append layout attribute to layer data

Author: teunbrand

R/layer.R

@@ -98,7 +98,7 @@ layer <- function(geom = NULL, stat = NULL,
                   data = NULL, mapping = NULL,
                   position = NULL, params = list(),
                   inherit.aes = TRUE, check.aes = TRUE, check.param = TRUE,
-                  show.legend = NA, key_glyph = NULL, layer_class = Layer) {
+                  show.legend = NA, key_glyph = NULL, layout = NULL, layer_class = Layer) {
   call_env <- caller_env()
   user_env <- caller_env(2)
 
@@ -132,7 +132,7 @@ layer <- function(geom = NULL, stat = NULL,
   geom_params <- params[intersect(names(params), geom$parameters(TRUE))]
   stat_params <- params[intersect(names(params), stat$parameters(TRUE))]
 
-  ignore <- c("key_glyph", "name")
+  ignore <- c("key_glyph", "name", "layout")
   all <- c(geom$parameters(TRUE), stat$parameters(TRUE), geom$aesthetics(), position$aesthetics(), ignore)
 
   # Take care of plain patterns provided as aesthetic
@@ -192,7 +192,8 @@ layer <- function(geom = NULL, stat = NULL,
     position = position,
     inherit.aes = inherit.aes,
     show.legend = show.legend,
-    name = params$name
+    name = params$name,
+    layout = layout %||% params$layout
   )
 }
 
@@ -280,6 +281,7 @@ Layer <- ggproto("Layer", NULL,
     } else {
       self$computed_mapping <- self$mapping
     }
+    attr(data, "layout") <- self$layout
 
     data
   },