• Our software update is now concluded. You will need to reset your password to log in. In order to do this, you will have to click "Log in" in the top right corner and then "Forgot your password?".
  • Forum moderator applications are now open! Click here for details.
  • Welcome to PokéCommunity! Register now and join one of the best fan communities on the 'net to talk Pokémon and more! We are not affiliated with The Pokémon Company or Nintendo.

Development: Lua? In MY emulator?

knizz

192
Posts
16
Years
  • Seen Oct 28, 2020
It's likelier than you think!

I forked VBA-M a few days ago to add scripting support and it just reached alpha level.
You can download/star/subscribe the project at https://github.com/dkreuter/VBA-M

You'll have to compile it yourself, and I only have a linux machine to work with, so I don't know if it even works with windows.

Anyway, here are some of the uses I imagine:
  • ROM-Hackers could write their gameplay in a proper programming language instead of pokescript.
  • ROM-Hackers could add features like multiplayer.
    1. Hacker X wants to know to something about offset Y but can't find where Y is used.
    2. X writes a script that triggers when Y is read and uploads it to a server
    3. Somewhere else, the lua-enabled emulator downloads that script and lets it interact with the game.
    4. When the script triggers it uploads a savegame to the server for X to analyze.

I personally want to use it to get traces as nice html.

Feedback? Bug-reports? Questions? Suggestions?
 

knizz

192
Posts
16
Years
  • Seen Oct 28, 2020
UPDATE: The building process for linux users should be fully automated now.

Here's a test-file you can use with my emulator. Put it in the top folder of the project and name it… "pokemon.lua" maybe. Launch the emulator with 'vbam -l firered.gba' in the top folder, press F11, type 'require "pokemon"'. Resume emulation with Ctrl+D. You should see lots of debug output now. (PROFIT!)
Code:
-- Usage:
--  require "pokemon"
--  Ctrl+D

require "bkpt"
bit = require "bit"
stack = require "stack"
stack.over = {}

mute_c3 = false

function pwrite(x)
    io.write(string.format("%-80s", x))
    printtrace()
end

function c3_init_enter()
    print("\n======== RESET C3 ========\n")
    mute_c3 = true
end

function c3_init_leave()
    mute_c3 = false
end

function c3watch_trigger(self, a, b, c)
    if mute_c3 then return end
    local space = ""
    for i=1,self.id do space = space.."            " end
    if a == 0 then
        pwrite(space..string.format("#%02x ", self.id) .. ref(c))
    elseif a == 4 then
        pwrite(space..string.format("#%02x ", self.id) .. (c==1 and "ON" or "OFF"))
    end
end

function dp01watch_trigger(self, a, b, c)
    local space = ""
    for i=1,self.id do space = space.."       " end
    pwrite("DP01 ==== "..space..ref(c))
end

in_script = false
function script_enter() in_script = true  end
function script_leave() in_script = false end
function script_env_trigger(self, a, b, c)
    -- a = offset
    -- b = old value
    -- c = new value
    if a >= 0x74 then
        return
    end
    if a == 0x5C and c ~= 0x0815F9B4 then
        print("!!!!!!!!!!!!!!!!!!!!!!!!!!!")
        print(string.format("New script command table @ %08x", c))
    end
    if not in_script then
        print(string.format("untracked change 0x%08x+%02x %x->%x", self.start, a, b, c))
        printtrace()
    end
end
function script_desc()
    local p = gba.reg(4)
    return string.format("scriptenv %08x @ %08x ", p, gba.mem32(p+8))
end
function script_cmd()
    print(script_desc().."cmd: "..ref(gba.reg(1)))
end
function script_env_init()
    in_script = true
    pwrite(string.format("scriptenv %08x @ reset", gba.reg(4)))
end
function script_status_normal()
    in_script = true
    pwrite(string.format("scriptenv %08x @ %08x LAUNCH", gba.reg(0), gba.reg(1)))
end
function oamt_spawn_from_uns_2()
    pwrite(string.format("OAMt from UNS 2 %08x", gba.reg(0)))
end
function oamt_spawn_from_uns_1()
    pwrite(string.format("OAMt from UNS 1 %08x", gba.reg(0)))
end

