Moving Screen help, like an overhead scrolling shooter Options

[Claytonic]

I am wondering how to make a minigame like an overhead-scrolling-shooter where the screen moves at a slow pace on a set route while the player can move about freely within that space. I won't actually be using a plane, shooting down other ships.... What I think is hard to do is to keep the player trapped within the space shown on screen. This might be possible through eventing only, but may be easier with scripting? Can someone please help make this possible? (Or show me where someone has already made this?)

This post has been edited by Claytonic: Jan 12 2013, 03:44 PM

[Jens of Zanicuud]

You need some scripts to do that... Events and Common Events can't handle this efficiently.
Are you planning to scroll it like an Aero Fighter game (from south to north) or more like Gradius (from left to right)?

For a Gradius-like effect, you could try this one...

CODE

#===============================================================================
# ** Jens of Zanicuud horizontal scroll engine v 0.8
# - free use, just credit
# - free customization, just PM me the modified version
# - you can find me at www.rpgrevolution.com
#===============================================================================
# This script will confine the player between the screen's limits by setting
# a certain switch to ON (see next lines for a more precise description).
# This script could have some compatibility problem, since when the switch
# is active, it overruns the update method of the Game_Player class.
# Use it carefully and ask for troubleshooting anytime!
# NOTE: for now, it works ONLY with horizontal scrolling from LEFT to RIGHT!
#===============================================================================

#--------------------------------------------------------------------------
# ** Game_Player
#--------------------------------------------------------------------------
class Game_Player < Game_Character
  #--------------------------------------------------------------------------
  # * Constants
  #--------------------------------------------------------------------------
  #id of the switch which triggers the scroll game (e.g. 1 means you have to
  #set the Switch[0001] to ON.
  Scroll_game_switch = 1
  #--------------------------------------------------------------------------
  # * Aliases
  #--------------------------------------------------------------------------
  alias scroll_system_center center
  alias scroll_update        update
  alias scroll_moving        moving?
  #--------------------------------------------------------------------------
  # * Center camera on the player
  #--------------------------------------------------------------------------
  def center(x, y)
    if !$game_switches[Scroll_game_switch]
      scroll_system_center(x,y)
    end
  end
  #--------------------------------------------------------------------------
  # * Scroll_Moving?
  #--------------------------------------------------------------------------
  def scroll_moving?
    if @real_x  <= $game_map.display_x
      if @real_y != @y * 128
        return true
      else
        return false
      end
    elsif @real_x  >= $game_map.display_x + 640*4 - 128
      if @real_y != @y * 128
        return true
      else
        return false
      end
    else
      return moving?
    end
  end
  #--------------------------------------------------------------------------
  # * Update
  #--------------------------------------------------------------------------
  def update
    if $game_switches[Scroll_game_switch]
    last_moving = moving?
    unless scroll_moving? or $game_system.map_interpreter.running? or
           @move_route_forcing or $game_temp.message_window_showing
      case Input.dir4
      when 2
        move_down
      when 4
        move_left
      when 6
        move_right
      when 8
        move_up
      end
      update_move
    end
    last_real_x = @real_x
    last_real_y = @real_y
    super
    unless moving?
      if last_moving
        result = check_event_trigger_here([1,2])
        if result == false
          unless $DEBUG and Input.press?(Input::CTRL)
            if @encounter_count > 0
              @encounter_count -= 1
            end
          end
        end
      end
      if Input.trigger?(Input::C)
        check_event_trigger_here([0])
        check_event_trigger_there([0,1,2])
        end
      end
  else
    scroll_update
  end
end
  #--------------------------------------------------------------------------
  # * Update Move
  #--------------------------------------------------------------------------
  def update_move
   if $game_switches[Scroll_game_switch]
     screen = [$game_map.display_x,
               $game_map.display_y,
               $game_map.display_x + 640*4 - 128,
               $game_map.display_y + 480*4 - 128]
     distance = 2 ** @move_speed
     if @y * 128 > @real_y
       @real_y = [[@real_y + distance, @y * 128].min, screen[3]].min
       @real_x = [[screen[0], @real_x].max,screen[2]].min
       if @real_y  == screen[3]
         @y = @real_y / 128
       end
     end
     if @x * 128 < @real_x
       @real_x = [[@real_x - distance, @x * 128].max, screen[0]].max
       @real_y = [[screen[1], @real_y].max,screen[3]].min
       if @real_x  == screen[0]
         @x = @real_x / 128
       end
     end
     if @x * 128 > @real_x
       @real_x = [[@real_x + distance, @x * 128].min, screen[2]].min
       @real_y = [[screen[1], @real_y].max,screen[3]].min
       if @real_x  == screen[2]
         @x = @real_x / 128
       end
     end
     if @y * 128 < @real_y
       @real_y = [[@real_y - distance, @y * 128].max, screen[1]].max
       @real_x = [[screen[0], @real_x].max,screen[2]].min
       if @real_y  == screen[1]
         @y = @real_y / 128
       end
     end
     if @walk_anime
      @anime_count += 1.5
     elsif @step_anime
      @anime_count += 1
     end
   else
     super
   end
end
  #--------------------------------------------------------------------------
  # * Update Stop
  #--------------------------------------------------------------------------
  def update_stop
    super
    if $game_switches[Scroll_game_switch]
      screen = [$game_map.display_x,
               $game_map.display_y,
               $game_map.display_x + 640*4 - 128,
               $game_map.display_y + 480*4 - 128]
      @real_x = [[screen[0], @real_x].max,screen[2]].min
      @real_y = [[screen[1], @real_y].max,screen[3]].min
    end
  end
end

