New linear gradient mixin and support functions. Radial gradient and browser testing are still pending.

frameworks/compass/stylesheets/compass/css3/_gradient.sass

@@ -6,35 +6,39 @@
   background: -moz-#{!type}-gradient(#{!gradient})
 
 //*
-  // This will yeild a radial gradient with an apparent specular highlight
+  // This will yield a radial gradient with an apparent specular highlight
   +radial-gradient("45 45, 10, 52 50, 30", Cyan, DodgerBlue)
     
 =radial-gradient(!coords, !color1, !color2, !color_stop = false)
   +gradient("radial", !coords, !color1, !color2, !color_stop)
 
 //* 
-  // This yields a linear gradient spanning from !start to !end coordinates
-  +linear-gradient("left top", "left bottom", #fff, #ddd)
-
-=linear-gradient(!start, !end, !color1, !color2, !color_stop = false)
-  !coords = !start + ", " + !end
-  +gradient("linear", !coords, !color1, !color2, !color_stop)
-
-//*
-  // This yields a gradient starting at the top with #fff, ending in #aaa
-  +v-gradient(#fff, #aaa)
-  // Same as above but with a #ccc at the halfway point
-  +v-gradient(#fff, #aaa, color_stop(50%, #ccc))
-  // Same as the first example but with #ccc at the 30% from the top, and #bbb at 70% from the top
-  +v-gradient(#fff, #aaa, color_stop(30%, #ccc, 70%, #bbb))
-
-=v-gradient(!color1, !color2, !color_stop = false)
-  +linear-gradient("left top", "left bottom", !color1, !color2, !color_stop)
-
-//* 
-  // This yields a horizontal linear gradient spanning from left to right
-  // It can be used just like v-gradient above
-  h-gradient(#fff, #ddd)
+  // This yields a linear gradient spanning from top to bottom
+  +linear-gradient(color_stops(white, black))
   
-=h-gradient(!color1, !color2, !color_stop = false)
-  +linear-gradient("left top", "right top", !color1, !color2, !color_stop)
+  // This yields a linear gradient spanning from bottom to top
+  +linear-gradient(color_stops(white, black), "bottom")
+
+  // This yields a linear gradient spanning from left to right
+  +linear-gradient(color_stops(white, black), "left")
+
+  // This yields a linear gradient starting at white passing
+  // thru blue at 33% down and then to black
+  +linear-gradient(color_stops(white, blue 33%, black))
+
+  // This yields a linear gradient starting at white passing
+  // thru blue at 33% down and then to black at 67% until the end
+  +linear-gradient(color_stops(white, blue 33%, black 67%))
+
+=linear-gradient(!color_stops, !start = "top")
+  // Firefox's gradient api is nice.
+  // Webkit's gradient api sucks -- hence these backflips:
+  !end = grad_opposite_position(!start)
+  !start_color = grad_start_color(!color_stops)
+  !end_color = grad_end_color(!color_stops)
+  !webkit_stops = grad_color_stops(!color_stops)
+  !gradient= "#{grad_point(!start)}, #{grad_point(!end)}, from(#{!start_color}), to(#{!end_color})"
+  @if !webkit_stops
+    !gradient= !gradient + ", " + !webkit_stops
+  background-image: -webkit-gradient(linear, #{!gradient})
+  background-image: -moz-linear-gradient(#{!start}, #{!color_stops})

lib/compass/sass_extensions/functions.rb

@@ -1,7 +1,7 @@
 module Compass::SassExtensions::Functions
 end
 
-%w(selectors enumerate urls display inline_image color_stop font_files).each do |func|
+%w(selectors enumerate urls display inline_image gradient_support font_files).each do |func|
   require "compass/sass_extensions/functions/#{func}"
 end
 
@@ -11,7 +11,7 @@ module Sass::Script::Functions
   include Compass::SassExtensions::Functions::Urls
   include Compass::SassExtensions::Functions::Display
   include Compass::SassExtensions::Functions::InlineImage
-  include Compass::SassExtensions::Functions::ColorStop
+  include Compass::SassExtensions::Functions::GradientSupport::Functions
   include Compass::SassExtensions::Functions::FontFiles
 end
 

lib/compass/sass_extensions/functions/color_stop.rb

@@ -1,10 +0,0 @@
-module Compass::SassExtensions::Functions::ColorStop
-  def color_stop(*args)
-    raise Sass::SyntaxError, "An even number of arguments must be passed to color-stop()" unless args.size % 2 == 0
-    stops = []
-    while args.size > 0
-      stops << "color-stop(#{args.shift}, #{args.shift})"
-    end
-    Sass::Script::String.new(stops.join(", "))
-  end
-end

