Add scale_alpha_continuous

Author: hadley

NEWS

@@ -29,9 +29,10 @@ ggplot2 0.8.5 (2009-XX-XX) ----------------------------------------
   instead of the previous behaviour where scales where added as layers were
   added - this could cause problems if you layer modified the plot.
   (Implements #28)
-* scale_shape_discrete, scale_size_continuous and scale_linetype_discrete 
-  added to scales to match naming convention of all other scales (Fixes #47)
+* scale_shape_discrete, scale_size_continuous, scale_alpha and
+  scale_linetype_discrete added to scales to match naming convention of all
+  other scales (Fixes #47)
 * scale_colour_gradient, scale_colour_gradient2 & scale_colour_gradientn now
   have formatter argument to match scale_continuous
 * legends will only merge if both the title and all labels are the same.
-  (Fixes #16)
+  (Fixes #16)

R/scale-continuous-alpha.r

@@ -1,6 +1,7 @@
-ScaleAlpha <- proto(ScaleContinuous, expr={
+ScaleAlphaContinuous <- proto(ScaleContinuous, expr={
   doc <- TRUE
   common <- NULL
+  alias <- "scale_alpha"
 
   new <- function(., name=NULL, limits=NULL, breaks=NULL, labels=NULL, trans = NULL, to = c(0.1, 1), legend = TRUE) {
     .super$new(., name=name, limits=limits, breaks=breaks, labels=labels, trans=trans, variable = "alpha", to = to, legend = legend)
@@ -11,7 +12,7 @@ ScaleAlpha <- proto(ScaleContinuous, expr={
   }
   output_breaks <- function(.) .$map(.$input_breaks())
 
-  objname <- "alpha"
+  objname <- "alpha_continuous"
   desc <- "Alpha scale for continuous variable"
 
   icon <- function(.) {

R/xxx.r

@@ -45,6 +45,7 @@ position_identity <- PositionIdentity$build_accessor()
 position_jitter <- PositionJitter$build_accessor()
 position_stack <- PositionStack$build_accessor()
 scale_alpha <- ScaleAlpha$build_accessor()
+scale_alpha_continuous <- ScaleAlphaContinuous$build_accessor()
 scale_area <- ScaleArea$build_accessor()
 scale_colour <- ScaleColour$build_accessor()
 scale_colour_brewer <- ScaleBrewer$build_accessor(list(variable = "\"colour\""))