Jens

[Claytonic]

Well my plan is to use it in an adventure game, so I want enough control to move the screen on a set path, it could be up, down, left or right, changing direction as it follows the path of the dungeon. Sorry that I know so little scripting myself....

[Jens of Zanicuud]

Uhm... okay. I've got it. Of course, this would be more difficult to do, but I hope not too much.
If I'll be able to work out something, I'll PM you.

Jens

[Claytonic]

You need some scripts to do that... Events and Common Events can't handle this efficiently.
Are you planning to scroll it like an Aero Fighter game (from south to north) or more like Gradius (from left to right)?

For a Gradius-like effect, you could try this one...

CODE

#===============================================================================
# ** Jens of Zanicuud horizontal scroll engine v 0.8
# - free use, just credit
# - free customization, just PM me the modified version
# - you can find me at www.rpgrevolution.com
#===============================================================================
# This script will confine the player between the screen's limits by setting
# a certain switch to ON (see next lines for a more precise description).
# This script could have some compatibility problem, since when the switch
# is active, it overruns the update method of the Game_Player class.
# Use it carefully and ask for troubleshooting anytime!
# NOTE: for now, it works ONLY with horizontal scrolling from LEFT to RIGHT!
#===============================================================================

#--------------------------------------------------------------------------
# ** Game_Player
#--------------------------------------------------------------------------
class Game_Player < Game_Character
  #--------------------------------------------------------------------------
  # * Constants
  #--------------------------------------------------------------------------
  #id of the switch which triggers the scroll game (e.g. 1 means you have to
  #set the Switch[0001] to ON.
  Scroll_game_switch = 1
  #--------------------------------------------------------------------------
  # * Aliases
  #--------------------------------------------------------------------------
  alias scroll_system_center center
  alias scroll_update        update
  alias scroll_moving        moving?
  #--------------------------------------------------------------------------
  # * Center camera on the player
  #--------------------------------------------------------------------------
  def center(x, y)
    if !$game_switches[Scroll_game_switch]
      scroll_system_center(x,y)
    end
  end
  #--------------------------------------------------------------------------
  # * Scroll_Moving?
  #--------------------------------------------------------------------------
  def scroll_moving?
    if @real_x  <= $game_map.display_x
      if @real_y != @y * 128
        return true
      else
        return false
      end
    elsif @real_x  >= $game_map.display_x + 640*4 - 128
      if @real_y != @y * 128
        return true
      else
        return false
      end
    else
      return moving?
    end
  end
  #--------------------------------------------------------------------------
  # * Update
  #--------------------------------------------------------------------------
  def update
    if $game_switches[Scroll_game_switch]
    last_moving = moving?
    unless scroll_moving? or $game_system.map_interpreter.running? or
           @move_route_forcing or $game_temp.message_window_showing
      case Input.dir4
      when 2
        move_down
      when 4
        move_left
      when 6
        move_right
      when 8
        move_up
      end
      update_move
    end
    last_real_x = @real_x
    last_real_y = @real_y
    super
    unless moving?
      if last_moving
        result = check_event_trigger_here([1,2])
        if result == false
          unless $DEBUG and Input.press?(Input::CTRL)
            if @encounter_count > 0
              @encounter_count -= 1
            end
          end
        end
      end
      if Input.trigger?(Input::C)
        check_event_trigger_here([0])
        check_event_trigger_there([0,1,2])
        end
      end
  else
    scroll_update
  end
end
  #--------------------------------------------------------------------------
  # * Update Move
  #--------------------------------------------------------------------------
  def update_move
   if $game_switches[Scroll_game_switch]
     screen = [$game_map.display_x,
               $game_map.display_y,
               $game_map.display_x + 640*4 - 128,
               $game_map.display_y + 480*4 - 128]
     distance = 2 ** @move_speed
     if @y * 128 > @real_y
       @real_y = [[@real_y + distance, @y * 128].min, screen[3]].min
       @real_x = [[screen[0], @real_x].max,screen[2]].min
       if @real_y  == screen[3]
         @y = @real_y / 128
       end
     end
     if @x * 128 < @real_x
       @real_x = [[@real_x - distance, @x * 128].max, screen[0]].max
       @real_y = [[screen[1], @real_y].max,screen[3]].min
       if @real_x  == screen[0]
         @x = @real_x / 128
       end
     end
     if @x * 128 > @real_x
       @real_x = [[@real_x + distance, @x * 128].min, screen[2]].min
       @real_y = [[screen[1], @real_y].max,screen[3]].min
       if @real_x  == screen[2]
         @x = @real_x / 128
       end
     end
     if @y * 128 < @real_y
       @real_y = [[@real_y - distance, @y * 128].max, screen[1]].max
       @real_x = [[screen[0], @real_x].max,screen[2]].min
       if @real_y  == screen[1]
         @y = @real_y / 128
       end
     end
     if @walk_anime
      @anime_count += 1.5
     elsif @step_anime
      @anime_count += 1
     end
   else
     super
   end
end
  #--------------------------------------------------------------------------
  # * Update Stop
  #--------------------------------------------------------------------------
  def update_stop
    super
    if $game_switches[Scroll_game_switch]
      screen = [$game_map.display_x,
               $game_map.display_y,
               $game_map.display_x + 640*4 - 128,
               $game_map.display_y + 480*4 - 128]
      @real_x = [[screen[0], @real_x].max,screen[2]].min
      @real_y = [[screen[1], @real_y].max,screen[3]].min
    end
  end
end

