color2

NEWS.md

@@ -3,6 +3,7 @@ Each release typically has a number of minor bug fixes beyond what is listed her
 
 # Version 1.x
 
+ * Add aesthetic `color2`, a second color scale (#1436)
  * Enable `color` aesthetic for `Stat.qq` (#1434)
  * Add `Geom.bar(position=:identity)` + alpha enabled (#1428)
  * Enable stacked guides (#1423)

docs/src/gallery/guides.md

@@ -36,6 +36,24 @@ hstack(pa, pb)
 ```
 
 
+## [`Guide.color2key`](@ref)
+```@example
+using Gadfly, RDatasets
+set_default_plot_size(14cm, 9cm)
+
+iris = dataset("datasets","iris")
+gp = Geom.polygon(preserve_order=true, fill=true)
+plot(iris,
+    layer(x=:SepalLength, y=:SepalWidth, color2=:Species, alpha=[1.0]),
+    layer(x=:SepalLength, y=:SepalWidth, gp,  order=1,
+        Stat.density2d(levels=[0.05:0.05:0.4;]),
+        Theme(alphas=[0.15], lowlight_color=identity)),
+    Scale.color_continuous,
+    Guide.colorkey,  Guide.color2key(title="Iris"),
+    Theme(point_size=3pt, key_swatch_shape=Shape.circle, alphas=[0.7]))
+```
+
+
 ## [`Guide.manual_color_key`](@ref)
 
 ```@example

docs/src/gallery/scales.md

@@ -132,12 +132,21 @@ hstack(pa,pb)
 ## [`Scale.color_none`](@ref)
 
 ```@example
-using Gadfly
-set_default_plot_size(21cm, 8cm)
-xs = ys = 1:10.
-zs = Float64[x^2*log(y) for x in xs, y in ys]
-p1 = plot(x=xs, y=ys, z=zs, Geom.contour);
-p2 = plot(x=xs, y=ys, z=zs, Geom.contour, Scale.color_none);
+using Gadfly, RDatasets
+set_default_plot_size(21cm, 9cm)
+
+iris = dataset("datasets", "iris")
+p1 = plot(iris, x=:SepalLength, y=:SepalWidth, color2=:Species,
+    layer(Geom.density2d(levels=[0.1:0.1:0.4;]),  order=1),
+    Geom.point, Scale.color_continuous,
+    Guide.colorkey, Guide.color2key(title="Iris"),
+    Theme(point_size=3pt, key_swatch_shape=Shape.circle, line_width=1.5pt)
+)
+p2 = plot(iris, x=:SepalLength, y=:SepalWidth, color2=:Species,
+    layer(Geom.density2d(levels=[0.1:0.1:0.4;]),  order=1),
+    Geom.point, Scale.color_none,  Guide.color2key(title="Iris"),
+    Theme(default_color="gray", point_size=3pt, key_swatch_shape=Shape.circle)
+)
 hstack(p1,p2)
 ```
 

docs/src/tutorial.md

@@ -213,6 +213,7 @@ hstack(p3, p4)
 | `x` | `x_discrete` | `xticks` |  |
 | `y` | `y_discrete` | `yticks` |  |
 | `color` | `color_discrete` | `colorkey` | (tbd) |
+| `color2` | `color2_discrete` | `color2key` | `color2s` |
 | `shape` | `shape_discrete` | `shapekey` | `point_shapes` |
 | `size` | `size_discrete` | --- | `point_size_min`, `point_size_max` |
 |         | `size_discrete2`| `sizekey` |  `discrete_sizemap` |

src/Gadfly.jl

@@ -663,7 +663,7 @@ function render_prepare(plot::Plot)
                                     datas..., subplot_datas...)
 
