storing screen resolution, calculating aspect ratio [concerto#131 sta…

…te:open assigned:'Zach Rowe'] [concerto#111 state:open assigned:'Zach Rowe']

app/models/screen.rb

@@ -14,5 +14,26 @@ class Screen < ActiveRecord::Base
   #For now, the check will be string based, it should probably be moved to
   #something like if owner_type.is_class (however that would work)
   validates :owner, :presence => true, :associated => true, :if => Proc.new { ["User", "Group"].include?(owner_type) }
+  validates :width, :presence => true
+  validates :height, :presence => true
 
+  # Determine the screen's aspect ratio.  If it doesn't exist, calculate it
+  def aspect_ratio
+    if width.nil? || height.nil?
+      return { "width", "", "height", "" }
+    end
+    gcd = gcd(width,height)
+    aspect_width = width/gcd
+    aspect_height = height/gcd
+    return { "width", aspect_width, "height", aspect_height }
+  end
+
+  # Run Euclidean algorithm to find GCD
+  def gcd (a,b)
+    if b == 0
+      return a
+    end
+    return gcd (b, a.modulo(b) )
+  end
 end
+

app/views/screens/_form.html.erb

@@ -46,6 +46,18 @@
 				<%= f.collection_select :template_id, @templates, :id, :name %>
 			</div>
 		</div>
+                <div class="field">
+                        <%= f.label :width %>
+                        <div class="inputs">
+                                <%= f.text_field :width %>
+                        </div>
+                </div>
+                <div class="field">
+                        <%= f.label :height %>
+                        <div class="inputs">
+                                <%= f.text_field :height %>
+                        </div>
+                </div>
 	</div>
 
 	<div class="submit_bar actions">

app/views/screens/show.html.erb

@@ -22,7 +22,10 @@
   <b>Template:</b>
   <%= @screen.template.name %>
 </p>
-
+<p>
+  <b>resolution</b>
+  <%= @screen.width %> X <%= @screen.height %> (<%= @screen.aspect_ratio["width"] %>:<%=  @screen.aspect_ratio["height"] %>)
+</p>
 
 <%= link_to 'Edit', edit_screen_path(@screen) %> |
 <%= link_to 'Back', screens_path %>

db/migrate/20110317045358_add_resolution_to_screens.rb

@@ -0,0 +1,11 @@
+class AddResolutionToScreens < ActiveRecord::Migration
+  def self.up
+    add_column :screens, :width, :int
+    add_column :screens, :height, :int
+  end
+
+  def self.down
+    remove_column :screens, :height
+    remove_column :screens, :width
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended to check this file into your version control system.
 
-ActiveRecord::Schema.define(:version => 20110317033903) do
+ActiveRecord::Schema.define(:version => 20110317045358) do
 
   create_table "contents", :force => true do |t|
     t.string   "name"
@@ -94,6 +94,8 @@
     t.integer  "template_id"
     t.datetime "created_at"
     t.datetime "updated_at"
+    t.integer  "width"
+    t.integer  "height"
   end
 
   create_table "submissions", :force => true do |t|