Forewords

Currenltly, the only mandatory key is ptype which takes either plot or polar. There is no mandatory value for any sections other than that, however the func and funcx values are very sensitive (because they are parsed using a very simple load(<code string>) function). You can also remove the ptype and manually call the functions in the TIC() functions. Also, use ... as the variable when defining functions!

  {
     func   =  "1"        -- [string] <compilable to function>
     funcx  =  "..."      -- [string] <compilable to function>
     start  = -100        -- [number]
     finish =  100        -- [number]
     prec   = 0.1         -- [number]
     color  =  2          -- [number]
     label  =  "function" -- [string]
     ptype  =  plot       -- <function>: plot, polar. // planned: plot3d, polar3d, plotiz
  }
A typical function is like this:

For a polar() function, consider func as a polar function, for a normal plot(), if you only define func, the code behaves as a normal function on the 2d plane (y=func(x)). Changing funcx results in a curve of lambda=(funcx(t),func(t)).

There is currently no support for adding custom/several function during running the cart, but you can add your custom functions to "Add functions manually" section (or in the source code) and navigate through the function/pages with Up/Down arrow keys.

Update 2024-11-09

I have learned that there are legit ways like using lsp-lua to document code. It is also very important to note that this is a very experimental work and not ready for day to day use, but I'm aiming to make it versatile enough to replace online services I use. This is UNSTABLE PRE-ALPHA I guess. The code license is GPL-3.0, the document license is CC BY-SA 4.0.

Metadata

This is still undecided!

  -- title:    Plotter
  -- author    Behnam (Wired Unwell)
  -- desc:     A simple experimental plotter for TIC-80
  -- site:     wired_unwell.codeberg.page
  -- license:  GPL-3.0
  -- version:  0.1
  -- script:   lua
  -- input:    keyboard

Initialize variables and basic functions 

  o={x=120,
     y=68,
     z=10}

  fnsi=1

  sin=math.sin
  cos=math.cos
  log=math.log
  pi=math.pi

2D Plane 

  function plot(ptable)
     local ll = ptable.start or -100
     local rr = ptable.finish or 100
     local precision = 0.1 or ptable.prec

     local color = ptable.color or 1
     local label = ptable.label or "function" 
     
     local xfunc = ptable.funcx or "..."
     local yfunc = ptable.func or "1"
     local y = load("return "..yfunc)
     local x = load("return "..xfunc)

     
     for t=ll,rr,precision do
        pix(o.x + 10 * x(t/10),
  	  o.y - 10 * y(t/10),
  	  color)
     end

     math.randomseed(y(ll)+y(0)+y(rr))
     local lll = math.random(ll,rr)     
     print(label,
  	 o.x +10 * x(lll/10),
  	 o.y -10 * y(lll/10),
  	 color,false,1,true)
  end

2D Plane - Polar 

  function polar(ptable)
     local ll = -pi or ptable.start
     local rr = pi or ptable.finish
     local precision = 0.01 or ptable.prec

     local color = ptable.color or 2
     local label = ptable.label or "function" 
     
     local rfunc = ptable.func or "1"
     local r = load("return "..rfunc) 

     for t=ll,rr,precision do
        local x = o.x + 10 * r(t) * math.cos(t)
        local y = o.y + 10 * r(t) * math.sin(t)
        pix(x,y,color)
     end

     math.randomseed(r(ll)+r(0)+r(rr))
     local lll = math.random(ll//1,rr//1)
     print(label,
  	 o.x + 10 * r(lll) * math.cos(lll),
  	 o.y + 10 * r(lll) * math.sin(lll),
  	 color,false,1,true)
  end

Axis 

  function axis2d()
     line(0,o.y,
  	240,o.y,
  	12)
     tri(240,o.y,
         235,o.y-5,
         235,o.y+5,
         12)
     line(o.x,0,
  	o.x,136,
  	12)
     tri(o.x,0,
         o.x-5,5,
         o.x+5,5,
         12)
  end

Add functions manually 

  -- ADD FUNCTIONS MANUALLY
  fns={
     {
        func="...^3-2*...+...",
        ptype=plot,
        label="function"
     },
     {
        funcx="2*sin(...)^2",
        func="3*cos(...)",
        ptype=plot,
        label="curve"
     },
     {
        func="2*sin(3*...)+3*cos(2*...)",
        ptype=polar,
        label="polar"
     },
     {
        func   =  "1",
        funcx  =  "...",
        start  = -100,
        finish =  100,
        color  =  4,
        label  =  "template",
        ptype  =  plot,
  }
  }

TIC 

  function TIC()
     -- t=time()
     
     if btnp(0) and fnsi>1    then fnsi = fnsi - 1 end -- up -- key 58
     if btnp(1) and fnsi<#fns then fnsi = fnsi + 1 end -- do -- key 59
     -- if btnp(2) then ; end -- le -- key 60
     -- if btnp(3) then ; end -- ri -- key 61
     
     cls(13)
     axis2d()
     fns[fnsi].ptype(fns[fnsi])
     
  end

Cart data 

-- <TILES>
-- 001:eccccccccc888888caaaaaaaca888888cacccccccacc0ccccacc0ccccacc0ccc
-- 002:ccccceee8888cceeaaaa0cee888a0ceeccca0ccc0cca0c0c0cca0c0c0cca0c0c
-- 003:eccccccccc888888caaaaaaaca888888cacccccccacccccccacc0ccccacc0ccc
-- 004:ccccceee8888cceeaaaa0cee888a0ceeccca0cccccca0c0c0cca0c0c0cca0c0c
-- 017:cacccccccaaaaaaacaaacaaacaaaaccccaaaaaaac8888888cc000cccecccccec
-- 018:ccca00ccaaaa0ccecaaa0ceeaaaa0ceeaaaa0cee8888ccee000cceeecccceeee
-- 019:cacccccccaaaaaaacaaacaaacaaaaccccaaaaaaac8888888cc000cccecccccec
-- 020:ccca00ccaaaa0ccecaaa0ceeaaaa0ceeaaaa0cee8888ccee000cceeecccceeee
-- </TILES>

-- <WAVES>
-- 000:00000000ffffffff00000000ffffffff
-- 001:0123456789abcdeffedcba9876543210
-- 002:0123456789abcdef0123456789abcdef
-- </WAVES>

-- <SFX>
-- 000:000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000304000000000
-- </SFX>

-- <TRACKS>
-- 000:100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
-- </TRACKS>

-- <PALETTE>
-- 000:1a1c2c5d275db13e53ef7d57ffcd75a7f07038b76425717929366f3b5dc941a6f673eff7f4f4f494b0c2566c86333c57
-- </PALETTE>