Class: SnakeGame::BaitManager

Inherits:
Object
  • Object
show all
Includes:
Constants
Defined in:
lib/bait_manager.rb

Overview

Class for managing and updating baits (snake food)

Constant Summary

Constants included from Constants

Constants::EVASION, Constants::FPS, Constants::HEIGHT, Constants::NEXTLEVEL, Constants::STEP, Constants::WIDTH

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ BaitManager

Returns a new instance of BaitManager.



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# File 'lib/bait_manager.rb', line 12

def initialize
  @baits = []
  @images = ImageDatabase.new
end

Instance Attribute Details

#baits ⇒ Object

Returns the value of attribute baits.



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# File 'lib/bait_manager.rb', line 11

def baits
  @baits
end

Instance Method Details

#add_bait(position) ⇒ Object 



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# File 'lib/bait_manager.rb', line 26

def add_bait(position)
  @baits << (Bait.new position, @images.bait)
end

#calculate_random_movement ⇒ Object 



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# File 'lib/bait_manager.rb', line 62

def calculate_random_movement
  random = rand
  return Position.new(STEP, 0) if random > 0.75 # go right
  return Position.new(-STEP, 0) if random > 0.5 # go left
  return Position.new(0, STEP) if random > 0.25 # go down
  Position.new(0, -STEP) # go up
end

#draw ⇒ Object 



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# File 'lib/bait_manager.rb', line 70

def draw
  @baits.each(&:draw)
end

#free?(position, snake) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/bait_manager.rb', line 51

def free?(position, snake)
  free = true
  snake.snake_parts.each do |part|
    free = false if part.position == position
  end
  @baits.each do |bait|
    free = false if bait.position == position
  end
  free
end

#random_free_position(snake) ⇒ Object 



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# File 'lib/bait_manager.rb', line 30

def random_free_position(snake)
  loop do
    position = Position.new (rand * WIDTH).round(-1) % WIDTH,
                            (rand * HEIGHT).round(-1) % HEIGHT
    return position if free? position, snake
  end
end

#update(snake) ⇒ Object 



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# File 'lib/bait_manager.rb', line 17

def update(snake)
  if @baits.count.zero?
    position = random_free_position snake
    add_bait position
  else
    update_baits snake
  end
end

#update_baits(snake) ⇒ Object 



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# File 'lib/bait_manager.rb', line 38

def update_baits(snake)
  @baits.each do |bait|
    next if rand < EVASION
    loop do
      new_position = bait.position + calculate_random_movement
      if free? new_position, snake
        bait.position = new_position
        break
      end
    end
  end
end