Initial implementation of curves

Contributes to #37

lib/squib/api/shapes.rb

@@ -113,5 +113,26 @@ module Squib
       end
     end
 
+    # Draw a curve using the given coordinates
+    #
+    # @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 x1 [Integer] (0) the x-coordinate to place. Supports Unit Conversion, see {file:README.md#Units Units}.
+    # @option opts y1 [Integer] (0) the y-coordinate to place. Supports Unit Conversion, see {file:README.md#Units Units}.
+    # @option opts x2 [Integer] (50) the x-coordinate to place. Supports Unit Conversion, see {file:README.md#Units Units}.
+    # @option opts y2 [Integer] (50) the y-coordinate to place. Supports Unit Conversion, see {file:README.md#Units Units}.
+    # @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}.
+    # @return [nil] intended to be void
+    # @api public
+    def curve(opts = {})
+      opts = needs(opts, [:range, :x1, :y1, :dx1, :dy1, :x2, :y2, :dx2, :dy2,
+                          :layout, :fill_color, :stroke_color, :stroke_width])
+      opts[:range].each do |i|
+        @cards[i].curve(opts[:x1][i], opts[:y1][i], opts[:dx1][i], opts[:dy1][i],
+                        opts[:x2][i], opts[:y2][i], opts[:dx2][i], opts[:dy2][i],
+                        opts[:fill_color][i], opts[:stroke_color][i], opts[:stroke_width][i])
+      end
+    end
+
   end
 end

lib/squib/constants.rb

@@ -12,6 +12,10 @@ module Squib
       :count_format => '%02d',
       :default_font => 'Arial 36',
       :dir => '_output',
+      :dx1 => 0,
+      :dx2 => 0,
+      :dy1 => 0,
+      :dy2 => 0,
       :ellipsize => :end,
       :face => :left,
       :fill_color => '#0000',
@@ -97,6 +101,10 @@ module Squib
           :blend => :blend,
           :circle_radius => :radius,
           :color => :color,
+          :dx1 => :dx1,
+          :dx2 => :dx2,
+          :dy1 => :dy1,
+          :dy2 => :dy2,
           :ellipsize => :ellipsize,
           :files => :file,
           :fill_color => :fill_color,

lib/squib/graphics/cairo_context_wrapper.rb

@@ -22,7 +22,7 @@ module Squib
         :show_pango_layout, :rounded_rectangle, :set_line_width, :stroke, :fill,
         :set_source, :scale, :render_rsvg_handle, :circle, :triangle, :line_to,
         :operator=, :show_page, :clip, :transform, :mask, :create_pango_layout,
-        :antialias=
+        :antialias=, :curve_to
 
       # :nodoc:
       # @api private

lib/squib/graphics/shapes.rb

@@ -58,5 +58,21 @@ module Squib
       end
     end
 
+        # :nodoc:
+    # @api private
+    def curve(x1, y1, dx1, dy1, x2, y2, dx2, dy2, fill_color, stroke_color, stroke_width)
+      use_cairo do |cc|
+        cc.move_to(x1, y1)
+        cc.curve_to(dx1, dy1, dx2, dy2, x2, y2)
+        cc.set_line_width(stroke_width)
+        cc.set_source_squibcolor(stroke_color)
+        cc.stroke
+        cc.move_to(x1, y1)  
+        cc.curve_to(dx1, dy1, dx2, dy2, x2, y2)
+        cc.set_source_squibcolor(fill_color)
+        cc.fill
+      end
+    end
+
   end
 end