fixing add.scale.bar()

[ape.git] / R / scales.R

diff --git a/R/scales.R b/R/scales.R
index c8da7e79ec54692c272fcd7a1851ca5293cf1bb6..01f23f5fe96c8e263baf0f319284353de9b5b2ce 100644 (file)
--- a/R/scales.R
+++ b/R/scales.R
@@ -1,24 +1,53 @@
-## scales.R (2008-02-28)
+## scales.R (2009-07-23)
 
 ##   Add a Scale Bar or Axis to a Phylogeny Plot
 
 ## add.scale.bar: add a scale bar to a phylogeny plot
 ## axisPhylo: add a scale axis on the side of a phylogeny plot
 
-## Copyright 2002-2008 Emmanuel Paradis
+## Copyright 2002-2009 Emmanuel Paradis
 
 ## This file is part of the R-package `ape'.
 ## See the file ../COPYING for licensing issues.
 
-add.scale.bar <- function(x = 0, y = 1, length = NULL, ...)
+add.scale.bar <- function(x, y, length = NULL, ...)
 {
     lastPP <- get("last_plot.phylo", envir = .PlotPhyloEnv)
     if (is.null(length)) {
-        nb.digit <- ceiling(log10(mean(lastPP$xx))) - 2
+        nb.digit <-
+          if (lastPP$direction %in% c("rightwards", "leftwards")) diff(range(lastPP$xx))
+          else diff(range(lastPP$yy))
+        nb.digit <- ceiling(log10(nb.digit)) - 2
         length <- eval(parse(text = paste("1e", nb.digit, sep = "")))
     }
-    segments(x, y, x + length, y)
-    text(x + length * 1.1, y, as.character(length), adj = c(0, 0.5), ...)
+    if (missing(x) || missing(y)) {
+        switch(lastPP$direction,
+               "rightwards" = {
+                   x <- 0
+                   y <- 1
+                   segments(x, y, x + length, y)
+                   text(x + length * 1.1, y, as.character(length), adj = c(0, 0.5), ...)
+               },
+               "leftwards" = {
+                   x <- max(lastPP$xx)
+                   y <- 1
+                   segments(x - length, y, x, y)
+                   text(x - length * 1.1, y, as.character(length), adj = c(1, 0.5), ...)
+               },
+               "upwards" = {
+                   x <- max(lastPP$xx)
+                   y <- 0
+                   segments(x, y, x, y + length)
+                   text(x, y + length * 1.1, as.character(length), adj = c(0, 0.5), srt = 90, ...)
+               },
+               "downwards" = {
+                   x <- 1
+                   y <- max(lastPP$yy)
+                   segments(x, y - length, x, y)
+                   text(x, y - length * 1.1, as.character(length), adj = c(0, 0.5), srt = 270, ...)
+               }
+         )
+    }
 }
 
 axisPhylo <- function(side = 1, ...)