-- -- -- -- -- -- -- --

function watch_array(start, count, size, trigger)
    for i=0,count do
        local nw = {}
        nw.id = i
        nw.start = start + size*i
        nw.stop =  start + size*(i+1)
        nw.trigger = trigger
        table.insert(watch, nw)
    end
    gba.oldapi("bpw", string.format("0x%08x", start), string.format("%d", count*size))
end

function watch_simple(pos, size, msg)
    function pp(self, a, b, c)
        pwrite(string.format("%s: %08x+%x: ", msg, self.start, a)..ref(b).." -> "..ref(c))
    end
    local nw = {}
    nw.start = pos
    nw.stop = pos + size
    nw.trigger = pp
    table.insert(watch, nw)
    gba.oldapi("bpw", string.format("0x%08x", pos), string.format("%d", size))
end

function regmodpoint(addr, reg, value)
    function modder()
        gba.reg(reg, value)
    end
    table.insert(bkpts.inactive, addr)
    bkpts.callback[addr] = modder
end

-- -- -- -- -- -- -- --

function install()
    bkpts:add(0x080773BC, c3_init_enter)
    bkpts:add(0x0807740C, c3_init_leave)
    bkpts:add(0x08069804, script_enter)
    bkpts:add(0x0806986E, script_cmd)
    bkpts:add(0x0806987C, script_leave)
    bkpts:add(0x080697AC, script_env_init)
    bkpts:add(0x080697E2, script_leave)
    bkpts:add(0x080697E8, script_status_normal)
    bkpts:add(0x080697F0, script_leave)
    bkpts:add(0x08006F8C, oamt_spawn_from_uns_1)
    bkpts:add(0x08006FE0, oamt_spawn_from_uns_2)

    watch_array(0x03005090, 16, 0x28, c3watch_trigger)
    watch_array(0x03000eb0,  2, 0x78, script_env_trigger)
    watch_array(0x03004FE0, 4, 4, dp01watch_trigger)
    watch_simple(0x03005020, 4, "map loader")
    -- watch_simple(0x030030F0, 8)
    -- watch_simple(0x02023D74, 4)
    -- watch_simple(0x03004F84, 4)

    add_tracepoint(0x08035AC0, "                               ------------AC0", 1)
    -- add_tracepoint(0x0800D8B0, "load dp01 buffer", 1)
    -- add_tracepoint(0x08014068, "", 0)
    -- add_tracepoint(0x08012408, "c1_battle_dp01_bx_r0", 0)

    bkpts:enable()

    -- You probably don't have this file.
    -- loadnames("firered.map")
end

-- -- -- -- -- -- -- --

names = {}

function ref(addr)
    local addr = bit.band(addr, bit.bnot(1))
    return names[addr] or string.format("%08x", addr)
end

function loadnames(fname)
    for line in io.lines(fname) do
        k, v = string.match(line, ":(%x+)       (.+)")
        if k ~= nil then
            names[tonumber(k, 16)+0x08000000] = v
        end
    end
end

-- -- -- -- -- -- -- --

function introskipper()
    gba.mem32(0x080EC5D0, 0x0800C301)
    gba.mem32(0x0800C4C4, 0x08056645)
    gba.mem32(0x080EC5D0, 0x0800C301)
    gba.mem32(0x0800C4C4, 0x08056645) -- Player Name: Kamon
    gba.mem32(0x08054A68, 0x68204C3C)
    gba.mem32(0x08054A6C, 0xE0014900)
    gba.mem32(0x08054A70, 0x081C5797)
    gba.mem16(0x08054A7E, 0x4E34)
    gba.mem16(0x08054B3A, 0x0000)
    gba.mem16(0x08054B3C, 0x0000)
end

-- -- -- -- -- -- -- --

install()
introskipper()

I can't really explain all of it right now. I hope you can figure it out from the lua-files.
 
Last edited:

Shiny Quagsire

I'm Still Alive, Elsewhere
697
Posts
14
Years
Epic!

I can see so much potential with this. If the Lua can be triggered on a RAM write, you could use a writebytetooffset in a pokescript to trigger a lua script, do some stuff, then return!

As for networking, that might take a bit of work for stuff like a DPPt style underground, but I can see some REALLY good but simple uses for networking: Mystery Gifts. Use an online distribution system (or codes based on an online thingy) to get certain items or event pokemon. Or, a GTS to trade pokemon with other ROM-Hack-players. OR, an online saving system where you can view your progress... With networking, the possibilities are endless!

Although, I must request one feature if it's not already existant: Linking (wireless or wired) from a Lua script. While it's possible manually, it's annoyingly difficult. If we could have link connections from lua, we could have a wifi battle system, or a wifi trading system in all the Pokemon Games!
 
Back
Top