Jens

I tried loking through the code, again I'm not nuch of a scripter, and I couldn't identify the exact spot where the code controls the screen movement, but...would it be possible to change the moving switch to a variable and then change the code to be just like how it is but with up, down, left and right sections for what the variable is set to?
How much different is the up-scrolling code versus the right-scrolling code?

[Jens of Zanicuud]

You need some scripts to do that... Events and Common Events can't handle this efficiently.
Are you planning to scroll it like an Aero Fighter game (from south to north) or more like Gradius (from left to right)?

For a Gradius-like effect, you could try this one...

CODE

#===============================================================================
# ** Jens of Zanicuud horizontal scroll engine v 0.8
# - free use, just credit
# - free customization, just PM me the modified version
# - you can find me at www.rpgrevolution.com
#===============================================================================
# This script will confine the player between the screen's limits by setting
# a certain switch to ON (see next lines for a more precise description).
# This script could have some compatibility problem, since when the switch
# is active, it overruns the update method of the Game_Player class.
# Use it carefully and ask for troubleshooting anytime!
# NOTE: for now, it works ONLY with horizontal scrolling from LEFT to RIGHT!
#===============================================================================

#--------------------------------------------------------------------------
# ** Game_Player
#--------------------------------------------------------------------------
class Game_Player < Game_Character
  #--------------------------------------------------------------------------
  # * Constants
  #--------------------------------------------------------------------------
  #id of the switch which triggers the scroll game (e.g. 1 means you have to
  #set the Switch[0001] to ON.
  Scroll_game_switch = 1
  #--------------------------------------------------------------------------
  # * Aliases
  #--------------------------------------------------------------------------
  alias scroll_system_center center
  alias scroll_update        update
  alias scroll_moving        moving?
  #--------------------------------------------------------------------------
  # * Center camera on the player
  #--------------------------------------------------------------------------
  def center(x, y)
    if !$game_switches[Scroll_game_switch]
      scroll_system_center(x,y)
    end
  end
  #--------------------------------------------------------------------------
  # * Scroll_Moving?
  #--------------------------------------------------------------------------
  def scroll_moving?
    if @real_x  <= $game_map.display_x
      if @real_y != @y * 128
        return true
      else
        return false
      end
    elsif @real_x  >= $game_map.display_x + 640*4 - 128
      if @real_y != @y * 128
        return true
      else
        return false
      end
    else
      return moving?
    end
  end
  #--------------------------------------------------------------------------
  # * Update
  #--------------------------------------------------------------------------
  def update
    if $game_switches[Scroll_game_switch]
    last_moving = moving?
    unless scroll_moving? or $game_system.map_interpreter.running? or
           @move_route_forcing or $game_temp.message_window_showing
      case Input.dir4
      when 2
        move_down
      when 4
        move_left
      when 6
        move_right
      when 8
        move_up
      end
      update_move
    end
    last_real_x = @real_x
    last_real_y = @real_y
    super
    unless moving?
      if last_moving
        result = check_event_trigger_here([1,2])
        if result == false
          unless $DEBUG and Input.press?(Input::CTRL)
            if @encounter_count > 0
              @encounter_count -= 1
            end
          end
        end
      end
      if Input.trigger?(Input::C)
        check_event_trigger_here([0])
        check_event_trigger_there([0,1,2])
        end