lib/compass/sass_extensions/functions/gradient_support.rb

@@ -0,0 +1,123 @@
+module Compass::SassExtensions::Functions::GradientSupport
+
+  class List < Sass::Script::Literal
+    attr_accessor :values
+    def initialize(*values)
+      self.values = values
+    end
+    def inspect
+      to_s
+    end
+    def to_s
+      values.map{|v| v.to_s}.join(", ")
+    end
+  end
+
+  class ColorStop < Sass::Script::Literal
+    attr_accessor :color, :stop
+    def initialize(color, stop = nil)
+      self.color, self.stop = color, stop
+    end
+    def inspect
+      to_s
+    end
+    def to_s
+      s = "#{color}"
+      if stop
+        s << " "
+        s << stop.times(Sass::Script::Number.new(100)).to_s
+        s << "%"
+      end
+      s
+    end
+  end
+
+  module Functions
+    def grad_opposite_position(position)
+      opposite = position.value.split(/ +/).map do |pos|
+        case pos
+        when "top" then "bottom"
+        when "bottom" then "top"
+        when "left" then "right"
+        when "right" then "left"
+        else
+          raise Sass::SyntaxError, "Cannot determine the opposite of #{pos}"
+        end
+      end
+      Sass::Script::String.new(opposite.join(" "))
+    end
+    def grad_color_stops(color_list)
+      positions = color_list.values.map{|c| [c.stop && c.stop.value, c.color]}
+      # fill in the blank positions
+      positions[0][0] = 0 unless positions.first.first
+      positions[positions.size - 1][0] = 1 unless positions.last.first
+      for i in 0...positions.size
+        if positions[i].first.nil?
+          num = 2.0
+          for j in (i+1)...positions.size
+            if positions[j].first
+              positions[i][0] = positions[i-1].first + (positions[j].first - positions[i-1].first) / num
+              break
+            else
+              num += 1
+            end
+          end
+        end
+      end
+      positions = positions[1..-1] if positions.first.first == 0.0
+      positions = positions[0..-2] if positions.last.first == 1.0
+      if positions.empty?
+        # We return false here since sass has no nil.
+        Sass::Script::Bool.new(false)
+      else
+        color_stops = positions.map {|pos| "color-stop(#{Sass::Script::Number.new((pos.first*10000).round/100.0).to_s}%, #{pos.last})"}
+        Sass::Script::String.new(color_stops.join(", "))
+      end
+    end
+    def grad_start_color(color_list)
+      color_list.values.first.color
+    end
+    def grad_end_color(color_list)
+      color_list.values.last.color
+    end
+    def grad_point(position)
+      position = position.value
+      position = if position[" "]
+        position
+      else
+        case position
+        when /top|bottom/
+          "#{position} left"
+        when /left|right/
+          "top #{position}"
+        end
+      end
+      Sass::Script::String.new position.gsub(/top/, "0%").gsub(/bottom/, "100%").gsub(/left/,"0%").gsub(/right/,"100%")
+    end
+    def color_stops(*args)
+      List.new(*args.map do |arg|
+        case arg
+        when Sass::Script::Color
+          ColorStop.new(arg)
+        when Sass::Script::String
+          color, stop = arg.value.split(/ +/, 2)
+          color = Sass::Script::Parser.parse(color, 0, 0)
+          if stop =~ /^(\d+)?(?:\.(\d+))?(%)?$/
+            integral, decimal, percent = $1, $2, $3
+            number = "#{integral || 0}.#{decimal || 0}".to_f
+            number = number / 100 if percent
+            if number > 1
+              raise Sass::SyntaxError, "A color stop location must be between 0#{"%" if percent} and 1#{"00%" if percent}. Got: #{stop}"
+            end
+            stop = Sass::Script::Number.new(number)
+          elsif !stop.nil?
+            raise Sass::SyntaxError, "A color stop location must be between 0 and 1 or 0% and 100%. Got: #{stop}"          
+          end
+          ColorStop.new(color, stop)
+        else
+          raise Sass::SyntaxError, "Not a valid color stop: #{arg}"          
+        end
+      end)
+    end
+  end
+end

test/compass_test.rb

@@ -42,7 +42,7 @@ class CompassTest < Test::Unit::TestCase
       each_css_file(proj.css_path) do |css_file|
         assert_no_errors css_file, 'compass'
       end
-      assert_renders_correctly :reset, :layout, :utilities
+      assert_renders_correctly :reset, :layout, :utilities, :gradients
     end
   end
 

