tried to make a fountain point

ellipsoid.rb

@@ -4,7 +4,7 @@ class Ellipsoid
   def initialize radius
     @columns = @rows = radius * 2
     lower_half = (0...radius).map do |y|
-      x = Math.sqrt(1 - y**2/radius**2)
+      x = Math.sqrt(1 - y**2/radius**2).floor
       right_half = "#{"\xff" * x}#{"\x00" * (radius - x)}"
       "#{right_half.reverse}#{right_half}"
     end.join

emitter.rb

@@ -1,12 +1,13 @@
 # An emitter simply emits particles at a regular interval. In this case, every
 # time spawn is called, a new particle is generated with a random angle of movement and speed.
 class Emitter  
-  def initialize(particles)
+  def initialize(particles, fountain)
     @particles = particles
+    @fountain = fountain
   end
   
   def spawn (x, y)
-    @particles.create(x, y, rand * 360, (rand * 3)+3)
+    @particles.create(x, y, rand * 360, (1/@fountain.distance(x,y) * 6)+3)
   end
 
   def draw

fountain.rb

@@ -0,0 +1,10 @@
+class Fountain
+  def initialize (x = 0, y = 0)
+    @x = x
+    @y = y
+  end
+
+  def distance (x, y)
+    return Math.sqrt((@x-x)**2 + (@y-y)**2).floor
+  end
+end

particle.rb

@@ -36,8 +36,8 @@ class Particle
   def draw
     return if dead?
     draw_layer(ZOrder::Shadow, Gosu::Color.new((@life * 128).floor,0,0,0), @x+2, @y+2)
-    draw_layer(ZOrder::Shape, Gosu::Color.new((@life * 255).floor, 255,255,0))
-    draw_layer(ZOrder::Highlight, Gosu::Color.new((@life * 20).floor,255,255,255))
+    draw_layer(ZOrder::Shape, Gosu::Color.new((@life * 255).floor, 128,128,128))
+    draw_layer(ZOrder::Highlight, Gosu::Color.new((@life * 20).floor,200,200,200))
   end
 end
 

particles.rb

@@ -2,6 +2,7 @@
 require 'gosu'
 include Gosu
 require './particle.rb'
+require './fountain.rb'
 require './emitter.rb'
 
 # Our window size
@@ -21,7 +22,8 @@ class GameWindow < Gosu::Window
     
     @background_image = Gosu::Image.new(self, "images/background.png", true)
     particles = Particles.new(self)
-    @emitter = Emitter.new(particles)
+    @fountain = Fountain.new
+    @emitter = Emitter.new(particles, @fountain)
   end
 
   # Called every tick by gosu to update object positions