,
                                      type = "kitten", alpha = gp$alpha %||% NA_real_,

R/pattern-array-plasma.R

@@ -6,12 +6,13 @@
 #' @param scale Extra scaling
 #' @return A grid grob object invisibly.  If `draw` is `TRUE` then also draws to the graphic device as a side effect.
 #' @examples
-#'   if (require("magick")) {
+#'   if (requireNamespace("magick")) {
 #'     x_hex <- 0.5 + 0.5 * cos(seq(2 * pi / 4, by = 2 * pi / 6, length.out = 6))
 #'     y_hex <- 0.5 + 0.5 * sin(seq(2 * pi / 4, by = 2 * pi / 6, length.out = 6))
 #'     grid.pattern_plasma(x_hex, y_hex, fill = "green")
 #'   }
 #' @seealso [grid.pattern_ambient()] provides a noise pattern using the `ambient` package.
+#'          Pseudorandom seeds for the plasma pattern may be set via [magick::magick_set_seed()].
 #' @export
 grid.pattern_plasma <- function(x = c(0, 0, 1, 1), y = c(1, 0, 0, 1), id = 1L, ...,
                                 fill = gp$fill %||% "grey80", scale = 1, alpha = gp$alpha %||% NA_real_,

R/reset_image_cache.R

@@ -0,0 +1,9 @@
+#' Reset 'gridpattern' image cache
+#'
+#' [grid.pattern_image()] and [grid.pattern_placeholder()] store images in a cache
+#' (so we won't download image URLs over and over).
+#' `reset_image_cache()` resets this cache.
+#' @export
+reset_image_cache <- function() {
+    memoise::forget(img_read_memoised)
+}

cran-comments.md

@@ -1,3 +1,6 @@
+* Example that triggered a "Examples with CPU time > 2.5 times elapsed time" NOTE
+  is now wrapped in `\donttest{}`.
+
 ## Test environments
 
 * local (linux, R 4.3.1)

tests/testthat/test_array.R

@@ -35,7 +35,7 @@ test_that("array patterns works as expected", {
     skip_on_ci()
     skip_on_cran()
     skip_if_not(capabilities("cairo"))
-    skip_if_not_installed("magick")
+    skip_if_not_installed("magick", "2.7.4")
     skip_if_not_installed("ragg")
 
     x <- 0.5 + 0.5 * cos(seq(2 * pi / 4, by = 2 * pi / 6, length.out = 6))
@@ -71,6 +71,12 @@ test_that("array patterns works as expected", {
                 function() grid.pattern_plasma(x = c(0.5, 0.5, 0.5, 0.5),
                                                y = c(0, 1, 1, 0), fill = "green"))
 
+    test_raster("plasma.png",
+                function() {
+                    magick::magick_set_seed(42) # introduced in v2.7.4
+                    grid.pattern_plasma(x, y, fill = "green")
+                })
+
     playing_card_symbols <- c("\u2660", "\u2665", "\u2666", "\u2663")
     test_raster("text.png",
                 function() grid.pattern_text(x, y, shape = playing_card_symbols,
@@ -85,12 +91,6 @@ test_that("array patterns works as expected", {
                                           use_R4.1_masks = NULL,
                                           frequency = 1:4, gp = gp))
 
-    # plasma images are random and doesn't seem to be a way to set a seed
-    tmpfile <- tempfile(fileext = ".png")
-    grob <- my_png(tmpfile, function() grid.pattern_plasma(fill="green"))
-    unlink(tmpfile)
-    expect_true(inherits(grob, "pattern"))
-
     create_pattern_simple <- function(width, height, params, legend) {
       choice <- params$pattern_type
       if (is.null(choice) || is.na(choice) || !is.character(choice)) {