[froggy77]

HUD - ZL - level (LVL) & experience (XP)



I try to create a game system with points of experience and levels for my Zelda-like project.
Starlock sent me an email: "I was also planning on making an xp system and was hoping I could see your code and fiddle around with it "
So I share my work if this could be useful for others...

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SCRIPT

Here is the main script for the HUD. See in attachment.
Put this script in '../data/scripts/hud/lvl_and_xp.lua'

In this script there is a table:
self.t_xp_to_levelup = {100, 200, 300, 400, 500, 600, 700, 800}

You are level 1 and you need 100 xp  to level up.
You are level 2 and you need 200 xp  to level up.
You are level 3 and you need 300 xp  to level up.
...
You are level 8 and you need 800 xp  to level up.
Then level 9 appears and xp counters are blocked (800/800). They appears in green because I used 'small_green_digits' font that I think you have got.
Put  your own values. Obviously, it will not be 100, 200, 300 etc..
You are not limited to 8 values.

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IMPORTANT

You will have to add some lines in certain lua files. See below.
I hope I don't forget something. 

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IMAGE

Copy this image. See in attachment.

../data/sprites/hud/lvl_and_xp_icon.png

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POSITION IN THE HUD

In '../data/scripts/hud.lua' , you need declare the position of lvl and xp elements.
(-104, 16) is an example.


  ---- Create each element of the HUD.
  -- blablabla

Code: [Select]

  local lvl_and_xp_builder = require("scripts/hud/lvl_and_xp")
-- blablabla

Code: [Select]

  menu = lvl_and_xp_builder:new(game)
  menu:set_dst_position(-104, 16)
  hud.elements[#hud.elements + 1] = menu
-- blablabla

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SAVEGAME FILE

In "../data/scripts/game_manager.lua", and more precisely in the "function game_manager:create(file)", we have to declare two values for a new savegame file. Also add 'current_level = 0'  and 'current_xp = 0' in your existing savegame files.

--  if not exists then
    ---- This is a new savegame file.
   -- blablabla

Code: [Select]

game:set_value("current_level", 0)
game:set_value("current_xp", 0)
--  end
-- blablabla

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FUNCTIONS TO ADD, SET or GET XP and LEVEL

In '../data/scripts/quest_manager.lua', because I think it is practical to add or set or  get xp and level of our hero, I added some functions.
All these functions are not necessaries, but they are very useful in debug console to test.
hero:set_level(3) is equal to game:set_value("current_level", 3)
hero:add_level(1) so  'current_level = 4' in your 'saveX.dat' if you save the game.
hero:get_level() is equal to game:get_value("current_level")
hero:set_xp(100)    is equal to  game:set_value("current_xp", 100)
hero:add_xp(10)   so  'current_xp = 110' in your 'saveX.dat' if you save the game. hero:add_xp(number) is the most useful for enemies.
hero:get_xp()  is equal to  game:get_value("current_xp")

Code: (lua) [Select]

-- Initializes some behavior of our hero.
local function initialize_hero()

  local hero_meta = sol.main.get_metatable("hero")
 
  -- ZL --  Functions for levels of our hero
  function hero_meta:set_level(lvl)

    if type(lvl) == "number" then
local game = self:get_game()
game:set_value("current_level", lvl)
else
        print("Error in hero:set_level(lvl), lvl should be a number.")
    end
  end
  function hero_meta:add_level(lvl)

    if type(lvl) == "number" then
local game = self:get_game()
local current_level = game:get_value("current_level")
game:set_value("current_level", current_level + lvl)
else
        print("Error in hero:add_level(lvl), lvl should be a number.")
end
  end
  function hero_meta:get_level()

local game = self:get_game()
local current_level = game:get_value("current_level")
return current_level
  end
  -- ZL --  Functions for experience points of our hero
  function hero_meta:set_xp(xp)

    if type(xp) == "number" then
local game = self:get_game()
game:set_value("current_xp", xp)
else
        print("Error in hero:set_xp(xp), xp should be a number.")
    end
  end
  function hero_meta:add_xp(xp)

    if type(xp) == "number" then
local game = self:get_game()
local current_xp = game:get_value("current_xp")
game:set_value("current_xp", current_xp + xp)
else
        print("Error in hero:add_xp(xp), xp should be a number.")
end
  end
  function hero_meta:get_xp()

local game = self:get_game()
local current_xp = game:get_value("current_xp")
return current_xp
  end

end


Edit: Sorry, don't forget to  initialize_hero() !!!

Code: (Lua) [Select]

function quest_manager:initialize_quest()
 
  -- blablabla
  initialize_hero()
  -- blablabla
 
end
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ENEMIES

In your scripts for enemies where you have declared their behavior  (e.g  ../data/enemies/lib/slime_behavior.lua),
just add a variable named for example "properties.xp" in your 'function behavior:create(enemy, properties)'. I don't know, but the name of your function is perhaps different.

In my example, I decided to define xp according to life, damage and speed of the enemy.

Code: [Select]

properties.xp = properties.xp or (properties.life * properties.damage * properties.normal_speed)
In this example, I added xp in the 'function enemy:on_dying()', I think it is logical, but you can do differently:

  function enemy:on_dying()
 

Code: [Select]

local hero = enemy:get_map():get_entity("hero")
hero:add_xp(properties.xp)  end

[MetalZelda]

Fantastic, absolutely superb, nice work.

This should be pinned if possible.

[froggy77]

Thanks Metalzelda 
If someone has tested this xp and level system, please tell me if my tutorial is clear and if it works correctly in your game.

I will update the first post as I just do it for initialize_hero().

[Starlock]

Thanks frog! I'll test it out on my game as soon as I get the chance.

[froggy77]

Sorry for the necropost. It is not my fault; it's Miguelink 64's fault  and its topic named "Simple Leveling up system"

Yeury already sent me an email in 2017 telling me that my script was not up to date for the part "quest_manager.lua".
I did not understand thinking that "quest_manager.lua" was the standard in Solarus scripts. I was completely wrong and I realize that I should review the script, but I would have to go back to the lua.I had a little level to do something nice enough, but I'm rusty today. I do not understand anymore my script (or at least some parts) and I do not even know or put the content of "quest_manager.lua" to be at the current standard of Solarus scripts. I would like a little help.
Thanks in advance.

[froggy77]

I close the topic. There is an updated version by Kamigousu here.