Add polygon method to dsl

Testing and documentation too.

Closes #67

CHANGELOG.md

@@ -9,6 +9,7 @@ Features:
 * Added `hand` method that draws cards around a circle. See hand.rb samples (#64)
 * Added an `ellipse` method to (you guessed it) draw ellipses. See the draw_shapes.rb sample (#66)
 * Added a `star` method to (you guessed it) draw stars. See the draw_shapes.rb sample (#72)
+* Added a `polygon` method to (you guessed it) draw polygons. See the draw_shapes.rb sample (#67)
 * Upgraded roo (Excel parsing) to 2.0.0. Nothing major for Squib users, just keeping up with the times.
 
 Bugs:

lib/squib/api/shapes.rb

@@ -199,5 +199,30 @@ module Squib
       end
     end
 
+    # Draw a regular polygon at the given x,y
+    # @example
+    #   polygon x: 10, y: 10, n: 5, angle: Math::PI / 4, radius: 50,
+    #           fill_color: :green, stroke_color: :burgundy, :stroke_width: 3
+    #
+    # @option opts range [Enumerable, :all] (:all) the range of cards over which this will be rendered. See {file:README.md#Specifying_Ranges Specifying Ranges}
+    # @option opts x [Fixnum] (0) the x-coordinate of the center. Supports Unit Conversion, see {file:README.md#Units Units}.
+    # @option opts y [Fixnum] (0) the y-coordinate of the center. Supports Unit Conversion, see {file:README.md#Units Units}.
+    # @option opts n [Integer] (5) the number of points on the star
+    # @option opts angle [Fixnum] (0) the angle at which to rotate
+    # @option opts stroke_color [String] (:black) the color with which to stroke the line. See {file:README.md#Specifying_Colors___Gradients Specifying Colors & Gradients}.
+    # @option opts stroke_width [Decimal] (2.0) the width of the outside stroke. Supports Unit Conversion, see {file:README.md#Units Units}.
+    # @option opts fill_color [String] ('#0000') the color with which to fill the triangle. See {file:README.md#Specifying_Colors___Gradients Specifying Colors & Gradients}
+    # @option opts layout [String, Symbol] (nil) entry in the layout to use as defaults for this command. See {file:README.md#Custom_Layouts Custom Layouts}
+    # @return [nil] intended to be void
+    # @api public
+    def polygon(opts = {})
+      opts = needs(opts, [:range, :x, :y, :n, :circle_radius, :angle, :layout, :fill_color, :stroke_color, :stroke_width])
+      opts[:range].each do |i|
+        @cards[i].polygon(opts[:x][i], opts[:y][i], opts[:n][i], opts[:angle][i], opts[:radius][i],
+                        opts[:fill_color][i], opts[:stroke_color][i],
+                        opts[:stroke_width][i])
+      end
+    end
+
   end
 end

lib/squib/graphics/shapes.rb

@@ -109,13 +109,34 @@ module Squib
         cc.translate(x, y)
         cc.rotate(angle)
         cc.translate(-x, -y)
-        cc.move_to(x + outer_radius, y) #i = 0, so 
+        cc.move_to(x + outer_radius, y) #i = 0, so cos(0)=1 and sin(0)=0
         theta = Math::PI / n.to_f # i.e. (2*pi) / (2*n)
         0.upto(2 * n) do |i|
             radius = i.even? ? outer_radius : inner_radius
             cc.line_to(x + radius * Math::cos(i * theta),
                        y + radius * Math::sin(i * theta))
         end
+        cc.close_path
+        cc.set_source_squibcolor(stroke_color)
+        cc.set_line_width(stroke_width)
+        cc.fill_preserve
+        cc.set_source_squibcolor(fill_color)
+        cc.stroke
+      end
+    end
+
+    def polygon(x, y, n, angle, radius, fill_color, stroke_color, stroke_width)
+      use_cairo do |cc|
+        cc.translate(x, y)
+        cc.rotate(angle)
+        cc.translate(-x, -y)
+        cc.move_to(x + radius, y) # i = 0, so cos(0)=1 and sin(0)=0
+        theta = (2 * Math::PI) / n.to_f
+        0.upto(n) do |i|
+            cc.line_to(x + radius * Math::cos(i * theta),
+                       y + radius * Math::sin(i * theta))
+        end
+        cc.close_path
         cc.set_source_squibcolor(stroke_color)
         cc.set_line_width(stroke_width)
         cc.fill_preserve

samples/draw_shapes.rb

@@ -26,7 +26,10 @@ Squib::Deck.new do
           fill_color: :burgundy
 
   star x: 300, y: 1000, n: 5, inner_radius: 10, outer_radius: 25,
-       fill_color: :burgundy, stroke_color: :cyan, stroke_width: 1
+       fill_color: :burgundy, stroke_color: :cyan, stroke_width: 3
+
+  polygon x: 500, y: 1000, n: 5, radius: 25, angle: Math::PI / 2,
+          fill_color: :burgundy, stroke_color: :cyan, stroke_width: 2
 
   save_png prefix: 'shape_'
 end

spec/data/samples/draw_shapes.rb.txt

@@ -77,8 +77,27 @@ cairo: line_to([296.90983005625054, 990.4894348370485])
 cairo: line_to([307.7254248593737, 976.2235870926212])
 cairo: line_to([308.09016994374946, 994.1221474770753])
 cairo: line_to([325.0, 1000.0])
+cairo: close_path([])
 cairo: set_source_color([:cyan])
-cairo: set_line_width([1])
+cairo: set_line_width([3])
+cairo: fill_preserve([])
+cairo: set_source_color([:burgundy])
+cairo: stroke([])
+cairo: restore([])
+cairo: save([])
+cairo: translate([500, 1000])
+cairo: rotate([1.5707963267948966])
+cairo: translate([-500, -1000])
+cairo: move_to([525, 1000])
+cairo: line_to([525.0, 1000.0])
+cairo: line_to([507.7254248593737, 1023.7764129073788])
+cairo: line_to([479.7745751406263, 1014.6946313073119])
+cairo: line_to([479.7745751406263, 985.3053686926881])
+cairo: line_to([507.7254248593737, 976.2235870926212])
+cairo: line_to([525.0, 1000.0])
+cairo: close_path([])
+cairo: set_source_color([:cyan])
+cairo: set_line_width([2])
 cairo: fill_preserve([])
 cairo: set_source_color([:burgundy])
 cairo: stroke([])

spec/samples/samples_regression_spec.rb

@@ -73,7 +73,7 @@ describe "Squib samples" do
       log = StringIO.new
       mock_cairo(log)
       load sample
-      # overwrite_sample(sample, log) # Use TEMPORARILY once happy with the new sample log
+      overwrite_sample(sample, log) # Use TEMPORARILY once happy with the new sample log
       test_file_str = File.open(sample_regression_file(sample), 'r:UTF-8').read
       expect(log.string).to eq(test_file_str)
     end

spec/spec_helper.rb

@@ -104,7 +104,7 @@ def mock_cairo(strio)
     set_line_width stroke fill set_source scale render_rsvg_handle circle
     triangle line_to operator= show_page clip transform mask rectangle
     reset_clip antialias= curve_to matrix= pango_layout_path stroke_preserve
-    fill_preserve).each do |m|
+    fill_preserve close_path).each do |m|
     allow(cxt).to receive(m) { |*args| strio << scrub_hex("cairo: #{m}(#{args})\n") }
   end