     # set defaults for key titles
-    keyvars = [:color, :shape, :size]
+    keyvars = [:color, :shape, :size, :color2]
     for (i, layer) in enumerate(plot.layers)
         for kv in keyvars
             fflag = (getfield(layer_aess[i], Symbol(kv,"_key_title")) == nothing) && haskey(layer.mapping, kv) && !isa(layer.mapping[kv], AbstractArray)
@@ -704,7 +704,7 @@ function render_prepare(plot::Plot)
     Stat.apply_statistics(statistics, scales, coord, plot_aes)
 
     # Add some default guides determined by defined aesthetics
-    keytypes = [Guide.ColorKey, Guide.ShapeKey, Guide.SizeKey]
+    keytypes = [Guide.ColorKey, Guide.ShapeKey, Guide.SizeKey, Guide.Color2Key]
     supress_keys = false
     for layer in plot.layers
         if isa(layer.geom, Geom.SubplotGeometry) && any(haskey.((layer.geom.guides,), keytypes))
@@ -1136,6 +1136,7 @@ const default_aes_scales = Dict{Symbol, Dict}(
         :shape  => Scale.shape_identity(),
         :size   => Scale.size_identity(),
         :color  => Scale.color_identity(),
+        :color2 => Scale.color2_identity()
     ),
 
     :numerical => Dict{Symbol, Any}(
@@ -1184,7 +1185,8 @@ const default_aes_scales = Dict{Symbol, Dict}(
         :group      => Scale.group_discrete(),
         :label      => Scale.label(),
         :alpha       => Scale.alpha_discrete(),
-        :linestyle  => Scale.linestyle_discrete()
+        :linestyle  => Scale.linestyle_discrete(),
+        :color2     => Scale.color2_discrete()
     )
 )
 

src/aesthetics.jl

@@ -21,6 +21,7 @@ const NumericalOrCategoricalAesthetic =
     color,        Union{CategoricalAesthetic,Vector,Nothing}
     alpha,        NumericalOrCategoricalAesthetic
     linestyle,    Union{CategoricalAesthetic,Vector,Nothing}
+    color2,       Union{IndirectArray, Vector, Nothing}
 
     label,        CategoricalAesthetic
     group,        CategoricalAesthetic
@@ -66,6 +67,7 @@ const NumericalOrCategoricalAesthetic =
     shape_key_title,      Maybe(AbstractString)
     size_key_title,       Maybe(AbstractString)
     size_key_vals,        Maybe(AbstractDict)
+    color2_key_title,     Maybe(AbstractString)
 
     # mark some ticks as initially invisible
     xtickvisible,         Maybe(Vector{Bool})
@@ -91,6 +93,7 @@ const NumericalOrCategoricalAesthetic =
     ygroup_label, Function, showoff
     shape_label, Function, showoff
     size_label,   Function, showoff
+    color2_label, Function, showoff
 
     # pseudo-aesthetics
     pad_categorical_x, Union{Missing,Bool}, missing

src/data.jl

@@ -36,6 +36,7 @@
     xsize
     ysize
     color
+    color2
     group
     label
     alpha

src/geom/point.jl

@@ -30,7 +30,7 @@ Draw scatter plots of the `x` and `y` aesthetics.
 """
 const point = PointGeometry
 
-element_aesthetics(::PointGeometry) = [:x, :y, :size, :color, :shape, :alpha]
+element_aesthetics(::PointGeometry) = [:x, :y, :size, :color, :shape, :alpha, :color2]
 
 # Generate a form for a point geometry.
 #
@@ -64,10 +64,15 @@ function render(geom::PointGeometry, theme::Gadfly.Theme, aes::Gadfly.Aesthetics
     end
 
     aes_alpha = eltype(aes.alpha) <: Int ? theme.alphas[aes.alpha] : aes.alpha
+    aes_color = if aes.color2 !== nothing
+        eltype(aes.color2) <: Int ? theme.color2s[aes.color2] : aes.color2
+    else 
+        aes.color
+    end
 
     ctx = context()
 
