pyplot colorbar fixes (#2722)

* pyplot colorbar fixes

* pyplot colorbar fixes

* pyplot: sligtly reworked colorbars

* pyplot 3d color bar fixes

* pyplot 3d color bar fixes

src/args.jl

@@ -583,6 +583,7 @@ add_aliases(:fill_z, :fillz, :fz, :surfacecolor, :surfacecolour, :sc, :surfcolor
 add_aliases(:legend, :leg, :key)
 add_aliases(:legendtitle, :legend_title, :labeltitle, :label_title, :leg_title, :key_title)
 add_aliases(:colorbar, :cb, :cbar, :colorkey)
+add_aliases(:colorbar_title, :colorbartitle, :cb_title, :cbtitle, :cbartitle, :cbar_title, :colorkeytitle, :colorkey_title)
 add_aliases(:clims, :clim, :cbarlims, :cbar_lims, :climits, :color_limits)
 add_aliases(:smooth, :regression, :reg)
 add_aliases(:levels, :nlevels, :nlev, :levs)

src/backends/pyplot.jl

@@ -13,6 +13,7 @@ append!(Base.Multimedia.displays, otherdisplays)
 pycolors = PyPlot.pyimport("matplotlib.colors")
 pypath = PyPlot.pyimport("matplotlib.path")
 mplot3d = PyPlot.pyimport("mpl_toolkits.mplot3d")
+axes_grid1 = PyPlot.pyimport("mpl_toolkits.axes_grid1")
 pypatches = PyPlot.pyimport("matplotlib.patches")
 pyfont = PyPlot.pyimport("matplotlib.font_manager")
 pyticker = PyPlot.pyimport("matplotlib.ticker")
@@ -1003,12 +1004,27 @@ function _before_layout_calcs(plt::Plot{PyPlotBackend})
             end
             kw[:spacing] = "proportional"
 
-            # create and store the colorbar object (handle) and the axis that it is drawn on.
-            # note: the colorbar axis is positioned independently from the subplot axis
             fig = plt.o
-            cbax = fig."add_axes"([0.8,0.1,0.03,0.8], label = string(gensym()))
+
+            if RecipesPipeline.is3d(sp)
+                cbax = fig."add_axes"([0.9, 0.1, 0.03, 0.8])
                 cb = fig."colorbar"(handle; cax=cbax, kw...)
+            else
+                # divider approach works only with 2d plots
+                divider = axes_grid1.make_axes_locatable(ax)
+                # width = axes_grid1.axes_size.AxesY(ax, aspect=1.0 / 3.5)
+                # pad = axes_grid1.axes_size.Fraction(0.5, width)  # Colorbar is spaced 0.5 of its size away from the ax
+                # cbax = divider.append_axes("right", size=width, pad=pad)   # This approach does not work well in subplots
+                cbax = divider.append_axes("right", size="5%", pad="2.5%")  # Reasonable value works most of the usecases
+                cb = fig."colorbar"(handle; cax=cbax, kw...)
+            end
+
             cb."set_label"(sp[:colorbar_title],size=py_thickness_scale(plt, sp[:yaxis][:guidefontsize]),family=sp[:yaxis][:guidefontfamily], color = py_color(sp[:yaxis][:guidefontcolor]))
+
+            # cb."formatter".set_useOffset(false)   # This for some reason does not work, must be a pyplot bug, instead this is a workaround:
+            cb."formatter".set_powerlimits((-Inf, Inf))
+            cb."update_ticks"()
+
             for lab in cb."ax"."yaxis"."get_ticklabels"()
                   lab."set_fontsize"(py_thickness_scale(plt, sp[:yaxis][:tickfontsize]))
                   lab."set_family"(sp[:yaxis][:tickfontfamily])
@@ -1220,7 +1236,7 @@ function _update_min_padding!(sp::Subplot{PyPlotBackend})
     # optionally add the width of colorbar labels and colorbar to rightpad
     if haskey(sp.attr, :cbar_ax)
         bb = py_bbox(sp.attr[:cbar_handle]."ax"."get_yticklabels"())
-        sp.attr[:cbar_width] = _cbar_width + width(bb) + 2.3mm + (sp[:colorbar_title] == "" ? 0px : 30px)
+        sp.attr[:cbar_width] = _cbar_width + width(bb) + (sp[:colorbar_title] == "" ? 0px : 30px)
         rightpad = rightpad + sp.attr[:cbar_width]
     end
 
@@ -1381,13 +1397,10 @@ function _update_plot_object(plt::Plot{PyPlotBackend})
         pcts = bbox_to_pcts(sp.plotarea, figw, figh)
         ax."set_position"(pcts)
 
-        # set the cbar position if there is one
-        if haskey(sp.attr, :cbar_ax)
+        if haskey(sp.attr, :cbar_ax) && RecipesPipeline.is3d(sp)   # 2D plots are completely handled by axis dividers
             cbw = sp.attr[:cbar_width]
             # this is the bounding box of just the colors of the colorbar (not labels)
-            ex = sp[:zaxis][:extrema]
-            has_toplabel = !(1e-7 < max(abs(ex.emax), abs(ex.emin)) < 1e7)
-            cb_bbox = BoundingBox(right(sp.bbox)-cbw+1mm, top(sp.bbox) +  (has_toplabel ? 4mm : 2mm), _cbar_width-1mm, height(sp.bbox) - (has_toplabel ? 6mm : 4mm))
+            cb_bbox = BoundingBox(right(sp.bbox)-cbw - 2mm, top(sp.bbox) + 2mm, _cbar_width-1mm, height(sp.bbox) -  4mm)
             pcts = bbox_to_pcts(cb_bbox, figw, figh)
             sp.attr[:cbar_ax]."set_position"(pcts)
         end

src/utils.jl

@@ -988,7 +988,7 @@ px2inch(px::Real)       = float(px / PX_PER_INCH)
 inch2mm(inches::Real)   = float(inches * MM_PER_INCH)
 mm2inch(mm::Real)       = float(mm / MM_PER_INCH)
 px2mm(px::Real)         = float(px * MM_PER_PX)
-mm2px(mm::Real)         = float(px / MM_PER_PX)
+mm2px(mm::Real)         = float(mm / MM_PER_PX)
 
 
 "Smallest x in plot"