Turn Based Strategy Programming

[Brotherh0od]

How do you create a turn based game in RPG Maker XP?? (Include how to program the player and AI)

[Arrow]

If you mean something like a real time strategy game: No. Do not post here expecting a miracle.

If you mean a turn-based RPG battle system: It's in there by default.

[Blizzard]

He means SRPG like FF Tactics and similiar. Some have tried to make it, but haven't succeeded. I would give it a try, too, but I'm too short of time.

[Doctor Professor Nikolai]

Hmm...interesting...Well, I know one game you could make using this system, Monoply 

[Brotherh0od]

well...anyone else??

[GilgameshRO]

I made fair progress, but ultimately gave up when I hit making AI. It was a rather daunting task, and I'm just lazy.

[Blizzard]

AI is the hardest thing. Scripted AI might be more useful in this case.

[Sthrattoff]

Better to make an algorithm for the AI, like :

If monster hp less than ...% then he use his strongest spell
If monster hp is ... then he keeps walking to the nearest hero
If monster is next to hero, then he will attack
etc.

So your programming will be easier...

[&&&&&&&&&&&&&]

I don't think it that simple.

[Blizzard]

Here is my Enemy AI core for an ABS. Since I can't right now, maybe Sthratoff will take the time to explain it a little bit. It's not really hard, it just gets more complex with more available actions and states.

