Dano com efeito de gravidade.

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################################### XMS ########################################
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=begin
                                Gravity Effect

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Script criado pelo site XMS.
Created by XMS site.
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FUNÇÃO                       
 Permite que a apresentação do dano tenha o efeito de gravidade.

CUSTOMIZAÇÃO
=end
#-------------------------------------------------------------------------------
module XRXS_DAMAGE
  def damage_x_init_velocity
  #Quantidade de direçíµes que o dano poderá pular. 
  return 1.2 * (rand(5) - 2)
  end
  def damage_y_init_velocity
  #Velocidade do dano. 
  return 10
end
  #Força da gravidade. 
  GRAVITY = 0.98
end
#-------------------------------------------------------------------------------
module XRXS_DAMAGE
  def update
    super
    @damage_sprites  = [] if @damage_sprites.nil?
    @damage_durations = [] if @damage_durations.nil?
    if @_damage_sprite != nil and @_damage_sprite.visible
      x = damage_x_init_velocity
      y = damage_y_init_velocity
      d = @_damage_duration
      @damage_sprites.push(Sprite_Damage.new(@_damage_sprite, x, y, d))
      @_damage_sprite.visible = false
    end
    for damage_sprite in @damage_sprites
      damage_sprite.update
    end
    for i in 0...@damage_sprites.size
      @damage_sprites[i] = nil if @damage_sprites[i].disposed?
    end
    @damage_sprites.compact!
  end
  def dispose
    super
    if @damage_sprites != nil
      for damage_sprite in @damage_sprites
        damage_sprite.dispose
      end
    end
  end
end
class RPG::Sprite < Sprite
  include XRXS_DAMAGE
end
class Sprite_Damage < Sprite
  def initialize(sprite, init_x_speed, init_y_speed, duration)
    super(nil)
    self.bitmap = sprite.bitmap.dup unless sprite.bitmap.nil?
    self.opacity = sprite.opacity
    self.x = sprite.x
    self.y = sprite.y
    self.z = sprite.z
    self.ox = sprite.ox
    self.oy = sprite.oy
    @now_x_speed = init_x_speed
    @now_y_speed = init_y_speed
    @potential_x_energy = 0.0
    @potential_y_energy = 0.0
    @duration = duration
  end
  def update
    super
    n = self.oy + @now_y_speed
    if n <= 0
      @now_y_speed *= -1
      @now_y_speed /=  2
      @now_x_speed /=  2
    end
    self.oy  = [n, 0].max
    @potential_y_energy += XRXS_DAMAGE::GRAVITY
    speed = @potential_y_energy.floor
    @now_y_speed        -= speed
    @potential_y_energy -= speed
    @potential_x_energy += @now_x_speed
    speed = @potential_x_energy.floor
    self.ox            += speed
    @potential_x_energy -= speed
    @duration -= 1
    if @duration == 0
      self.dispose
    end
  end
end