-    for (x, y, color, size, shape, alpha) in Compose.cyclezip(aes.x, aes.y, aes.color, aes_size, aes.shape, aes_alpha)
+    for (x, y, color, size, shape, alpha) in Compose.cyclezip(aes.x, aes.y, aes_color, aes_size, aes.shape, aes_alpha)
         shapefun = typeof(shape) <: Function ? shape : theme.point_shapes[shape]
         strokecolor = aes.color_key_continuous != nothing && aes.color_key_continuous ?
                     theme.continuous_highlight_color(color) :

src/guide/keys.jl

@@ -213,7 +213,7 @@ SizeKey(v::Nothing) = SizeKey(visible=false)
 SizeKey(title::AbstractString, labels::Vector{String}, pos::Vector) = SizeKey(title, labels, pos, true)
 
 """
-    Guide.sizekey[(; title="size", labels=String[], pos=[])]
+    Guide.sizekey[(; title="Size", labels=String[], pos=[])]
     Guide.sizekey(title, labels, pos)
 
 Enable control of the sizekey.  Set the key `title` and the item `labels`.
@@ -260,3 +260,54 @@ function render(guide::SizeKey, theme::Gadfly.Theme, aes::Gadfly.Aesthetics)
 end
 
 
+
+struct Color2Key <: Gadfly.GuideElement
+    title::AbstractString
+    labels::Vector{String}
+    pos::Vector
+    visible::Bool
+end
+Color2Key(;title="Color2", labels=String[], pos=Float64[], visible=true) = Color2Key(title, labels, pos, visible)
+Color2Key(v::Nothing) = Color2Key(visible=false)
+Color2Key(title::AbstractString, labels::Vector{String}, pos::Vector) = Color2Key(title, labels, pos, true)
+
+"""
+    Guide.color2key[(; title="Color2", labels=String[], pos=[])]
+    Guide.color2key(title, labels, pos)
+
+Enable control of the color2key.  Set the key `title` and the item `labels`.
+`pos` overrides [Theme(key_position=)](@ref Gadfly) and can be in either
+relative (e.g. [0.7w, 0.2h] is the lower right quadrant), absolute (e.g. [0mm,
+0mm]), or plot scale (e.g. [0,0]) coordinates. `Guide.color2key(nothing)` will hide the key.
+"""
+const color2key = Color2Key
+
+function render(guide::Color2Key, theme::Gadfly.Theme, aes::Gadfly.Aesthetics)
+
+    (theme.key_position==:none || !guide.visible || (eltype(aes.color2)<:Colorant)) && return PositionedGuide[]
+    gpos = guide.pos
+    (theme.key_position==:inside) && isempty(gpos) &&  (gpos = [0.7w, 0.25h])
+
+    # Aesthetics for keys: color2_key_title, color2_label (Function)
+    ncolors = length(unique(aes.color2))
+    guide_title = (guide.title≠"Color2" || aes.color2_key_title==nothing) ? guide.title : aes.color2_key_title
+    color2_key_labels = isempty(guide.labels) ? aes.color2_label(1:ncolors) : guide.labels
+
+    title_context, title_width = render_key_title2(guide_title, theme)
+    ctxs = render_discrete_key(color2_key_labels, title_context, title_width, theme, colors=theme.color2s[1:ncolors])
+
+    position, stackable = right_guide_position, true
+    if !isempty(gpos)
+        position, stackable = over_guide_position, false
+        ctxs = [compose(context(), (context(gpos[1],gpos[2]), ctxs[1]))]
+    elseif theme.key_position == :left
+        position = left_guide_position
+    elseif theme.key_position == :top
+        position = top_guide_position
+    elseif theme.key_position == :bottom
+        position = bottom_guide_position
+    end
+
+    return [PositionedGuide(ctxs, 0, position, stackable)]
+end
+

src/scale.jl

@@ -364,6 +364,15 @@ alpha_discrete(; labels=nothing, levels=nothing, order=nothing) =
 @doc type_discrete_docstr("linestyle") linestyle_discrete(; labels=nothing, levels=nothing, order=nothing) =
         DiscreteScale([:linestyle], labels=labels, levels=levels, order=order)
 