      end
  else
    scroll_update
  end
end
  #--------------------------------------------------------------------------
  # * Update Move
  #--------------------------------------------------------------------------
  def update_move
   if $game_switches[Scroll_game_switch]
     screen = [$game_map.display_x,
               $game_map.display_y,
               $game_map.display_x + 640*4 - 128,
               $game_map.display_y + 480*4 - 128]
     distance = 2 ** @move_speed
     if @y * 128 > @real_y
       @real_y = [[@real_y + distance, @y * 128].min, screen[3]].min
       @real_x = [[screen[0], @real_x].max,screen[2]].min
       if @real_y  == screen[3]
         @y = @real_y / 128
       end
     end
     if @x * 128 < @real_x
       @real_x = [[@real_x - distance, @x * 128].max, screen[0]].max
       @real_y = [[screen[1], @real_y].max,screen[3]].min
       if @real_x  == screen[0]
         @x = @real_x / 128
       end
     end
     if @x * 128 > @real_x
       @real_x = [[@real_x + distance, @x * 128].min, screen[2]].min
       @real_y = [[screen[1], @real_y].max,screen[3]].min
       if @real_x  == screen[2]
         @x = @real_x / 128
       end
     end
     if @y * 128 < @real_y
       @real_y = [[@real_y - distance, @y * 128].max, screen[1]].max
       @real_x = [[screen[0], @real_x].max,screen[2]].min
       if @real_y  == screen[1]
         @y = @real_y / 128
       end
     end
     if @walk_anime
      @anime_count += 1.5
     elsif @step_anime
      @anime_count += 1
     end
   else
     super
   end
end
  #--------------------------------------------------------------------------
  # * Update Stop
  #--------------------------------------------------------------------------
  def update_stop
    super
    if $game_switches[Scroll_game_switch]
      screen = [$game_map.display_x,
               $game_map.display_y,
               $game_map.display_x + 640*4 - 128,
               $game_map.display_y + 480*4 - 128]
      @real_x = [[screen[0], @real_x].max,screen[2]].min
      @real_y = [[screen[1], @real_y].max,screen[3]].min
    end
  end
end

Jens

I tried loking through the code, again I'm not nuch of a scripter, and I couldn't identify the exact spot where the code controls the screen movement, but...would it be possible to change the moving switch to a variable and then change the code to be just like how it is but with up, down, left and right sections for what the variable is set to?
How much different is the up-scrolling code versus the right-scrolling code?

The Up-Scrolling isn't too much difficult to implement, but I'm in a bad period and I can't script it right now.
If you can wait till March, I'll give it a look.

Jens

[Claytonic]

sure thing, that's cool. no rush

Oh yeah, and of sourse I would like it to be compatible with an action battle system script. Any one really, Blizz-ABS, XAS, etc. I hope that's not an issue.

This post has been edited by Claytonic: Feb 17 2013, 11:35 AM

[Redd]

I saw a script a while ago that would center the camera on the player at all times... like a Pokemon game. I can't seem to find it right now, but is that what you are asking for?

[Claytonic]

I saw a script a while ago that would center the camera on the player at all times... like a Pokemon game. I can't seem to find it right now, but is that what you are asking for?

Actually, I want sort of the opposite of that. I want the screen to slowly move on its own while the player is restricted to moving around inside the "on-screen" area, so the camera would have to not follow the player at all. Instead, the player is forced to follow the camera.

[Redd]

Like the scrolling levels in Super Mario Bros., just upwards instead?

[Claytonic]

Like the scrolling levels in Super Mario Bros., just upwards instead?

Yes, rather, over-head instead. Changing the direction at a point in the dungeon would be cool too. I swear I've played a game that does this but I can't think of it....

[Jens of Zanicuud]

Like the scrolling levels in Super Mario Bros., just upwards instead?

Yes, rather, over-head instead. Changing the direction at a point in the dungeon would be cool too. I swear I've played a game that does this but I can't think of it....

