Iseng2 RGSS3 (11) - Smooth Sliding

#==============================================================================
# ** Smooth_Slide
#------------------------------------------------------------------------------
#  This module provides basic module for smooth sliding. It can be implemented
# to any classes as long as they have x and y.
#==============================================================================
module Smooth_Slide
  # ---------------------------------------------------------------------------
  # Initialize smooth movement data
  # ---------------------------------------------------------------------------
  def init_smove
    @smooth_dur = 0     # Travel duration
    @accel_x = 0.0      # Acceleration X
    @accel_y = 0.0      # Acceleration Y
    @vel_x = 0.0        # Velocity X
    @vel_y = 0.0        # Velocity Y
    @sreal_x = self.x   # Real position X
    @sreal_y = self.y   # Real Position Y
    @starget_x = 0.0    # Target X
    @starget_y = 0.0    # Target Y
    @srev = false       # Reverse Flag
    @smove = false      # Moving Flag

    # The reason why I give 's' in front of most instance variables is for
    # uniqueness. Well, if there is any basic module / script out there that
    # also use same instance name, it may causes incompatibility

  end
  # ---------------------------------------------------------------------------
  # Do smooth movement
  # ---------------------------------------------------------------------------
  def smooth_move(x,y,dur,reverse = false)
    init_smove
    @srev = reverse
    @smove = true
    @smooth_dur = dur
    @sreal_x = self.x.to_f
    @sreal_y = self.y.to_f
    @starget_x = x
    @starget_y = y
    calc_accel
  end
  # ---------------------------------------------------------------------------
  # Do smooth slide
  # ---------------------------------------------------------------------------
  def smooth_slide(x,y,dur,reverse = false)
    tx = x + self.x
    ty = y + self.y
    smooth_move(tx,ty,dur,reverse)
  end
  # ---------------------------------------------------------------------------
  # Calculate acceleration
  # ---------------------------------------------------------------------------
  def calc_accel
    # Get travel distance
    dist_x = @starget_x - @sreal_x
    dist_y = @starget_y - @sreal_y

    # Calculate acceleration
    @accel_x = (dist_x/((@smooth_dur**2)/2.0))
    @accel_y = (dist_y/((@smooth_dur**2)/2.0))

    # If reverse, velocity started on max speed
    if @srev
      @vel_x = (@accel_x * @smooth_dur)
      @vel_y = (@accel_y * @smooth_dur)
    end
  end
  # ---------------------------------------------------------------------------
  # Execute end smooth
  # ---------------------------------------------------------------------------
  def end_smooth_slide
    init_smove
    puts "#{self.x} -- #{self.y}"
  end
  # ---------------------------------------------------------------------------
  # Update Smooth movement
  # ---------------------------------------------------------------------------
  def update_smove
    if @smove
      # If not reversed. Increase velocity on the first time executed
      if !@srev
        @vel_x += @accel_x
        @vel_y += @accel_y
      end

      # Give increment / decrement upon real position
      @sreal_x = (@starget_x > @sreal_x ?
        [@sreal_x + @vel_x, @starget_x].min :
        [@sreal_x + @vel_x, @starget_x].max)
      @sreal_y = (@starget_y > @sreal_y ?
        [@sreal_y + @vel_y, @starget_y].min :
        [@sreal_y + @vel_y, @starget_y].max)

      # Rounded real position
      self.x = @sreal_x.round
      self.y = @sreal_y.round

      # If reversed, decrease velocity after make a change to real position
      if @srev
        @vel_x -= @accel_x
        @vel_y -= @accel_y
      end

      # If target has reach it's destination, call end execution
      if (self.x == @starget_x && self.y == @starget_y) || @smooth_dur == 0
        end_smooth_slide
      end
    end
  end
  # ---------------------------------------------------------------------------
  # Get smooth moving flag
  # ---------------------------------------------------------------------------
  def smoving?
    @smove
  end

end

class Sprite
  include Smooth_Slide

  alias smooth_init initialize
  def initialize(v=nil)
    smooth_init(v)
    init_smove
  end

  alias smooth_update update
  def update
    smooth_update
    update_smove
  end

end

class Window
  include Smooth_Slide

  alias smooth_init initialize
  def initialize(*args)
    smooth_init(*args)
    init_smove
  end

  alias smooth_update update
  def update
    smooth_update
    update_smove
  end

end

def updates
  Graphics.update
  Input.update
  @spr.update
#~   puts "#{@spr.x} -- #{@spr.y}"
  if Input.trigger?(:C)
    @spr.smooth_slide(300,100,24,true)
  elsif Input.trigger?(:B)
    @spr.smooth_move(50,100,60)
  end
end

@spr = Sprite.new
@spr.bitmap = Cache.character("Actor1")
@spr.src_rect.set(Rect.new(0,0,32,32))

updates while true