[RGSS3] Galv's Cam Control (edited)

#------------------------------------------------------------------------------#
#  Galv's Cam Control
#------------------------------------------------------------------------------#
#  For: RPGMAKER VX ACE
#  Version 1.4
#  edited by LiTTleDRAgo
#------------------------------------------------------------------------------#
#  2013-03-18 - Version 1.4 - fixed a bug where it crashed if you didn't turn
#                           - off following an event when transferring to a map
#                           - without that event.
#  2013-03-18 - Version 1.3 - fixed a bug with parallax motion stopping
#  2013-03-04 - Version 1.2 - re-written script to scroll to targets
#  2012-10-24 - Version 1.1 - updated alias naming for compatability
#  2012-10-20 - Version 1.0 - release
#------------------------------------------------------------------------------#
#  This script allows some control over where the camera is through use of
#  script calls. You can fix the camera to a location on the map or follow an
#  event's movements.
#------------------------------------------------------------------------------#
#  SCRIPT CALLS:
#------------------------------------------------------------------------------#
#
#  cam_follow(event_id,speed)   # Camera follows event instead of player
#  cam_center(speed)            # Moves camera back to player
#  cam_set(x,y,speed)      # Position the camera centered on x, y coordinates
#
# # NOTE: speed can be 1 to 6 or you can leave it out of the script call to
#         default to 6. If you want to instantly snap the camera without it
#         scrolling, make speed 0
#
#------------------------------------------------------------------------------#
#  EXAMPLES:
#  cam_set(10,5)         # Moves camera to map co-ordinates x 10, y5 at speed 6
#  cam_set(10,5,2)       # Moves camera to map co-ordinates x 10, y5 at speed 2
#  cam_follow(4)         # Moves camera to event 4's location and follows it.
#  cam_follow(4,0)       # SNAPS camera to event 4's location and follows it.
#  cam_center            # Moves camera to player at speed 6
#  cam_center(0)         # Snaps camera to player instantly
#------------------------------------------------------------------------------#
# NO OPTIONS FOR YOU TO EDIT. SORRY.
#------------------------------------------------------------------------------#

$imported = {} if $imported.nil?
$imported["Camera_Control"] = true

class Game_Map
  attr_accessor :cam_target

  alias_method :galv_cam_control_gm_setup, :setup
  def setup(*args)
    @cam_target = 0
    galv_cam_control_gm_setup(*args)
    @scroll_blocked = false
  end

  unless $imported[:drg_diagonal_scroll]
    @@scroll = method_defined?(:do_scroll) ? :do_scroll : :update
    alias_method :update_scrolling_straight, :"#{@@scroll}"

    define_method(:"#{@@scroll}") do |*args|
      update_scrolling_diagonal || 0 && update_scrolling_straight(*args)
    end

    def update_scrolling_diagonal
      if scrolling?
        distance = 2 ** @scroll_speed
        distance = scroll_distance if defined?(scroll_distance)
        case @scroll_direction
        when 1 then [scroll_down(distance), scroll_left(distance) ]
        when 3 then [scroll_down(distance), scroll_right(distance)]
        when 7 then [scroll_up(distance),   scroll_left(distance) ]
        when 9 then [scroll_up(distance),   scroll_right(distance)]
        end
      end
    end
  end

  def scroll_to_target(x,y,speed)
    x1, y1, dir = @display_x.to_i, @display_y.to_i, 0
    dir = 1 if dir == 0 && y1 < y && x1 > x && scroll_can_move?(2) && scroll_can_move?(4)
    dir = 7 if dir == 0 && y1 > y && x1 > x && scroll_can_move?(8) && scroll_can_move?(4)
    dir = 9 if dir == 0 && y1 > y && x1 < x && scroll_can_move?(8) && scroll_can_move?(6)
    dir = 3 if dir == 0 && y1 < y && x1 < x && scroll_can_move?(2) && scroll_can_move?(6)
    dir = 2 if dir == 0 && y1 < y && scroll_can_move?(2)
    dir = 8 if dir == 0 && y1 > y && scroll_can_move?(8)
    dir = 6 if dir == 0 && x1 < x && scroll_can_move?(6)
    dir = 4 if dir == 0 && x1 > x && scroll_can_move?(4)
    start_scroll(dir, 1, speed) if dir > 0
    @scroll_blocked = dir == 0
    Fiber.yield while scrolling?
  end

  def cannot_scroll?
    @scroll_blocked == true
  end

  def scroll_can_move?(dir)
    case dir
    when 2 then (@display_y % @map.height) < height - (Graphics.height / 32)
    when 4 then (@display_x % @map.width)  > 0
    when 6 then (@display_x % @map.width)  < width  - (Graphics.width  / 32)
    when 8 then (@display_y % @map.height) > 0
    end
  end

  def set_event_display_pos(x, y)
    x = [0, [x, width  - screen_tile_x].min].max unless loop_horizontal?
    y = [0, [y, height - screen_tile_y].min].max unless loop_vertical?
    @display_x = (x + width) % width
    @display_y = (y + height) % height
  end

end # Game_Map

class Game_Player < Game_Character

  alias_method :galv_cam_control_gp_update, :update
  alias_method :galv_cam_control_gp_update_scroll, :update_scroll

  def update(*args)
    if (target = $game_map.cam_target).is_a?(Integer) && target > 0
      e = $game_map.interpreter.get_character(t)
    elsif target.is_a?(Game_Character)
      e = target
    end
    e && $game_map.set_event_display_pos(e.real_x-center_x, e.real_y-center_y)
    galv_cam_control_gp_update(*args)
  end

  def update_scroll(*args)
    return if ($game_map.cam_target ||= 0) != 0
    galv_cam_control_gp_update_scroll(*args)
  end
end # Game_Player < Game_Character

class Game_Interpreter

  def cam_center(speed = 6)
    cam_set($game_player.x, $game_player.y, speed)
    $game_map.cam_target = 0
  end

  def cam_set(x,y,speed = 6)
    $game_map.cam_target = -1
    _x = (x - $game_player.center_x).round
    _y = (y - $game_player.center_y).round
    speed > 0 && scroll_to_target(x,y,speed)
    $game_map.set_display_pos(_x, _y)
  end

  def scroll_to_target(x,y,speed)
    _x = (x - $game_player.center_x).round
    _y = (y - $game_player.center_y).round
    loop do
      $game_map.scroll_to_target(_x, _y, speed)
      finish = $game_map.display_x == _x && $game_map.display_y == _y
      break if finish || $game_map.cannot_scroll?
    end
  end

  def scroll_to_event(id,speed)
    char = id.is_a?(Game_Character) ? id : get_character(id)
    char && scroll_to_target(char.x,char.y,speed)
  end

  def cam_follow(event_id, speed = 6)
    $game_map.cam_target = -1
    char = event_id.is_a?(Game_Character) ? event_id : get_character(event_id)
    char && speed > 0 && scroll_to_event(char,speed)
    char && ($game_map.cam_target = char)
  end
end # Game_Interpreter