From: Greg Coit <gregcoit@...>
Date: 2006-04-23T08:55:40+09:00
Subject: Re: Thinking in OO

In my latest attempt at writing a bot, my objects are radar, gun and tank.

methods are things like increase (scan), decrease (scan), reverse, adjust, etc.

There's also a bit of procedural code in the main (tick) method to
know what object to call with what method.  Is that acceptable in OO?

Code follows - not the smartest bot in the world (he doesn;t even move
yet - trying to get the radar to lock-on consitently), but i'm hoping
it's a good start that I can add to.

Any/all suggestion and criticism are very welcome!

Greg

require 'robot'

#in this script, heading is absolute (0-360), dir (direction) is
relative (+- and probably no more than 60)

#available options:
#
#state:
#	team
#	battlefield_height
#	battlefield_width
#	energy
#	gun_heading
#	gun_heat
#	heading
#	size
#	radar_heading
#	time
#	game_over
#	speed
#	x
#	y
#actions:
#	accelerate
#	stop
#	fire
#	turn
#	turn_gun
#	turn_radar
#	broadcast
#	say
#events:
#	broadcast
#       got_hit
#	robot_scanned

####### Need Unit Tests!!!!!!!!

class GoofeyDuck
   include Robot

  def initialize
    @got_hit = 0
    @found
    @seen #found previous round...

    @radar = Radar.new
    @gun = Gun.new
    @tank = Tank.new


  end

  def tick(events)

    @got_hit = events['got_hit']
    @found =  events['robot_scanned'] if (!events['robot_scanned'].empty?)

    #set radar
    if (@found)
      @radar.decrease(1) unless (@radar.dir.abs <= 1)
      @radar.reverse
      @seen = 1
      say "Locked"
    elsif (@seen)
      @radar.increase(3)
      @radar.reverse
      @seen = !@seen
      say "Dang, Lost em"
    else
      @radar.increase(2)
      say "Tracking...."
    end
    @radar.dir = verify(@radar.dir, @radar.max)

    #set gun
    @gun.adjust(@radar.mid(radar_heading), gun_heading)
    @gun.dir = verify(@gun.dir, @gun.max)

    #fire or no?
    if (@found)
      @gun.fire += 0.1
    else
      @gun.fire -= 0.1 unless (@gun.fire <= 0)
    end

    @gun.fire = verify(@gun.fire, 3)

    #pass results
    turn_radar(verify(@radar.adjust(@gun.dir), @radar.max)) #adjust radar to gun
    turn_gun(@gun.dir)
    turn(@tank.dir)
    accelerate(@tank.vel)
    fire(@gun.fire)
    say "Uh oh" if (energy <= 10)

    puts @gun.fire

    #reset
    @found = !@found if (@found)

  end

  def verify(dir, max)
    if (dir > max)
      dir = max
    elsif (dir.abs > max)
      dir = (max * -1)
    end
  dir
  end

end

class Radar
  include Robot

  attr_reader :dir, :max
  attr_writer :dir

  def initialize
    @dir = 60
    @max = 60 #max delta
  end

  def increase(amt)
    z = @dir <=> 0
    @dir += (amt * z)
  end

  def decrease(amt)
    z = @dir <=> 0
    @dir -= (amt * z)
  end

  def reverse
    @dir *= -1
  end

  def adjust(gun)
    @dir - gun
  end

  def mid(head) #in degrees....
    head + (@dir/2)
  end

end

class Gun
  include Robot

  attr_reader :dir, :fire, :max
  attr_writer :dir, :fire

  def initialize
    @dir = 0
    @max = 30 #max delta
    @fire = 0.1
  end

  def adjust(target, gun_head)
    @dir = target - gun_head
  end

end

class Tank
  include Robot

  attr_reader :dir, :vel
  attr_writer :dir, :vel

  def initialize
    @dir = 0
    @max = 10 #max delta
    @vel = 0
  end

end