Multi Layer Fog (VX Ace)

#============================================================================
# Multi Layer Fog
# v1.0 by Shaz
#----------------------------------------------------------------------------
# This script lets you add one or more layers of fog to a map.
# You can add vertical and/or horizontal scrolling to each fog layer.
# You can have fog appear on top of the map or behind the map (above the
# parallax layer).
# You can adjust the fog's opacity and tone over time.
#----------------------------------------------------------------------------
# To Install:
# Copy and paste into a new script slot in Materials.  This script aliases
# existing methods, so can go below all other custom scripts.
#----------------------------------------------------------------------------
# To Use:
# Create a Fogs folder inside your game's Graphics folder, and paste your
# fog png files there.
#
# To add fog to a map, use the following in a Call Script event command:
#    show_fog(number, "filename", hue, opacity, blend_type, zoom,
#      speed-x, speed-y, z)
# - only number and filename are mandatory
# - fog is added like pictures - the number is simply an id (an array index),
#   and if you don't specify the z value, fog with a higher number/id is drawn
#   over fog with a lower number/id
# - z position defaults to above the player.  If you want to show fog above the
#   parallax layer but behind the map, use a negative value for z.  The
#   parallax is drawn at -100
#
# To change fog tone, use the following in a Call Script event command:
#    tint_fog(number, red, green, blue, gray, duration)
#
# To change the fog opacity, use the following in a Call Script event command:
#    fade_fog(number, opacity, duration)
#
# To remove fog, use the following in a Call Script event command:
#    erase_fog(number)
#
# By default fog will be removed when you change maps, and battle screens
# will have the same fog as the map.  Change the CUSTOMIZATION options below
# if you do not want this.
#----------------------------------------------------------------------------
# Updates
# 2021.02.27 Fixed blend type when transferring to other maps (thanks to BrokenAnkle21)
#----------------------------------------------------------------------------
# Terms:
# Use in free or commercial games
# Credit Shaz
#============================================================================

#============================================================================
# CUSTOMIZATION
#
# Set this to true or false to show (or not show) fog in the battle screen
BATTLE_FOGS = true

# Set this to true or false to clear (or not clear) fogs on transfer to new map
CLEAR_ON_TRANSFER = true

# DO NOT CHANGE ANYTHING BELOW THIS LINE
#============================================================================


module Cache
  #--------------------------------------------------------------------------
  # * Get Fog
  #--------------------------------------------------------------------------
  def self.fog(filename, hue)
    load_bitmap("Graphics/Fogs/", filename, hue)
  end
end

class Game_Screen
  #--------------------------------------------------------------------------
  # * Public Instance Variables
  #--------------------------------------------------------------------------
  attr_reader   :fogs
  #--------------------------------------------------------------------------
  # * Object Initialization
  #--------------------------------------------------------------------------
  alias shaz_multi_fog_game_screen_initialize initialize
  def initialize
    @fogs = Game_Fogs.new
    shaz_multi_fog_game_screen_initialize
  end
  #--------------------------------------------------------------------------
  # * Clear
  #--------------------------------------------------------------------------
  alias shaz_multi_fog_game_screen_clear clear
  def clear
    shaz_multi_fog_game_screen_clear
    clear_fogs
  end
  #--------------------------------------------------------------------------
  # * Clear Fogs
  #--------------------------------------------------------------------------
  def clear_fogs
    @fogs.each {|fog| fog.erase}
  end
  #--------------------------------------------------------------------------
  # * Frame Update
  #--------------------------------------------------------------------------
  alias shaz_multi_fog_game_screen_update update
  def update
    shaz_multi_fog_game_screen_update
    update_fogs
  end
  #--------------------------------------------------------------------------
  # * Object Initialization
  #--------------------------------------------------------------------------
  def update_fogs
    @fogs.each {|fog| fog.update}
  end
end

class Game_Fog
  #--------------------------------------------------------------------------
  # * Public Instance Variables
  #--------------------------------------------------------------------------
  attr_reader   :number
  attr_reader   :name
  attr_reader   :hue
  attr_reader   :opacity
  attr_reader   :blend_type
  attr_reader   :zoom
  attr_reader   :sx
  attr_reader   :sy
  attr_reader   :ox
  attr_reader   :oy
  attr_reader   :tone
  attr_reader   :z
  #--------------------------------------------------------------------------
  # * Object Initialization
  #--------------------------------------------------------------------------
  def initialize(number)
    @number = number
    init_basic
    init_movement
    init_tone
    init_opacity
  end
  #--------------------------------------------------------------------------
  # * Initialize Basic Variable
  #--------------------------------------------------------------------------
  def init_basic
    @name = ""
    @hue = 90
    @blend_type = 0
    @zoom = 200
    @sx = @sy = 0
  end
  #--------------------------------------------------------------------------
  # * Initialize Movement Variable
  #--------------------------------------------------------------------------
  def init_movement
    @ox = @oy = 0
  end
  #--------------------------------------------------------------------------
  # * Initialize Tone
  #--------------------------------------------------------------------------
  def init_tone
    @tone = Tone.new
    @tone_target = Tone.new
    @tone_duration = 0
  end
  #--------------------------------------------------------------------------
  # * Initialize Opacity
  #--------------------------------------------------------------------------
  def init_opacity
    @opacity = 64.0
    @opacity_target = 64.0
    @opacity_duration = 0
  end
  #--------------------------------------------------------------------------
  # * Show Fog
  #--------------------------------------------------------------------------
  def show(name, hue, opacity, blend_type, zoom, sx, sy, z)
    @name = name
    @hue = hue
    @opacity = opacity
    @blend_type = blend_type
    @zoom = zoom
    @sx = sx
    @sy = sy
    @z = z.nil? ? 300 + @number : z
    init_movement
  end
  #--------------------------------------------------------------------------
  # * Start Changing Tone
  #--------------------------------------------------------------------------
  def start_tone_change(tone, duration)
    @tone_target = tone.clone
    @tone_duration = duration
    @tone = @tone_target.clone if @tone_duration == 0
  end
  #--------------------------------------------------------------------------
  # * Start Opacity Change
  #--------------------------------------------------------------------------
  def start_opacity_change(opacity, duration)
    @opacity_target = opacity * 1.0
    @opacity_duration = duration
    @opacity = @opacity_target if @opacity_duration == 0
  end
  #--------------------------------------------------------------------------
  # * Erase Fog
  #--------------------------------------------------------------------------
  def erase
    @name = ""
  end
  #--------------------------------------------------------------------------
  # * Frame Update
  #--------------------------------------------------------------------------
  def update
    update_move
    update_tone_change
    update_opacity_change
  end
  #--------------------------------------------------------------------------
  # * Update Fog Move
  #--------------------------------------------------------------------------
  def update_move
    @ox -= @sx / 8.0
    @oy -= @sy / 8.0
  end
  #--------------------------------------------------------------------------
  # * Update Fog Tone Change
  #--------------------------------------------------------------------------
  def update_tone_change
    return if @tone_duration == 0
    d = @tone_duration
    target = @tone_target
    @tone.red = (@tone.red * (d - 1) + target.red) / d
    @tone.green = (@tone.green * (d - 1) + target.green) / d
    @tone.blue = (@tone.blue * (d - 1) + target.blue) / d
    @tone.gray = (@tone.gray * (d - 1) + target.gray) / d
    @tone_duration -= 1
  end
  #--------------------------------------------------------------------------
  # * Update Fog Opacity Change
  #--------------------------------------------------------------------------
  def update_opacity_change
    return if @opacity_duration == 0
    d = @opacity_duration
    @opacity = (@opacity * (d - 1) + @opacity_target) / d
    @opacity_duration -= 1
  end
end

class Game_Fogs
  #--------------------------------------------------------------------------
  # * Object Initialization
  #--------------------------------------------------------------------------
  def initialize
    @data = []
  end
  #--------------------------------------------------------------------------
  # * Get Picture
  #--------------------------------------------------------------------------
  def [](number)
    @data[number] ||= Game_Fog.new(number)
  end
  #--------------------------------------------------------------------------
  # * Iterator
  #--------------------------------------------------------------------------
  def each
    @data.compact.each {|fog| yield fog } if block_given?
  end
end

if CLEAR_ON_TRANSFER
  class Game_Player < Game_Character
    #--------------------------------------------------------------------------
    # * Execute Player Transfer
    #--------------------------------------------------------------------------
    alias shaz_multi_fog_game_player_perform_transfer perform_transfer
    def perform_transfer
      if transfer? && @new_map_id != $game_map.map_id
        $game_map.screen.fogs.each { |fog| fog.erase }
      end
      shaz_multi_fog_game_player_perform_transfer
    end
  end
end

class Game_Interpreter
  #--------------------------------------------------------------------------
  # * Show Fog
  #--------------------------------------------------------------------------
  def show_fog(number, name, hue = 90, opacity = 64.0, blend_type = 0, zoom = 200,
    sx = 0, sy = 0, z = nil)
    screen.fogs[number].show(name, hue, opacity, blend_type, zoom, sx, sy, z)
  end
  #--------------------------------------------------------------------------
  # * Tint Fog
  #--------------------------------------------------------------------------
  def tint_fog(number, red, green, blue, gray, duration)
    screen.fogs[number].start_tone_change(Tone.new(red, green, blue, gray),
      duration)
  end
  #--------------------------------------------------------------------------
  # * Change Fog Opacity
  #--------------------------------------------------------------------------
  def fade_fog(number, opacity, duration)
    screen.fogs[number].start_opacity_change(opacity, duration)
  end
  #--------------------------------------------------------------------------
  # * Erase Fog
  #--------------------------------------------------------------------------
  def erase_fog(number)
    screen.fogs[number].erase
  end
end

