Revert "fix linetype scale"

This reverts commit 99a1222.

Author: teunbrand

Diff for: scales-other.qmd

@@ -245,25 +245,26 @@ base <- ggplot(df, aes(linetype = value)) +
 base
 ```
 
-You can control the line type by specifying a string with up to 8 hexadecimal values (i.e., from 0 to F).
-In this specification, the first value is the length of the first line segment, the second value is the length of the first space between segments, and so on.
-This allows you to specify your own line types using `scale_linetype_manual()`:
+You can control the line type by specifying a string with up to 8 hexadecimal values (i.e., from 0 to F). In this specification, the first value is the length of the first line segment, the second value is the length of the first space between segments, and so on. This allows you to specify your own line types using `scale_linetype_manual()`, or alternatively, by passing a custom function to the `palette` argument:
 
 ```{r}
 #| eval: false
-types <- c(
-  "55",
-  "75",
-  "95",
-  "1115",
-  "111115",
-  "11111115",
-  "5158",
-  "9198",
-  "c1c8"
-)
+linetypes <- function(n) {
+  types <- c(
+    "55",
+    "75",
+    "95",
+    "1115",
+    "111115",
+    "11111115",
+    "5158",
+    "9198",
+    "c1c8"
+  )
+  return(types[seq_len(n)])
+}
 
-base + scale_linetype_manual(values = linetypes)
+base + scale_linetype(palette = linetypes)
 ```
 
 Note that the last four lines are blank, because the `linetypes()` function defined above returns `NA` when the number of categories exceeds 9. The `scale_linetype()` function contains a `na.value` argument used to specify what kind of line is plotted for these values. By default this produces a blank line, but you can override this by setting `na.value = "dotted"`: