Fix #3539 Make sure tiles that runs outside the scale limits are removed (#3547)

Author: thomasp85

NEWS.md

@@ -1,5 +1,8 @@
 # ggplot2 (development version)
 
+* Fix a bug in `geom_raster()` that squeezed the image when it went outside 
+  scale limits (#3539, @thomasp85)
+
 * The evaluation time of aesthetics can now be controlled to a finer degree. 
   `after_stat()` superseeds the use of `stat()` and `..var..`-notation, ad is
   joined by `after_scale()` to allow for mapping to scaled aesthetic values. 

R/geom-raster.r

@@ -45,7 +45,7 @@ geom_raster <- function(mapping = NULL, data = NULL,
 #' @export
 GeomRaster <- ggproto("GeomRaster", Geom,
   default_aes = aes(fill = "grey20", alpha = NA),
-  non_missing_aes = "fill",
+  non_missing_aes = c("fill", "xmin", "xmax", "ymin", "ymax"),
   required_aes = c("x", "y"),
 
   setup_data = function(data, params) {