class Plane_Fog < Plane
  #--------------------------------------------------------------------------
  # * Object Initialization
  #--------------------------------------------------------------------------
  def initialize(viewport, fog)
    super(viewport)
    @fog = fog
    self.z = @fog.z
    self.zoom_x = @fog.zoom / 100
    self.zoom_y = @fog.zoom / 100
    self.blend_type = @fog.blend_type
    update
  end
  #--------------------------------------------------------------------------
  # * Free
  #--------------------------------------------------------------------------
  def dispose
    bitmap.dispose if bitmap
    super
  end
  #--------------------------------------------------------------------------
  # * Frame Update
  #--------------------------------------------------------------------------
  def update
    update_bitmap
    update_move
    update_tone
    update_opacity
    update_blend
  end
  #--------------------------------------------------------------------------
  # * Update Bitmap
  #--------------------------------------------------------------------------
  def update_bitmap
    if @fog.name.empty?
      self.bitmap = nil
    else
      self.bitmap = Cache.fog(@fog.name, @fog.hue)
    end
  end
  #--------------------------------------------------------------------------
  # * Update Move
  #--------------------------------------------------------------------------
  def update_move
    self.ox = @fog.ox
    self.oy = @fog.oy
  end
  #--------------------------------------------------------------------------
  # * Update Tone
  #--------------------------------------------------------------------------
  def update_tone
    self.tone = @fog.tone
  end
  #--------------------------------------------------------------------------
  # * Update Opacity
  #--------------------------------------------------------------------------
  def update_opacity
    self.opacity = @fog.opacity
  end
  #--------------------------------------------------------------------------
  # * Update Blend
  #--------------------------------------------------------------------------
  def update_blend
    self.blend_type = @fog.blend_type
  end
end

class Spriteset_Map
  #--------------------------------------------------------------------------
  # * Object Initialization
  #--------------------------------------------------------------------------
  alias shaz_multi_fog_spriteset_map_initialize initialize
  def initialize
    shaz_multi_fog_spriteset_map_initialize
    create_fogs
    update
  end
  #--------------------------------------------------------------------------
  # * Create Fog Plane
  #--------------------------------------------------------------------------
  def create_fogs
    @fog_planes = []
  end
  #--------------------------------------------------------------------------
  # * Free
  #--------------------------------------------------------------------------
  alias shaz_multi_fog_spriteset_map_dispose dispose
  def dispose
    dispose_fogs
    shaz_multi_fog_spriteset_map_dispose
  end
  #--------------------------------------------------------------------------
  # * Free Fog Plane
  #--------------------------------------------------------------------------
  def dispose_fogs
    @fog_planes.compact.each {|fog| fog.dispose }
  end
  #--------------------------------------------------------------------------
  # * Frame Update
  #--------------------------------------------------------------------------
  alias shaz_multi_fog_spriteset_map_update update
  def update
    update_fogs
    shaz_multi_fog_spriteset_map_update
  end
  #--------------------------------------------------------------------------
  # * Update Fogs
  #--------------------------------------------------------------------------
  def update_fogs
    return if !@fog_planes
    $game_map.screen.fogs.each do |fog|
      @fog_planes[fog.number] ||= Plane_Fog.new(@viewport1, fog)
      @fog_planes[fog.number].update
    end
  end
end

if BATTLE_FOGS
  class Spriteset_Battle
    #--------------------------------------------------------------------------
    # * Object Initialization
    #--------------------------------------------------------------------------
    alias shaz_multi_fog_spriteset_battle_initialize initialize
    def initialize
      shaz_multi_fog_spriteset_battle_initialize
      create_fogs
      update
    end
    #--------------------------------------------------------------------------
    # * Create Fog Plane
    #--------------------------------------------------------------------------
    def create_fogs
      @fog_planes = []
    end
    #--------------------------------------------------------------------------
    # * Free
    #--------------------------------------------------------------------------
    alias shaz_multi_fog_spriteset_map_dispose dispose
    def dispose
      dispose_fogs
      shaz_multi_fog_spriteset_map_dispose
    end
    #--------------------------------------------------------------------------
    # * Free Fog Plane
    #--------------------------------------------------------------------------
    def dispose_fogs
      @fog_planes.compact.each {|fog| fog.dispose }
    end
    #--------------------------------------------------------------------------
    # * Frame Update
    #--------------------------------------------------------------------------
    alias shaz_multi_fog_spriteset_map_update update
    def update
      update_fogs
      shaz_multi_fog_spriteset_map_update
    end
    #--------------------------------------------------------------------------
    # * Update Fogs
    #--------------------------------------------------------------------------
    def update_fogs
      return if !@fog_planes
      $game_map.screen.update_fogs
      $game_map.screen.fogs.each do |fog|
        @fog_planes[fog.number] ||= Plane_Fog.new(@viewport1, fog)
        @fog_planes[fog.number].update
      end
    end
  end
end # BATTLE_FOGS