Initial commit

Вместо змея пока что шарики, но и то хорошо

emitter.rb

@@ -0,0 +1,20 @@
+# 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)
+    @particles = particles
+  end
+  
+  def spawn (x, y)
+    @particles.create(x, y, rand * 360, (rand * 3)+3)
+  end
+
+  def draw
+    @particles.draw
+  end
+
+  def update
+    @particles.update
+  end
+end
+

particle.rb

@@ -0,0 +1,68 @@
+require './python.rb'
+
+# One particle is basically a sprite, that moves itself by speed every tick along an angle.
+# It also has a concept of decay, in how quickly the particle dies. In this case, the draw
+# command takes into account decay to shrink the particles and make them more translucent.
+class Particle 
+  def initialize(window, x, y, ang, speed, decay)
+    @x = x
+    @y = y
+    @angle =  90-ang
+    @speed = speed
+    @d_x = offset_x(@angle, @speed)
+    @d_y = offset_y(@angle, @speed)
+    @life = 1
+    @decay = decay
+    
+    radius = (rand * 10).floor
+    @img = Gosu::Image.new(window, Python.new(radius), false)
+  end
+  
+  def update
+    @x = @x + @d_x
+    @y = @y + @d_y
+    @life = @life - @decay
+    @angle += (@speed / 2)
+  end
+  
+  def dead?
+    @life <= 0
+  end
+  
+  def draw_layer(layer, color, x = nil, y = nil)
+     @img.draw_rot(x || @x, y || @y, layer, @angle, 0.5, 0.5, @life, @life, color, :default)    
+  end
+  
+  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))
+  end
+end
+
+
+# This class keeps track of our moving particles. It loads in a few white png files, and removes
+# dead particles during every tick. They could probably be garbage collected less frequently.
+class Particles
+  
+  def initialize(window)
+    @particles = []
+    @window = window
+  end
+  
+  def update
+    @particles.each {|p| p.update}
+    @particles.delete_if {|p| p.dead?}
+  end
+  
+  def draw
+    @particles.each {|p| p.draw}
+  end
+  
+  def create(x, y, angle, speed)
+    @particles << Particle.new(@window, x, y, angle, speed, 0.01)
+  end
+  
+end
+

particles.rb

@@ -0,0 +1,49 @@
+#!/usr/bin/ruby
+require 'gosu'
+include Gosu
+require './particle.rb'
+require './emitter.rb'
+
+# Our window size
+module Dimensions
+  Width, Height = 1280, 720
+end
+
+# Our layers for drawing.
+module ZOrder
+  Background, Shadow, Shape, Highlight = *0..3
+end
+
+class GameWindow < Gosu::Window
+  def initialize
+    super(Dimensions::Width, Dimensions::Height, false)
+    self.caption = "Particle Effects"
+    
+    @background_image = Gosu::Image.new(self, "images/background.png", true)
+    particles = Particles.new(self)
+    @emitter = Emitter.new(particles)
+  end
+
+  # Called every tick by gosu to update object positions
+  def update
+    @emitter.update
+  end
+
+  # Called every tick by gosu to draw things on the screen
+  def draw
+    @background_image.draw(0, 0, ZOrder::Background)
+    @emitter.draw
+  end
+  
+  # Quit on ESC
+  def button_down(id)
+    close if id == Gosu::Button::KbEscape
+    if id == Gosu::Button::MsLeft then
+      @emitter.spawn(self.mouse_x, self.mouse_y)
+    end
+  end
+end
+
+# Create the gosu window
+window = GameWindow.new
+window.show

python.rb

@@ -0,0 +1,20 @@
+# python who ate an elephant
+
+class Python
+  attr_reader :columns, :rows
+
+  def initialize radius
+    @columns = @rows = radius * 2
+    lower_half = (0...radius).map do |y|
+      x = Math.sqrt(radius**2 - y**2).round
+      right_half = "#{"\xff" * x}#{"\x00" * (radius - x)}"
+      "#{right_half.reverse}#{right_half}"
+    end.join
+    @blob = lower_half.reverse + lower_half
+    @blob.gsub!(/./) { |alpha| "\xff\xff\xff#{alpha}"}
+  end
+
+  def to_blob
+    @blob
+  end
+end