terranigma_exp_timer.lua

-- Convert EXP info from HEX 2 DEC
local function loadExp(address)
  local exp = 0
  for n=0,2 do
    local expByte = memory.readbyte(address+n)
    exp = exp + (AND(expByte,0xf) + AND(expByte,0xf0)/0x10*10) * math.pow(100,n)
  end
  return exp
end

-- Detect ROM version
local expTable = 0;
local fps = 60;
local expTableEU = 0x8db92a
local expTableJPN = 0x8dba61--0x8db92a--
if loadExp(expTableEU + 11*49) == 802435 then
    -- European ROM
    expTable = expTableEU
    fps = 50
elseif loadExp(expTableJPN + 11*49) == 802435 then
    -- Japanese ROM
    expTable = expTableJPN
    fps = 60
else
    error(string.format("Could not detect valid Terranigma ROM: %s",loadExp(expTableJPN + 11*1)))
end

-- Create exp timer

--exp.xpos      = 92
--exp.ypos      = 6
local boxcolor          = 0x00000080
local activetextcolor   = 0xFFFFFFFF
local inactivetextcolor = 0x808080FF

local timerIsActive = false
local startFrame    = 0
local totalFrames   = 0
local startExp      = 0
local totalExp      = 0
local previousFrame = 0
local levelUp        = false
local lostControl    = false

local smallHeight = 10
local fullHeight = 2+8*4

local currentHeight = fullHeight
local targetHeight = fullHeight

local xpos = 92
local ypos = 2

local hidden = false

-- Function to render the timer
local function my_display()

  if(currentHeight < targetHeight) then
    currentHeight = currentHeight + 1
  elseif(currentHeight > targetHeight) then
    currentHeight = currentHeight - 1
  end

  local level      = memory.readbyte(0x7e0656)
  local currentExp = loadExp(0x7e0690)
  local targetExp  = loadExp(expTable + 11*level)
  local currentFrame = emu.framecount()

  if(currentExp>targetExp and not levelUp) then
    levelUp         = true
    lostControl     = false
  end

  if levelUp then
    if lostControl then
      lostControl = memory.readbyte(0x7e097d)==0x80
      levelUp = lostControl
      if levelUp and timerIsActive and not (currentFrame==previousFrame) then
        startFrame = startFrame + 1
      end
    else
      lostControl = memory.readbyte(0x7e097d)==0x80
    end
  end

  if timerIsActive then
    totalExp    = currentExp  -startExp
    totalFrames = currentFrame-startFrame
  end

  local expSpeed
  if totalFrames==0 then
    expSpeed = 0
  else
    expSpeed = totalExp/totalFrames*fps
  end

  if hidden then
    return
  end

  gui.box(xpos,ypos,xpos+(17+1)*4,ypos+currentHeight,boxcolor)

  gui.text(xpos+3,ypos+2+8*0,string.format("EXP %13s", string.format("%i / %i",currentExp,targetExp)),textcolor)

  local timerTextColor
  if timerIsActive then timerTextColor = activetextcolor else timerTextColor = inactivetextcolor end

  if currentHeight>=16 then
    gui.text(xpos+3,ypos+2+8*1,string.format("GAIN %12s", string.format("%6i exp",totalExp)),timerTextColor)
  end
  if currentHeight>=24 then
    gui.text(xpos+3,ypos+2+8*2,string.format("TIME %12s", string.format("%6.1f sec",totalFrames/50)),timerTextColor)
  end
  if currentHeight>=32 then
    gui.text(xpos+3,ypos+2+8*3,string.format("SPEED %11s",string.format("%6.1f x/s",expSpeed)),timerTextColor)
  end

  previousFrame = currentFrame
end

-- Hook the display function to the GUI update
local on_gui_update_old = gui.register()
local function on_gui_update_new()
  if on_gui_update_old then
    on_gui_update_old()
  end
  my_display()
end
gui.register(on_gui_update_new)

-- Public functions to control the timer
exp_timer = {}

function exp_timer.show() hidden = false end
function exp_timer.hide() hidden = true  end

function exp_timer.start()
  totalExp      = 0
  startExp      = loadExp(0x7e0690)
  startFrame    = emu.framecount()
  totalFrames   = 0
  timerIsActive = true
end

function exp_timer.stop()
  timerIsActive = false
end

function exp_timer.toggle()
  if timerIsActive then
    exp_timer.stop()
  else
    exp_timer.start()
  end
end

function exp_timer.clear()
  totalExp    = 0
  totalFrames = 0
end

function exp_timer.collapse()
  targetHeight = smallHeight
end

function exp_timer.expand()
  targetHeight = fullHeight
end