Code Select Expand

module Enemy_AI
 
# bosses have a special AI
BOSS_IDS = []
 
class Enemy_AI
 
  # setting all accessable variables
  attr_accessor :state
  attr_accessor :in_action
  attr_accessor :attacked
  attr_accessor :find_x
  attr_accessor :find_y
  attr_accessor :dmg
  attr_accessor :damage
  #----------------------------------------------------------------------------
  # AI initialization
  #----------------------------------------------------------------------------
  def initialize(maxhp, eva)
    # enemy's max HP
    @maxhp = maxhp
    # how likely is the enemy to flee
    @coward = eva.to_f
    # possible AI states:
    # 0 - idle/move
    # 1 - move
    # 2 - attack
    # 3 - skill
    # 4 - defend
    # 5 - run away
    # 6 - exception
    # 7 - memorized position
    # 8 - disappearing
    # 9 - in action
    @state = 0
    # collection of last damages to test if the player is stronger
    @dmg = []
    # damage sprite
    @damage = nil
    # an active enemy attacks with full power
    @active = false
    # memory flag
    @memory = false
    # attack shock count
    @attacked = 0
    # attack busy count
    @in_action = 0
    # fear shock count
    @fear = 0
    # last x and y of the player when lost out of sight
    @find_x = -1
    @find_y = -1
  end
  #----------------------------------------------------------------------------
  # in_range?(x, y, dir)
  #  x - x-coordinate
  #  y - y-coordinate
  #  dir - facing direction
  #  defines the enemy's behaviour depending on the fact if the player is
  #  inside a specific range
  #----------------------------------------------------------------------------
  def in_range?(x, y, dir, enemy)
    if @attacked > 0 # if enemy in attack shock/attacked
      # decrease shock count
      @attacked -= 1
      # cancel the attack
      @in_action = @attacked
      # set state
      @state = 6
      # return speed
      return 5
    end
    if @in_action > 0 # if enemy in attack shock/attacked
      # decrease shock count
      @in_action -= 1
      # set state
      @state = @state == 4 ? 4 : 9
      # return speed
      return 4
    end
    if judge or @fear > 0 # if enemy should flee or already fleeing
      # decrease the fear count
      @fear -= 1
      # set state
      @state = 5
      # return speed
      return 4
    end
    # calculates the distance
    d = Math.sqrt((($game_player.x+4)/8-x)**2 + (($game_player.y+4)/8-y)**2)
    # player was seen/heard
    perception = (can_precept_player?(x, y, dir) or $game_player.in_action > 0)
    # if player is in range of 5 squares and seen/heard or percepted or
    # already memorized by the enemy
    if d <= 5 and (perception or @memory)
      # player sighted, remembers that
      @memory = true
      # set the last coordinates of the player
      @find_x = $game_player.x
      @find_y = $game_player.y
      if d <= 1 # player in range, attack him
        action = what_to_do?(enemy)
        if action == []
          # set state
          @state = 2
          # return speed
          return 4
        else
          if action[0] == 0
            if action[1] == 0
              # set state
              @state = 2
              # return speed
              return 4
            else
              # set state
              @state = 4
              # return speed
              return 4
            end
          else
            # set state
            @state = 3
            # return speed
            return [4, action[2]]
          end
        end
      end
      # set state
      @state = 1
      # return speed
      return 4
    elsif @memory # has lost player out of sight, but remembers last position
      # difference between coordinates
      dx = x - (@find_x+4)/8
      dy = y - (@find_y+4)/8
      # if the enemy has reached the desired x and y
      if dx.abs <= 1 and dy.abs <= 1
        # player lost out of sight
        @memory = false
        # set idle state
        @state = 0
        # return speed
        return 3
      end
      # set state
      @state = 7
      # return speed
      return 4
    else # otherwise player is not in sight, be "idle"
      # set idle state
      @state = 0
      # return speed
      return 3
    end
    # set state either attack, skill or defend
    #@state = rand(3) + 2
    # return speed
    #return 4
  end
  #----------------------------------------------------------------------------
  # judge
  #  defines if the enemy has lost enough energy in an enough short period of
  #  time to flee
  #----------------------------------------------------------------------------
  def judge
    result = (@dmg.sum * 100 / @maxhp > 100.0 - @coward)
    @fear = ((@coward.to_f ** (1/4) + 1) * 20).to_i if result
    return result
  end
  #----------------------------------------------------------------------------
  # refresh
  #  removes the least recent damage accumulation, used by judge
  #----------------------------------------------------------------------------
  def refresh
    @dmg.shift unless @dmg.size == 0
  end
  #----------------------------------------------------------------------------
  # can_precept_player?(x, y, dir)
  #  x - x-coordinate
  #  y - y-coordinate
  #  dir - facing direction
  #  defines if the player can be heard or seen
  #----------------------------------------------------------------------------
  def can_precept_player?(x, y, dir)
    # calculate differences of x and y
    dx = x - ($game_player.x+4)/8.0
    dy = y - ($game_player.y+4)/8.0
    # check facing direction and return true if the player is inside the
    # seeing/hearing spectrum of the enemy
    case dir
    when 2
      return true if dy < 0 and (dx.abs < dy.abs or dx.abs <= 2 and dy.abs <= 2)
    when 4
      return true if dx < 0 and (dx.abs > dy.abs or dx.abs <= 2 and dy.abs <= 2)
    when 6
      return true if dx > 0 and (dx.abs > dy.abs or dx.abs <= 2 and dy.abs <= 2)
    when 8
      return true if dy > 0 and (dx.abs < dy.abs or dx.abs <= 2 and dy.abs <= 2)
    end
    return false
  end
  #----------------------------------------------------------------------------
  # get_a_effect
  #  processing of the skill priority
  #----------------------------------------------------------------------------
  def what_to_do?(enemy)
    return [] unless enemy.movable?
    available_actions = []
    rating_max = 0
    for action in enemy.actions
      next if enemy.hp * 100.0 / enemy.maxhp > action.condition_hp
      next if $game_party.max_level < action.condition_level
      switch_id = action.condition_switch_id
      next if switch_id > 0 and $game_switches[switch_id] == false
      available_actions.push(action)
      rating_max = action.rating if action.rating > rating_max
    end
    ratings_total = 0
    for action in available_actions
      if action.rating > rating_max - 3
        ratings_total += action.rating - (rating_max - 3)
      end
    end
    if ratings_total > 0
      value = rand(ratings_total)
      for action in available_actions
        if action.rating > rating_max - 3
          if value < action.rating - (rating_max - 3)
            kind = action.kind
            basic = action.basic
            skill_id = action.skill_id
            return [kind, basic, skill_id]
          else
            value -= action.rating - (rating_max - 3)
          end
        end
      end
    end
    return []
  end
 
end

end

[Sthrattoff]

@BanisherOfEden : I didn't say it was easy, I just say it makes your programming easier by focusing on what you must do to scripting the AI.
@Blizzard : Take a look,,,

[Sthrattoff]

Alright...
As far as I know...
This AI core are connected to Monster Database.
The enemy check their range from hero to perform attack...

That's what can I look this far...

[&&&&&&&&&&&&&]

sorry

[Blizzard]

Yes, it's only the definition of the behaviour. I use enhanced enemy events to actually perform and execute the bahaviour. The AI is only for determining whether the player is in view/hearing range, is still memorized, so they don't just give up when they lose him out of sight, attacking or ebing attacked what has a higher priority, BTW, that's why it is at the top of the in_range? method, etc.

[Sthrattoff]

@BanisherOfEden : No problem.
@Blizzard : Is there any possibilities to use the AI core on another CBS?

[Brotherh0od]

does anyone have a script that can program the main characters movement???

[Sthrattoff]

If you find a TBS scriplt, then there's one here already...