Module: Chingu::Traits::Timer

Defined in:
lib/chingu/traits/timer.rb

Overview

A chingu trait providing timer-methods to its includer, examples:

during(300) { @color = Color.new(0xFFFFFFFF) }   # forces @color to white ever update for 300 ms
after(400) { self.destroy! }                     # destroy object after 400 ms
between(1000,2000) { self.rotate(10) }           # starting after 1 second, call rotate(10) each update during 1 second

All the above can be combined with a ‘then { do_something }’. For example, a classic shmup damage effect:

during(100) { @color.alpha = 100 }.then { @color.alpha = 255 }

Instance Method Summary collapse

Instance Method Details

#after(time, &block) ⇒ Object 



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# File 'lib/chingu/traits/timer.rb', line 53

def after(time, &block)
  ms = Gosu::milliseconds()
  @_last_timer = [ms + time, nil, block]
  @_timers << @_last_timer
  self
end

#between(start_time, end_time, &block) ⇒ Object 



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# File 'lib/chingu/traits/timer.rb', line 60

def between(start_time, end_time, &block)
  ms = Gosu::milliseconds()
  @_last_timer = [ms + start_time, ms + end_time, block]
  @_timers << @_last_timer
  self
end

#during(time, &block) ⇒ Object 



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# File 'lib/chingu/traits/timer.rb', line 46

def during(time, &block)
  ms = Gosu::milliseconds()
  @_last_timer = [ms, ms + time, block]
  @_timers << @_last_timer
  self
end

#every(delay, &block) ⇒ Object 



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# File 'lib/chingu/traits/timer.rb', line 74

def every(delay, &block)
  ms = Gosu::milliseconds()
  @_repeating_timers << [ms + delay, delay, block]
end

#setup_trait(options) ⇒ Object 



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# File 'lib/chingu/traits/timer.rb', line 36

def setup_trait(options)        
  #
  # Timers are saved as an array of arrays where each entry contains:
  # [start_time, end_time (or nil if one-shot), &block]
  #
  @_timers = Array.new
  @_repeating_timers = Array.new
  super
end

#then(&block) ⇒ Object 



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# File 'lib/chingu/traits/timer.rb', line 67

def then(&block)
  # ...use one-shots start_time for our trailing "then".
  # ...use durable timers end_time for our trailing "then".
  start_time = @_last_timer[1].nil? ? @_last_timer[0] : @_last_timer[1]
  @_timers << [start_time, nil, block]
end

#update_trait ⇒ Object 



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# File 'lib/chingu/traits/timer.rb', line 79

def update_trait
  ms = Gosu::milliseconds()
  
  @_timers.each do |start_time, end_time, block|
    block.call  if ms > start_time && (end_time == nil || ms < end_time)
  end
          
  index = 0
  @_repeating_timers.each do |start_time, delay, block|
    if ms > start_time
      block.call  
      @_repeating_timers[index] = [ms + delay, delay, block]
    end
    index += 1
  end

  # Remove one-shot timers (only a start_time, no end_time) and all timers which have expired
  @_timers.reject! { |start_time, end_time, block| (ms > start_time && end_time == nil) || (end_time != nil && ms > end_time) }

  super
end