base class

MoKaLux

I would need your help, please.

I don't know how to create a base class for my enemies.

For example I have one enemy class:

Enemy01 = Core.class(Sprite)   function Enemy01:init(xname, xposx, xposy) -- settings self.name = xname self.x = xposx self.y = xposy self.vx = 0 self.vy = 0 self.flip = 1 self.isonfloor = false self.isattacking = false self.lives = 3 self.accel = 500 self.friction = 150 self.maxspeed = 150 self.jumpspeed = GRAVITY / 2 end   function Enemy01:createAnim(xanimname, xstart, xfinish, xanimslist) self.anims[xanimname] = {} for i = xstart, xfinish do self.anims[xanimname][#self.anims[xanimname] + 1] = xanimslist[i] end end

I have different enemies which would have different parameters value.
How can I make a base class which my enemies would inherit (variables and functions).

I have searched on the forum but I don't know how to handle this.

Thank you in advance for your time.

Apollo14

EnemyAdvanced = Core.class(Enemy01)   function EnemyAdvanced:init()   end

hgy29

Note that when using Core.class() to create a sub-class, the arguments sent to your new/init function will be used to call the superclass init too, which can have undesired effects. To handle this, I use my own Core.class call:

Core.classArgs=function (p,a) local c=Core.class(p) c.__new = function(...) local b = getmetatable(c) local s1 = b.__new(a(...)) setmetatable(s1, c) local init = rawget(c, "init") if type(init) == "function" then init(s1, ...) end return s1 end return c end

It takes a second argument, which is a function that will return the arguments intended for the superclass based on the new class constructor arguments. Example:

-- Define a new class to make a 50x50 pixel. Argument is the plain color Pixel50=Core.classArgs(Pixel,function(color) return color,1,50,50 end)   --Use it stage:addChild(Pixel50.new(0xFF0000)) -- Create a 50x50 red pixel

I was thinking about enhancing gideros Core.class to do the same (if second arg is present), what do you think ?

MoKaLux

thank you guys for the answers.

@Apollo14 I knew this bit Enemy02 = Core.class(Enemy) but then what do I put in the init()? only the values that are going to change? For example:

Enemy02 = Core.class(Enemy) function Enemy02:init() self.vx = 30 self:createAnim("walk", 1, 6, myanims_list) end

Ok, I should experiment more. Right now I do it the "easy" way but I feel like my code isn't nice.

@hgy29 I have read on the forum about Core.class and how it is implemented by @atilim . That is a little bit too advanced for me so I cannot tell what should be done.

antix

With my games I haven't had to create subclasses, I just have a class for enemy which gets passed options that are overwritten on init() to make it different to other enemies. In fact all of my GUI objects use the same method.

Enemy = Core.class(Bitmap)   function Enemy:init(texture, options) -- default options self.position = {x = 0, y = 0}, self.velocity = {x = 0, y = 0}, self.alive = true, self.type = 'MUTANT', self.canBeClicked = true   -- copy any supplied options if options then for key, value in pairs(options) do self[key]= value end end   -- etc, etc end

Not the greatest code in the world maybe, but it works.

MoKaLux

@antix excellent, I am ending up doing something similar, maybe not the best way but it's easier for me! Thank you for sharing.