[deltacloud-devel] [PATCH aggregator 04/10] Added MultiArea layer

[Martyn Taylor]

From: martyntaylor <mtaylor(a)redhat.com&gt;

---
 lib/scruffy/layers.rb            |    3 +-
 lib/scruffy/layers/multi_area.rb |  119 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 121 insertions(+), 1 deletions(-)
 create mode 100644 lib/scruffy/layers/multi_area.rb

diff --git a/lib/scruffy/layers.rb b/lib/scruffy/layers.rb
index 88908a9..732d802 100644
--- a/lib/scruffy/layers.rb
+++ b/lib/scruffy/layers.rb
@@ -15,10 +15,11 @@ end
 
 require 'scruffy/layers/base'
 require 'scruffy/layers/area'
+require 'scruffy/layers/multi_area'
 require 'scruffy/layers/all_smiles'
 require 'scruffy/layers/bar'
 require 'scruffy/layers/line'
 require 'scruffy/layers/average'
 require 'scruffy/layers/stacked'
 require 'scruffy/layers/pie'
-require 'scruffy/layers/pie_slice'
\ No newline at end of file
+require 'scruffy/layers/pie_slice'
diff --git a/lib/scruffy/layers/multi_area.rb b/lib/scruffy/layers/multi_area.rb
new file mode 100644
index 0000000..10f07e5
--- /dev/null
+++ b/lib/scruffy/layers/multi_area.rb
@@ -0,0 +1,119 @@
+module Scruffy::Layers
+  # ==Scruffy::Layers::MulitArea
+  #
+  # Author:: Martyn Taylor
+  # Date:: July 30th 2010
+  #
+  # Multi Area graph.
+
+  class MultiArea < Base
+
+    attr_accessor :baselines
+    attr_accessor :area_colors
+
+    def initialize(options = {}, &block)
+      super(options)
+      @area_colors = options[:area_colors] ? options[:area_colors] : nil
+      @baselines = options[:baselines] ? options[:baselines] : nil
+    end
+
+    # Render Multi Area graph.
+    def draw(svg, coords, options={})
+      # Check whether to use color from theme, or whether to use user defined colors from
the area_colors array
+      color_count = nil
+      if @area_colors && @area_colors.size > 0
+        area_color = @area_colors[0]
+        color_count = 1
+      else
+        puts "Never Set Area Color"
+        area_color = color
+      end
+
+      # Draw Bottom Level Polygons (Original Coords)
+      draw_poly(svg, coords, area_color, options = {})
+
+      # Draw Lower Area Polygons
+      if @baselines
+        # Get the Color of this Area
+        puts "Drawing Baselines"
+        @baselines.sort! {|x,y| y <=> x }
+        @baselines.each do |baseline|
+          if color_count
+            area_color = area_colors[color_count]
+            color_count = color_count + 1
+            puts area_color.to_s
+            if color_count >= area_colors.size
+              color_count = 0
+            end
+          end
+
+          lower_poly_coords = create_lower_polygon_coords(translate_number(baseline),
coords, options)
+          draw_poly(svg, lower_poly_coords, area_color, options = {})
+        end
+      end
+    end
+
+    private
+    def draw_poly(svg, coords, color, options={})
+      points_value1 = "0,#{height} #{stringify_coords(coords).join(' ')}
#{width},#{height}"
+      svg.polygon(:points => points_value1, :fill => color.to_s, :stroke =>
color.to_s, 'style' => "opacity: #{opacity}")
+    end
+
+    def calculate_intersection(baseline, point1, point2)
+      x1 = point1[0]
+      y1 = point1[1]
+      x2 = point2[0]
+      y2 = point2[1]
+
+      # Check whether baseline intersects with the two point line from these coords
+      if ((y2 >= baseline) && (y1 <= baseline)) || ((y1 >= baseline)
&& (y2 <= baseline))
+        # Calculate point of intersection
+        y = baseline.to_f
+        m = (y2.to_f - y1.to_f) / (x2.to_f - x1.to_f)
+        c = y1.to_f
+
+        x = (y.to_f - c.to_f) / m.to_f
+        return [x + x1, y]
+      elsif (y2 <= baseline) && (y1 <= baseline)
+        return nil
+      else
+        return [x2, y2]
+      end
+    end
+
+
+    def create_lower_polygon_coords(baseline, coords, options={})
+      lower_poly_coords = []
+      if coords[0][1] <= baseline
+        lower_poly_coords << [coords[0][0], baseline]
+      else
+        lower_poly_coords << coords[0]
+      end
+
+      coords.each_index do |index|
+        if index + 1 < coords.size
+          poi = calculate_intersection(baseline, coords[index], coords[index + 1])
+          if poi
+            lower_poly_coords << poi
+            if(coords[index + 1][1] > baseline)
+              lower_poly_coords << coords[index + 1]
+            end
+          end
+        end
+      end
+
+      if coords.last[1] <= baseline
+        lower_poly_coords << [coords.last[0], baseline]
+      else
+        lower_poly_coords << coords.last
+      end
+
+      return lower_poly_coords
+    end
+
+    def translate_number(baseline)
+      relative_percent = ((baseline == min_value) ? 0 : ((baseline.to_f - min_value.to_f)
/ (max_value.to_f - min_value.to_f).to_f))
+      return (height.to_f - (height.to_f * relative_percent))
+    end
+  end
+end
\ No newline at end of file
-- 
1.7.1.1