/examples/example5_gamestates_in_pure_gosu.rb

  1#!/usr/bin/env ruby
  2require 'rubygems' rescue nil
  3$LOAD_PATH.unshift File.join(File.expand_path(__FILE__), "..", "..", "lib")
  4require 'chingu'
  5include Gosu
  6
  7#
  8# Using Chingus game state mananger in pure Gosu.
  9#
 10class Game < Gosu::Window
 11  attr_reader :font
 12  def initialize
 13    $window = super(800,600,false)
 14    
 15    @font = Font.new($window, default_font_name(), 20)
 16    
 17    # Create our game state manager
 18    @manager = Chingu::GameStateManager.new
 19
 20    # Switch to first state
 21    @manager.switch_game_state(State1)
 22
 23    # Insert FadeTo state between every push, pop and switch
 24    @manager.transitional_game_state(Chingu::GameStates::FadeTo, :speed => 10, :game_state_manager => @manager)    
 25  end
 26
 27  def button_down(id)
 28    # This makes sure button_down(id) is called on the active game state
 29    # Enables input-handling in game states, you might wanna do the same with button_up()
 30    @manager.button_down(id)
 31    
 32    if @manager.current_game_state.class != Chingu::GameStates::FadeTo
 33    
 34      @manager.push_game_state(State1)  if(id==Button::Kb1)
 35      @manager.push_game_state(State2)  if(id==Button::Kb2)
 36      @manager.push_game_state(State3)  if(id==Button::Kb3)
 37      @manager.push_game_state(Chingu::GameStates::Pause)  if(id==Button::KbP)
 38      @manager.pop_game_state           if(id==Button::KbBackspace)
 39    end
 40    
 41    exit                             if(id==Button::KbEscape)
 42  end
 43  
 44  def update
 45    # This makes sure update() is called on the active game state
 46    @manager.update
 47  end
 48  
 49  def draw
 50    @font.draw("Game State Stack. 1-3 to push a game state. Backspace to pop.", 100, 200, 0)
 51    @manager.game_states.each_with_index do |game_state, index|
 52      @font.draw("#{index+1}) #{game_state.to_s}", 100, 220+index*20, 0)
 53    end
 54    
 55    # This makes sure draw() is called on the active game state
 56    @manager.draw
 57  end
 58end
 59
 60class State1 < Chingu::GameState
 61  def setup
 62    @spinner = ["|", "/", "-", "\\", "|", "/", "-", "\\"]
 63    @spinner_index = 0.0
 64  end
 65  
 66  def update
 67    @spinner_index += 0.1
 68    @spinner_index = 0    if @spinner_index >= @spinner.size
 69  end
 70  
 71  def draw
 72    $window.font.draw("Inside State1: #{@spinner[@spinner_index.to_i]}", 100, 100, 0)
 73  end
 74end
 75
 76class State2 < Chingu::GameState
 77  def setup
 78    @factor = 0.0
 79    @ticks = 0.0
 80  end
 81  
 82  def update
 83    @ticks += 0.01
 84    @factor = 1.5 + Math.sin(@ticks).to_f
 85  end
 86  
 87  def draw
 88    $window.font.draw("Inside State2 - factor_y: #{@factor.to_s}", 100, 100, 0, 1.0, @factor)
 89  end
 90end
 91
 92
 93class State3 < Chingu::GameState   
 94  def setup
 95    @factor = 0.0
 96    @ticks = 0.0
 97  end
 98  
 99  def update
100    @ticks += 0.01
101    @factor = 1.5 + Math.sin(@ticks).to_f
102  end  
103  def draw
104    $window.font.draw("Inside State3 - factor_x: #{@factor.to_s}", 100, 100, 0, @factor, 1.0)
105  end
106end
107
108
109Game.new.show