+"""
+    color2_discrete[(; labels=nothing, levels=nothing, order=nothing)]
+
+Similar to [`Scale.x_discrete`](@ref), except applied to the `color2` aesthetic. The color2 palette
+is set by `Theme(color2s=[])`.
+"""     
+color2_discrete(; labels=nothing, levels=nothing, order=nothing) =
+        DiscreteScale([:color2], labels=labels, levels=levels, order=order)
+
 
 function apply_scale(scale::DiscreteScale, aess::Vector{Gadfly.Aesthetics}, datas::Gadfly.Data...)
 
@@ -751,8 +760,9 @@ element_aesthetics(scale::IdentityScale) = [scale.var]
 function apply_scale(scale::IdentityScale,
                      aess::Vector{Gadfly.Aesthetics}, datas::Gadfly.Data...)
     for (aes, data) in zip(aess, datas)
-        getfield(data, scale.var) === nothing && continue
-        setfield!(aes, scale.var, getfield(data, scale.var))
+        datavar = getfield(data, scale.var)
+        datavar===nothing && continue
+        setfield!(aes, scale.var, datavar)
     end
 end
 
@@ -787,6 +797,10 @@ shape_identity() = IdentityScale(:shape)
 """
 size_identity() = IdentityScale(:size)
 
+"""
+    color2_identity()
+"""
+color2_identity() = IdentityScale(:color2)
 
 include("scale/scales.jl")
 

src/theme.jl

@@ -105,6 +105,9 @@ $(FIELDS)
     "Alpha palette. The default palette is [1.0, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.0]. Customize using a Vector of length one or greater, with 0.0≤values≤1.0",
     alphas,         Vector{Float64}, [1.0, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.0]
 
+    "Discrete colors for `color2`.  The default palette is `Scale.default_discrete_colors(50)`. Customize using a `Vector{<:Color}`.", 
+    color2s,               (Vector{<:Color}),    Scale.default_discrete_colors(50)
+
     "Background color used in the main plot panel. (Color or Nothing)",
     panel_fill,            ColorOrNothing,  nothing
 

test/testscripts/scale_color2.jl

@@ -0,0 +1,29 @@
+using Gadfly, RDatasets
+
+set_default_plot_size(6.6inch, 4inch)
+
+quakes = dataset("datasets", "quakes")
+quakes.Richter = floor.(Int, quakes.Mag) 
+m = Matrix(quakes[:,[2,1]])
+X = [ones(1000) m m.^2]
+B = X'X \ X'quakes.Depth
+fn(x,y) = ([1 x y x^2 y^2]*B)[1]
+
+# p1 is an example of Scale.color2_identity
+p1 = plot(quakes, x=:Depth, y=:Mag,
+    layer(x=:Depth, y=:Mag, color2=[colorant"gray"], alpha=[0.3], size=[2pt]),
+    layer(Geom.density2d(levels=7), order=1), Scale.color_continuous,
+    Theme(key_position=:none)
+)
+
+p2 = plot(quakes,
+    layer(x=:Long, y=:Lat, color2=:Richter, alpha=[0.7]),
+    layer(fn, 165, 190, -40, 0, Stat.contour(levels=[0:250:1500;])),
+    Scale.color_continuous(minvalue=0),
+    Scale.color2_discrete(levels=[4,5,6]), 
+    Guide.colorkey(title="Depth"),
+    Theme(point_size=1.5pt, key_swatch_shape=Shape.circle, 
+        discrete_highlight_color=c->nothing)
+)
+
+hstack(p1, p2)

test/testscripts/shape_hvline.jl

@@ -1,4 +1,6 @@
 using Gadfly
 
+set_default_plot_size(6inch, 3inch)
+
 hstack(plot(y=[1,2,3],shape=[Shape.vline], Theme(discrete_highlight_color=x->x)),
        plot(y=[1,2,3],shape=[Shape.hline], Theme(discrete_highlight_color=x->x)))