import code for area plots

Author: v0dro

lib/rubyplot/axes.rb

@@ -53,21 +53,19 @@ def initialize figure, position
     end
 
     def scatter! *args, &block
-      plot = with_backend "Scatter", *args
-      yield(plot) if block_given?
-      @plots << plot
+      add_plot "Scatter", *args, &block
     end
 
     def bar! *args, &block
-      plot = with_backend "Bar", *args
-      yield(plot) if block_given?
-      @plots << plot
+      add_plot "Bar", *args, &block
     end
 
     def line! *args, &block
-      plot = with_backend "Line", *args
-      yield(plot) if block_given?
-      @plots << plot
+      add_plot "Line", *args, &block
+    end
+
+    def area! *args, &block
+      add_plot "Area", *args, &block
     end
 
     def write file_name
@@ -76,6 +74,12 @@ def write file_name
 
     private
 
+    def add_plot plot_type, *args, &block
+      plot = with_backend plot_type, *args
+      yield(plot) if block_given?
+      @plots << plot
+    end
+
     def with_backend plot_type, *args
       plot =
       case Rubyplot.backend

lib/rubyplot/magick_wrapper/plot.rb

@@ -1,3 +1,4 @@
 require_relative 'plot/scatter'
 require_relative 'plot/bar'
 require_relative 'plot/line'
+require_relative 'plot/area'

lib/rubyplot/magick_wrapper/plot/area.rb

@@ -0,0 +1,53 @@
+require_relative 'area/geometry'
+
+module Rubyplot
+  module MagickWrapper
+    module Plot
+      class Area < Artist
+        def initialize(*)
+          super
+          @sorted_drawing = true
+          @all_colors_array = Magick.colors
+        end
+
+        def draw
+          super
+          return unless @geometry.has_data
+
+          @x_increment = @graph_width / (@geometry.column_count - 1).to_f
+          @d = @d.stroke 'transparent'
+
+          @geometry.norm_data.each_with_index do |data_row, i|
+            poly_points = []
+            prev_x = prev_y = 0.0
+            @d = @d.fill @plot_colors[i]
+
+            data_row[DATA_VALUES_INDEX].each_with_index do |data_point, index|
+              # Use incremented x and scaled y
+              new_x = @graph_left + (@x_increment * index)
+              new_y = @graph_top + (@graph_height - data_point * @graph_height)
+
+              poly_points << new_x
+              poly_points << new_y
+
+              draw_label(new_x, index)
+
+              prev_x = new_x
+              prev_y = new_y
+            end
+
+            # Add closing points, draw polygon
+            poly_points << @graph_right
+            poly_points << @graph_bottom - 1
+            poly_points << @graph_left
+            poly_points << @graph_bottom - 1
+            @d.fill_opacity(0.3)
+            @d = @d.polyline(*poly_points)
+          end
+
+          @d.draw(@base_image)
+        end
+      end
+    end
+  end
+end

lib/rubyplot/magick_wrapper/plot/area/geometry.rb

@@ -0,0 +1,15 @@
+module Rubyplot
+  module MagickWrapper
+    module Plot
+      class Area < MagickWrapper::Artist
+        class Geometry < MagickWrapper::Artist::Geometry
+          attr_accessor :spacing_factor
+          def initialize(*)
+            super
+            @spacing_factor = 0.9
+          end
+        end # class Geometry
+      end # class Area
+    end # module Plot
+  end # module MagickWrapper
+end # module Rubyplot

spec/axes_spec.rb

@@ -12,6 +12,63 @@
         ["Venus", [90, 34, 23, 12, 78, 89, 98, 88]]
       ]
     end
+
+    context "#area!", focus: true do
+      before do 
+        @temp_dir = SPEC_ROOT + "temp/area"
+        @fix_dir = SPEC_ROOT + "fixtures/area"
+        FileUtils.mkdir_p @temp_dir
+      end
+
+      it "plots a single simple Area graph" do
+        fig = Rubyplot::Figure.new
+        axes = fig.add_subplot 0,0
+        axes.area! do |p|
+          p.data [25, 36, 86, 39, 25, 31, 79, 88]
+          p.label = "Jimmy"
+        end
+        axes.title = "Visual simple area graph test."
+        axes.x_ticks = {
+          0 => '0',
+          2 => '2',
+          4 => '4',
+          6 => '6'
+        }
+
+        file = "/#{Rubyplot.backend}_simple_area.png"
+        fig.write(@temp_dir + file)
+
+        #expect("temp/area" + file).to eq_image("fixtures/area" + file)
+      end
+
+      it "plots multiple area plots on the same Axes" do
+        fig = Rubyplot::Figure.new
+        axes = fig.add_subplot 0,0
+        [
+          ["Jimmy", [25, 36, 86, 39, 25, 31, 79, 88]],
+          ["Charles", [80, 54, 67, 54, 68, 70, 90, 95]],
+          ["Julie", [22, 29, 35, 38, 36, 40, 46, 57]],
+          ["Jane", [3, 95, 95, 90, 85, 80, 88, 100]]
+        ].each do |n, data|
+          axes.area! do |p|
+            p.data data
+            p.label = n
+          end
+        end
+        axes.title = "Multiple area plots on same axes."
+        axes.x_ticks = {
+          0 => '0',
+          2 => '2',
+          4 => '4',
+          6 => '6'
+        }
+
+        file = "/#{Rubyplot.backend}_multiple_area.png"
+        fig.write(@temp_dir + file)
+
+        #expect("temp/area" + file).to eq_image("fixtures/area" + file)
+      end
+    end
 
     context "#line!" do
       before do 
@@ -305,7 +362,7 @@
           p.label = "peaches"
         end
         axes.title = "Pos/neg bar graph test."
-        axes.labels = {
+        axes.x_ticks = {
           0 => '5/6',
           1 => '5/15',
           2 => '5/24',
@@ -322,7 +379,7 @@
         fig = Rubyplot::Figure.new
         axes = fig.add_subplot 0,0
         axes.title = "all negative bar graph."
-        axes.labels = {
+        axes.x_ticks = {
           0 => '5/6',
           1 => '5/15',
           2 => '5/24',
@@ -357,7 +414,7 @@
             p.label = name
           end
         end
-        axes.labels = {
+        axes.x_ticks = {
           0 => '5/6',
           1 => '5/15',
           2 => '5/24',
@@ -385,7 +442,7 @@
             p.label = name
           end
         end
-        axes.labels = { 0 => '2003', 2 => '2004', 4 => '2005' }
+        axes.x_ticks = { 0 => '2003', 2 => '2004', 4 => '2005' }
 
         file = "/#{Rubyplot.backend}_adjust_legens.png"
         fig.write(@temp_dir + file)