Okay, I've got the problem.
You need a script which could bind the player (i.e. the player is moved by the screen bounds, if it remains still - right?) but there are a couple problems. First off, RMXP implements a tile system which actually greatly reduces free movement. In practice, if you tell the program "hey, I want you to force my lil' player to move by three pixels" this won't work unless you modify the whole system. Second, I need some more detail.
What kind of game is this supposed to be? A platform or a sort of Gradius-side-scroller?
I'll see what I can do.

Jens

[Claytonic]

Okay, upon reviewing my game library, I could not find an example of what I visualized....
What this game is going to be is a sort of overhead action game. I'm starting to think binding the player to the screen will not be necessary(close walls and other things can do that). What I want is to be able to control a moving camera and not have it center on the player while he is moving around the level (this is to keep the player moving through the level at a specified pace, not going back for anything he misses).

[Jens of Zanicuud]

Okay, upon reviewing my game library, I could not find an example of what I visualized....
What this game is going to be is a sort of overhead action game. I'm starting to think binding the player to the screen will not be necessary(close walls and other things can do that). What I want is to be able to control a moving camera and not have it center on the player while he is moving around the level (this is to keep the player moving through the level at a specified pace, not going back for anything he misses).

Do you need a "every-direction-screen-movement" or is there a precise direction the game is developed to?

Jens

[Claytonic]

Do you need a "every-direction-screen-movement" or is there a precise direction the game is developed to?

Jens

Yes, I want it in every direction.

[Jens of Zanicuud]

Do you need a "every-direction-screen-movement" or is there a precise direction the game is developed to?

Jens

Yes, I want it in every direction.

Okay, let's put it fair and square: the script isn't the most easy, since RMXP tilesets structure.
I need a couple more pieces of information:
>first of all, I need to know how the game camera is placed: is it a classic RPG (seen from above, as RMXP standard) or a platform game like any SuperMario? In the latter case, I could get rid of the tileset structure and design another system;
>second, in case the game is seen from above, should I proceed anyway and get rid of the tileset structure (free movement , instead of that 32 pixels move - some passability issues)?
>third, has the player to be "dragged" from the screen? (i.e. if the charcter is placed on the left side and the screen is moving right, should the screen drag the player with it?)
Sorry for the huge number of questions, but I can't properly design it without these pieces of information

Jens

[Claytonic]

Okay, let's put it fair and square: the script isn't the most easy, since RMXP tilesets structure.
I need a couple more pieces of information:
>first of all, I need to know how the game camera is placed: is it a classic RPG (seen from above, as RMXP standard) or a platform game like any SuperMario? In the latter case, I could get rid of the tileset structure and design another system;
>second, in case the game is seen from above, should I proceed anyway and get rid of the tileset structure (free movement , instead of that 32 pixels move - some passability issues)?
>third, has the player to be "dragged" from the screen? (i.e. if the charcter is placed on the left side and the screen is moving right, should the screen drag the player with it?)
Sorry for the huge number of questions, but I can't properly design it without these pieces of information

Jens

Not at all, I'm asking for help so it is best that you know what I want help with.
1) It will be overhead, seen from above, classic rpg style.
2) Free movement would be best so feel free to get rid of the tileset structure.
3) Dragging the character along is not necessary, but not bad if possible.
Also, I want to be able to disable/enable it per dungeon (the screen moving part, keep the free movement at all times).

[Jens of Zanicuud]

1) Okay, this is good;
2) Crap, this is bad Passability issues ahead! (I'll see what I can do)
3) What if the screen doesn't drag the player? Is the player supposed to follow the screen, to die when the screen overcomes him, or simply the screen is supposed to stop if the player is on one of their sides?

I'll begin working on it once I'll be supplied with this last info

Jens

[Claytonic]

Um, if you can make it so the player is dragged to be kept on screen, that would be amazing.
Again, I don't know the technical problems you run into when scripting so I don't know which is easier, but another idea for back-up is if the player goes off screen then they are teleported to the center of the screen (maybe after being gone for three seconds?). I don't want the screen to stop and wait for the player.

This post has been edited by Claytonic: Mar 30 2013, 02:25 PM

[Jens of Zanicuud]

Um, if you can make it so the player is dragged to be kept on screen, that would be amazing.
Again, I don't know the technical problems you run into when scripting so I don't know which is easier, but another idea for back-up is if the player goes off screen then they are teleported to the center of the screen (maybe after being gone for three seconds?). I don't want the screen to stop and wait for the player.

Alright
I'll see what I can do.

Jens