fixes handling of colour and fill aesthetics for categorical values

src/draw.jl

@@ -68,6 +68,9 @@ function Makie.SpecApi.Axis(plot::GGPlot)
                 plottable_data = geom.column_transformations[aes][2](aes, source_cols, plot_data)
             elseif eltype(plot_data[!, aes_dict[a]]) <: Union{AbstractString, AbstractChar}
                 plottable_data = cat_inseq(aes, [aes_dict[a]], plot_data)
+                if aes in [:color, :fill]
+                    plottable_data[aes] = as_color(plottable_data[aes])
+                end
             else
                 plottable_data = as_is(aes, [aes_dict[a]], plot_data)
             end

src/transforms.jl

@@ -115,6 +115,30 @@ function kernel_density_2d(target::Symbol, source::Vector{Symbol}, data::DataFra
     return return_dict
 end
 
+# returns nothing, removing aes from graph
+
 function discard(target::Symbol, source::Vector{Symbol}, data::DataFrame)
     return Dict{Symbol, PlottableData}()
-end
+end
+
+# tweaks
+# takes an existing PlottableData object and modifies the makie_function
+
+function as_color(plottable_data_object::PlottableData)
+    colors = [
+               RGB(0/255, 114/255, 178/255), # blue
+               RGB(230/255, 159/255, 0/255), # orange
+               RGB(0/255, 158/255, 115/255), # green
+               RGB(204/255, 121/255, 167/255), # reddish purple
+               RGB(86/255, 180/255, 233/255), # sky blue
+               RGB(213/255, 94/255, 0/255), # vermillion
+               RGB(240/255, 228/255, 66/255), # yellow
+    ]
+
+    return PlottableData(
+        plottable_data_object.raw,
+        (x -> colors[x]) ∘ plottable_data_object.makie_function,
+        plottable_data_object.label_target,
+        plottable_data_object.label_function
+    )
+end