[XP Script] XP Wave Effect - Printable Version

Code:
#========================================

# XP Wave Effect

#----------------------------------------

#by:      zecomeia

#date:    01/03/2010

#for:     RGSS

#version: 1.0

#www.colmeia-do-ze.blogspot.com

#----------------------------------------

=begin

Reproduction of the VX's wave effect

(see the help file of the RPGMaker VX 

in the RGSS manual reference topic)

=end



#==============#

# Sprite class #

#==============#

class Sprite

  

  include Math

  

  attr_accessor   :wave_amp

  attr_accessor   :wave_length

  attr_accessor   :wave_speed

  attr_accessor   :wave_phase

  attr_accessor   :temp_bitmap

  

  alias initialize default_initialize rescue nil

  alias default_initialize initialize

  def initialize(viewport=nil)

    @wave_amp = 0

    @wave_length = 180

    @wave_speed = 360

    @wave_phase = 0.0

    default_initialize(viewport)

    @temp_bitmap = nil

  end

  

  alias update default_update rescue nil

  alias default_update update  

  def update()

    # the wave effect only works if wave_amp

    # propertie is a number more than zero

    wave_effect if @wave_amp > 0

    default_update()

  end

  

  # Return the width of image, because when use

  # obj.bitmap.width the value will be more than

  # the original value(because effect)

  def width()

    return (self.bitmap.width - @wave_amp * 2)

  end

    

  #---------------

  # Wave Effect

  #---------------

  def wave_effect()

    return if self.bitmap.nil?

    @temp_bitmap = self.bitmap if @temp_bitmap.nil?

    cw = @temp_bitmap.width + (@wave_amp * 2)

    ch = @temp_bitmap.height

    # Follow the VX wave effect, each horizontal line

    # has 8 pixel of height. This device provides less

    # lag in game.

    divisions = @temp_bitmap.height / 8

    divisions += 1 if @temp_bitmap.height % 8 != 0

    self.bitmap = Bitmap.new(cw, ch)

    for i in 0..divisions

      x = @wave_amp * Math.sin(i * 2 * PI / (@wave_length / 8).to_i + Math.deg_to_rad(@wave_phase))

      src_rect = Rect.new(0, i*8, @temp_bitmap.width, 8)

      dest_rect = Rect.new(@wave_amp + x, i * 8, @temp_bitmap.width, 8)

      self.bitmap.stretch_blt(dest_rect, @temp_bitmap, src_rect)

    end

    # frame rate: VX = 60 | XP = 40

    # wave speed compatibility VX to XP: wave_speed * 60/40

    # then: wave_speed * 1.5

    @wave_phase += @wave_speed * 1.5 / @wave_length

    @wave_phase -= 360 if @wave_phase > 360

    @wave_phase += 360 if @wave_phase < 0

  end

  

end



#=============#

# module Math #

#=============#

module Math

  

  #-------------------------------

  # Conversion Degree to Radian

  #-------------------------------

  def Math.deg_to_rad(deg)

    return (deg * PI) / 180.0

  end

  

end