POC bin breaks derived from scale breaks

Author: arcresu

R/scale-.R

@@ -657,6 +657,9 @@ ScaleContinuous <- ggproto("ScaleContinuous", Scale,
   minor_breaks = waiver(),
   n.breaks = NULL,
   trans = transform_identity(),
+  freeze_breaks = FALSE,
+  frozen_breaks = NULL,
+  frozen_minor_breaks = NULL,
 
   is_discrete = function() FALSE,
 
@@ -749,10 +752,14 @@ ScaleContinuous <- ggproto("ScaleContinuous", Scale,
       )
     }
 
+    breaks_are_frozen <- !is.null(self$frozen_breaks)
+
     # Compute `zero_range()` in transformed space in case `limits` in data space
     # don't support conversion to numeric (#5304)
     if (zero_range(as.numeric(transformation$transform(limits)))) {
       breaks <- limits[1]
+    } else if (self$freeze_breaks && breaks_are_frozen) {
+      breaks <- self$frozen_breaks
     } else if (is.waive(self$breaks)) {
       if (!is.null(self$n.breaks) && trans_support_nbreaks(transformation)) {
         breaks <- transformation$breaks(limits, self$n.breaks)
@@ -771,6 +778,10 @@ ScaleContinuous <- ggproto("ScaleContinuous", Scale,
       breaks <- self$breaks
     }
 
+    if (self$freeze_breaks && !breaks_are_frozen) {
+      self$frozen_breaks <- breaks
+    }
+
     # Breaks in data space need to be converted back to transformed space
     transformation$transform(breaks)
   },
@@ -794,8 +805,12 @@ ScaleContinuous <- ggproto("ScaleContinuous", Scale,
     # some transforms assume finite major breaks
     b <- b[is.finite(b)]
 
+    breaks_are_frozen <- !is.null(self$frozen_minor_breaks)
+
     transformation <- self$get_transformation()
-    if (is.waive(self$minor_breaks)) {
+    if (self$freeze_breaks && breaks_are_frozen) {
+      breaks <- self$frozen_minor_breaks
+    } else if (is.waive(self$minor_breaks)) {
       if (is.null(b)) {
         breaks <- NULL
       } else {
@@ -819,6 +834,10 @@ ScaleContinuous <- ggproto("ScaleContinuous", Scale,
       breaks <- transformation$transform(self$minor_breaks)
     }
 
+    if (self$freeze_breaks && !breaks_are_frozen) {
+      self$frozen_minor_breaks <- breaks
+    }
+
     # Any minor breaks outside the dimensions need to be thrown away
     discard(breaks, limits)
   },
@@ -875,6 +894,8 @@ ScaleContinuous <- ggproto("ScaleContinuous", Scale,
   clone = function(self) {
     new <- ggproto(NULL, self)
     new$range <- ContinuousRange$new()
+    new$frozen_breaks <- NULL
+    new$frozen_minor_breaks <- NULL
     new
   },
 

R/stat-bin.R

@@ -59,6 +59,7 @@ stat_bin <- function(mapping = NULL, data = NULL,
                      closed = c("right", "left"),
                      pad = FALSE,
                      na.rm = FALSE,
+                     follow.scale = FALSE,
                      keep.zeroes = "all",
                      orientation = NA,
                      show.legend = NA,
@@ -81,6 +82,7 @@ stat_bin <- function(mapping = NULL, data = NULL,
       closed = closed,
       pad = pad,
       na.rm = na.rm,
+      follow.scale = follow.scale,
       orientation = orientation,
       keep.zeroes = keep.zeroes,
       ...
@@ -150,11 +152,15 @@ StatBin <- ggproto("StatBin", Stat,
                            center = NULL, boundary = NULL,
                            closed = c("right", "left"), pad = FALSE,
                            breaks = NULL, flipped_aes = FALSE, keep.zeroes = "all",
+                           follow.scale = FALSE,
                            # The following arguments are not used, but must
                            # be listed so parameters are computed correctly
                            origin = NULL, right = NULL, drop = NULL) {
     x <- flipped_names(flipped_aes)$x
-    if (!is.null(breaks)) {
+    if (follow.scale) {
+      breaks <- scales[[x]]$get_breaks()
+      bins <- bin_breaks(breaks, closed)
+    } else if (!is.null(breaks)) {
       if (is.function(breaks)) {
         breaks <- breaks(data[[x]])
       }