working on annotations

src/args.jl

@@ -105,6 +105,7 @@ _seriesDefaults[:fillto]      = nothing          # fills in the area
 _seriesDefaults[:reg]         = false               # regression line?
 _seriesDefaults[:group]       = nothing
 _seriesDefaults[:ribbon]      = nothing
+_seriesDefaults[:annotation]  = nothing
 _seriesDefaults[:args]        = []     # additional args to pass to the backend
 _seriesDefaults[:kwargs]      = []   # additional keyword args to pass to the backend
                               # note: can be Vector{Dict} or Vector{Tuple} 
@@ -186,6 +187,10 @@ const _keyAliases = Dict(
     :area         => :fillto,
     :g            => :group,
     :r            => :ribbon,
+    :ann          => :annotation,
+    :anns         => :annotation,
+    :annotate     => :annotation,
+    :annotations  => :annotation,
     :xlab         => :xlabel,
     :ylab         => :ylabel,
     :yrlab        => :yrightlabel,

src/backends/gadfly.jl

@@ -301,6 +301,32 @@ end
 # ----------------------------------------------------------------
 
 
+function createAnnotationObject(x, y, val::AbstractString)
+  Gadfly.Guide.annotation(Compose.compose(
+                              Compose.context(), 
+                              Compose.text(x, y, val)
+                              # Compose.fill(colorant"black"),
+                              # Compose.stroke(colorant"black")
+                            ))
+end
+
+function addAnnotations(plt::Plot{GadflyPackage}, d::Dict)
+  if haskey(d, :annotation)
+    anns = d[:annotation]
+    if !(isa(anns, AbstractVector) && issubtype(eltype(anns), Tuple))
+      error("Expecting a vector of tuples for annotations: (x, y, annotation)\n    got: $(typeof(anns))")
+    end
+
+    for ann in anns
+      x, y, val = ann
+      push!(plt.o.guides, createAnnotationObject(x, y, val))
+    end
+  end
+end
+
+# ----------------------------------------------------------------
+
+
 # create the underlying object (each backend will do this differently)
 function buildSubplotObject!(subplt::Subplot{GadflyPackage})
   subplt.o = nothing

src/plot.jl

@@ -114,6 +114,8 @@ function plot!(plt::Plot, args...; kw...)
 
   end
 
+  addAnnotations(plt, d)
+
   # add title, axis labels, ticks, etc
   updatePlotItems(plt, d)
   currentPlot!(plt)