working heatmap

src/backends.jl

@@ -711,7 +711,7 @@ const _pgfplotsx_attr = merge_with_base_supported([
 #     :contour, :path3d, :scatter3d, :surface, :wireframe, :volume,
 #     :shape
 # ]
-const _pgfplotsx_seriestype = [:path, :path3d, :scatter, :steppre, :stepmid, :steppost, :histogram2d, :ysticks, :xsticks, :contour, :shape, :straightline,]
+const _pgfplotsx_seriestype = [:path, :path3d, :scatter, :steppre, :heatmap, :stepmid, :steppost, :histogram2d, :ysticks, :xsticks, :contour, :shape, :straightline,]
 const _pgfplotsx_style = [:auto, :solid, :dash, :dot, :dashdot, :dashdotdot]
 const _pgfplotsx_marker = [:none, :auto, :circle, :rect, :diamond, :utriangle, :dtriangle, :ltriangle, :rtriangle, :cross, :xcross, :star5, :pentagon, :hline, :vline, Shape]
 const _pgfplotsx_scale = [:identity, :ln, :log2, :log10]

src/backends/pgfplotsx.jl

@@ -9,6 +9,19 @@ end
 
 pgfx_axes(pgfx_plot::PGFPlotsXPlot) = pgfx_plot.the_plot.elements[1].elements[1].contents
 
+function surface_to_vecs(x::AVec, y::AVec, s::Union{AMat, Surface})
+    a = Array(s)
+    xn = Vector{eltype(x)}(undef, length(a))
+    yn = Vector{eltype(y)}(undef, length(a))
+    zn = Vector{eltype(s)}(undef, length(a))
+    for (n, (i, j)) in enumerate(Tuple.(CartesianIndices(a)))
+        xn[n] = x[j]
+        yn[n] = y[i]
+        zn[n] = a[i,j]
+    end
+    return xn, yn, zn
+end
+
 function Base.show(io::IO, mime::MIME, pgfx_plot::PGFPlotsXPlot)
     show(io::IO, mime, pgfx_plot.the_plot)
 end
@@ -69,16 +82,32 @@ function (pgfx_plot::PGFPlotsXPlot)(plt::Plot{PGFPlotsXBackend})
                     pgfx_axis!(axis_opt, sp, letter)
                 end
             end
-            if hascolorbar(sp)
+            # Search series for any gradient. In case one series uses a gradient set
-                PGFPlotsX.push_preamble!(pgfx_plot.the_plot, """\\pgfplotsset{
+               # the colorbar and colomap.
-                    colormap={plots$(sp.attr[:subplot_index])}{$(pgfx_colormap(series.plotattributes[col]))},
+               # The reasoning behind doing this on the axis level is that pgfplots
-                }""")
+               # colorbar seems to only works on axis level and needs the proper colormap for
-                pushed_colormap = true
+               # correctly displaying it.
-                push!(axis_opt,
+               # It's also possible to assign the colormap to the series itself but
-                    "colorbar" => nothing,
+               # then the colormap needs to be added twice, once for the axis and once for the
-                    "colormap name" => "plots$(sp.attr[:subplot_index])",
+               # series.
-                )
+               # As it is likely that all series within the same axis use the same
-            end
+               # colormap this should not cause any problem.
+               for series in series_list(sp)
+                   for col in (:markercolor, :fillcolor, :linecolor)
+                       if typeof(series.plotattributes[col]) == ColorGradient
+                            PGFPlotsX.push_preamble!(pgfx_plot.the_plot, """\\pgfplotsset{
+                                colormap={plots$(sp.attr[:subplot_index])}{$(pgfx_colormap(series.plotattributes[col]))},
+                            }""")
+                            push!(axis_opt,
+                                "colorbar" => nothing,
+                                "colormap name" => "plots$(sp.attr[:subplot_index])",
+                            )
+                           # goto is needed to break out of col and series for
+                           @goto colorbar_end
+                       end
+                   end
+               end
+               @label colorbar_end
 
             push!(axis_opt, "colorbar style" => PGFPlotsX.Options(
                 "title" => sp[:colorbar_title],
@@ -101,11 +130,13 @@ function (pgfx_plot::PGFPlotsXPlot)(plt::Plot{PGFPlotsXBackend})
                 opt = series.plotattributes
                 st = series[:seriestype]
                 series_opt = PGFPlotsX.Options(
-                                "color" => opt[:linecolor],
+                                "color" => single_color(opt[:linecolor]),
                             )
                 # function args
                 args = if st == :contour
                     opt[:x], opt[:y], opt[:z].surf'
+                elseif st == :heatmap
+                    surface_to_vecs(opt[:x], opt[:y], opt[:z])
                 elseif is3d(st)
                     opt[:x], opt[:y], opt[:z]
                 elseif st == :straightline
@@ -153,8 +184,21 @@ function (pgfx_plot::PGFPlotsXPlot)(plt::Plot{PGFPlotsXBackend})
                         PGFPlotsX.Table(Contour.contours(args..., opt[:levels]))
                     )
                     push!(axis, surface_plot)
-                elseif st == :histogram2d
+                elseif st == :heatmap
-                    hist_
+                    # TODO: global view setting
+                    push!(axis.options,
+                        "view" => "{0}{90}",
+                        "shader" => "flat corner",
+                    )
+                    heatmap_opt = PGFPlotsX.Options(
+                        "surf" => nothing,
+                        "mesh/rows" => length(opt[:x])
+                     )
+                    heatmap_plot = PGFPlotsX.Plot3(
+                        merge(series_opt, heatmap_opt),
+                        PGFPlotsX.Table(args)
+                    )
+                    push!(axis, heatmap_plot)
                 else
                     # treat segments
                     segments = iter_segments(series)
@@ -273,6 +317,11 @@ function pgfx_colormap(grad::ColorGradient)
         @sprintf("rgb=(%.8f,%.8f,%.8f)", red(c), green(c), blue(c))
     end,"\n")
 end
+function pgfx_colormap(grad::Vector{<:Colorant})
+    join(map(grad) do c
+        @sprintf("rgb=(%.8f,%.8f,%.8f)", red(c), green(c), blue(c))
+    end,"\n")
+end
 
 function pgfx_framestyle(style::Symbol)
     if style in _pgfx_framestyles

test/test_pgfplotsx.jl

@@ -74,7 +74,20 @@ end
      end # testset
      @testset "Histogram 2D" begin
         histogram2d(randn(10000), randn(10000), nbins=20)
-        # TODO: totally broken, errors also for pgfplots
+        # TODO: should work, when heatmaps works?
+     end # testset
+     @testset "Heatmap" begin
+        xs = [string("x", i) for i = 1:10]
+        ys = [string("y", i) for i = 1:4]
+        z = float((1:4) * reshape(1:10, 1, :))
+        pgfx_plot = heatmap(xs, ys, z, aspect_ratio=1)
+        Plots._update_plot_object(pgfx_plot)
+        if @test_nowarn(haskey(Plots.pgfx_axes(pgfx_plot.o)[1].options.dict, "colorbar") == true)
+           @test Plots.pgfx_axes(pgfx_plot.o)[1]["colorbar"] === nothing
+           @test Plots.pgfx_axes(pgfx_plot.o)[1]["colormap name"] == "plots1"
+        end
+        # TODO: wrong colors
+        # TODO: lines instead of patches
      end # testset
      @testset "Contours" begin
         x = 1:0.5:20