test/fixtures/stylesheets/compass/css/gradients.css

@@ -0,0 +1,43 @@
+.linear-1 {
+  background-image: -webkit-gradient(linear, 0% 0%, 100% 0%, from(#dddddd), to(#aaaaaa));
+  background-image: -moz-linear-gradient(top, #dddddd, #aaaaaa); }
+
+.linear-2 {
+  background-image: -webkit-gradient(linear, 0% 0%, 0% 100%, from(#dddddd), to(#aaaaaa));
+  background-image: -moz-linear-gradient(left, #dddddd, #aaaaaa); }
+
+.linear-3 {
+  background-image: -webkit-gradient(linear, 0% 0%, 100% 100%, from(#dddddd), to(#aaaaaa));
+  background-image: -moz-linear-gradient(top left, #dddddd, #aaaaaa); }
+
+.linear-4 {
+  background-image: -webkit-gradient(linear, 0% 100%, 100% 0%, from(#dddddd), to(#aaaaaa));
+  background-image: -moz-linear-gradient(top right, #dddddd, #aaaaaa); }
+
+.linear-5 {
+  background-image: -webkit-gradient(linear, 0% 0%, 100% 0%, from(#dddddd), to(#aaaaaa), color-stop(50%, #cccccc));
+  background-image: -moz-linear-gradient(top, #dddddd, #cccccc, #aaaaaa); }
+
+.linear-6 {
+  background-image: -webkit-gradient(linear, 0% 0%, 100% 0%, from(#dddddd), to(#aaaaaa), color-stop(20%, #cccccc));
+  background-image: -moz-linear-gradient(top, #dddddd, #cccccc 20%, #aaaaaa); }
+
+.linear-7 {
+  background-image: -webkit-gradient(linear, 0% 0%, 100% 0%, from(#dddddd), to(#aaaaaa), color-stop(20%, #cccccc), color-stop(60%, #eeeeee));
+  background-image: -moz-linear-gradient(top, #dddddd, #cccccc 20%, #eeeeee, #aaaaaa); }
+
+.linear-8 {
+  background-image: -webkit-gradient(linear, 0% 0%, 100% 0%, from(#dddddd), to(#aaaaaa), color-stop(80%, #dddddd));
+  background-image: -moz-linear-gradient(top, #dddddd 80%, #aaaaaa); }
+
+.linear-9 {
+  background-image: -webkit-gradient(linear, 0% 0%, 100% 0%, from(#dddddd), to(#aaaaaa), color-stop(20%, #aaaaaa));
+  background-image: -moz-linear-gradient(top, #dddddd, #aaaaaa 20%); }
+
+.linear-10 {
+  background-image: -webkit-gradient(linear, 0% 0%, 100% 0%, from(#dddddd), to(#aaaaaa), color-stop(40%, #dddddd), color-stop(50%, #aaaaaa));
+  background-image: -moz-linear-gradient(top, #dddddd 40%, #aaaaaa 50%); }
+
+.linear-11 {
+  background-image: -webkit-gradient(linear, 0% 0%, 100% 0%, from(#dddddd), to(#aaaaaa), color-stop(40%, #dddddd), color-stop(45%, black), color-stop(50%, #aaaaaa));
+  background-image: -moz-linear-gradient(top, #dddddd 40%, black, #aaaaaa 50%); }

test/fixtures/stylesheets/compass/sass/gradients.sass

@@ -0,0 +1,24 @@
+@import compass/css3.sass
+
+.linear-1
+  +linear-gradient(color_stops(#ddd, #aaa))
+.linear-2
+  +linear-gradient(color_stops(#ddd, #aaa), "left")
+.linear-3
+  +linear-gradient(color_stops(#ddd, #aaa), "top left")
+.linear-4
+  +linear-gradient(color_stops(#ddd, #aaa), "top right")
+.linear-5
+  +linear-gradient(color_stops(#ddd, #ccc, #aaa))
+.linear-6
+  +linear-gradient(color_stops(#ddd, #ccc 20%, #aaa))
+.linear-7
+  +linear-gradient(color_stops(#ddd, #ccc 20%, #eee, #aaa))
+.linear-8
+  +linear-gradient(color_stops(#ddd 80%, #aaa))
+.linear-9
+  +linear-gradient(color_stops(#ddd, #aaa 20%))
+.linear-10
+  +linear-gradient(color_stops(#ddd 40%, #aaa 50%))
+.linear-11
+  +linear-gradient(color_stops(#ddd 40%, #000, #aaa 50%))