Print the Gen 3 Pokédex heights and weights in metric units

FireRed/LeafGreen's, Ruby/Sapphire's and Emerald's Pokédex pages print a species' height in feet and inches and its weight in pounds, converted from the cart's decimetres and hectograms; the localized carts print metres and kilograms. A mod can now give a Gen 3 species its metric height and weight the way it can on Red/Blue and Gold/Silver: the Gen 3 dexEntry schema takes heightM and weightKg, and a patch carries them into the dex table Pokemon.dexEntry reads.

src/core/game3/pokedex_units.lua tells whether a species has them, without loading the dex table itself, and formats them with one decimal and a comma before Strings("m") and Strings("kg"). FireRed/LeafGreen's entry page uses them for a seen or caught species, resolved once per species and caught state rather than on every draw; Ruby/Sapphire's and Emerald's entry pages use them for a caught species, each aligning the digits as its imperial weight does (two spaces per missing digit on Ruby/Sapphire's native page, as the cart's metric printer shifts the number by a digit's width, pokeruby src/pokedex.c:4300; {UNK_SPACER} on Emerald's), and keep the cart's unknown rows for a seen one.

src/core/game3/pokedex_units.lua

@@ -0,0 +1,34 @@
+local Strings = require("src.core.Strings")
+
+local Units = {}
+
+function Units.metric(species)
+  local Pokemon = require("src.core.game3.pokemon")
+  if Pokemon._dex == nil then return nil end
+  local ok, entry = pcall(Pokemon.dexEntry, species)
+  if ok and type(entry) == "table" and entry.heightM and entry.weightKg then return entry end
+  return nil
+end
+
+local function decimal(value, pad)
+  local text = (("%.1f"):format(value or 0):gsub("%.", ","))
+  return string.rep(pad or " ", math.max(0, 5 - #text)) .. text
+end
+
+function Units.height(entry, pad)
+  return decimal(entry.heightM, pad) .. " " .. Strings("m")
+end
+
+function Units.weight(entry, pad)
+  return decimal(entry.weightKg, pad) .. " " .. Strings("kg")
+end
+
+function Units.unknownHeight()
+  return "???,? " .. Strings("m")
+end
+
+function Units.unknownWeight()
+  return "???,? " .. Strings("kg")
+end
+
+return Units

src/mods/Schemas.lua

@@ -1222,7 +1222,8 @@ local function monRecord(base, id)
   local entry = national and t.dex and t.dex[national]
   if entry then
     record.dexEntry = { kind = entry.category or "", height = entry.height or 0,
-                        weight = entry.weight or 0 }
+                        weight = entry.weight or 0, heightM = entry.heightM,
+                        weightKg = entry.weightKg }
   end
   return record
 end
@@ -1346,6 +1347,8 @@ local function writeMon(target, t, num, value)
       category = value.dexEntry.kind or old.category,
       height = value.dexEntry.height or old.height,
       weight = value.dexEntry.weight or old.weight,
+      heightM = value.dexEntry.heightM or old.heightM,
+      weightKg = value.dexEntry.weightKg or old.weightKg,
     }
   end
   local sprites = sideTable(target, "spriteOverrides")
@@ -1847,7 +1850,8 @@ R.pokemon = {
                                item = f.opt(f.id("items")),
                                param = f.opt(f.int(0)) }),
     dexEntry = f.opt(f.rec{ kind = f.str, height = f.int(0),
-                            weight = f.int(0) }),
+                            weight = f.int(0), heightM = f.opt(f.num),
+                            weightKg = f.opt(f.num) }),
     spriteFront = f.path, spriteBack = f.path,
     trueColor = f.opt(f.bool),
   },

src/ui/game3/pokedex.lua

@@ -239,6 +239,7 @@ function Pokedex.showRegistration(speciesId, opts)
   opts = opts or {}
   Pokedex.open = true
   Pokedex._regSpecies = tonumber(speciesId) or 1
+  Pokedex._unitTexts = nil
   Pokedex.selectedSpecies = Pokedex._regSpecies
   Pokedex._session = opts.session
   Pokedex._dex = (opts.session and opts.session.dex) or Dex.new()
@@ -269,6 +270,7 @@ end
 
 -- pokedex_screen.c
 function Pokedex.resetScreenState()
+  Pokedex._unitTexts = nil
   Pokedex.screen = "mode_select"
   Pokedex.subScreenPrev = "mode_select"
   Pokedex.modeCursor = 2
@@ -856,6 +858,20 @@ function Pokedex.controlInfoForDataPage(screen)
   return RomText.plain("gText_Cry"), RomText.plain("gText_NextDataCancel")
 end
 
+local function unitTexts(sp, caught)
+  local memo = Pokedex._unitTexts
+  if memo and memo.sp == sp and memo.caught == caught then return memo end
+  local Units = require("src.core.game3.pokedex_units")
+  local metric = Units.metric(sp)
+  memo = { sp = sp, caught = caught }
+  if metric then
+    memo.height = caught and Units.height(metric) or Units.unknownHeight()
+    memo.weight = caught and Units.weight(metric) or Units.unknownWeight()
+  end
+  Pokedex._unitTexts = memo
+  return memo
+end
+
 --- 3. Detailed Data Entry Screen (Page 1: Specs & Flavor Text, Page 2: Size Chart & Area Map)
 local function draw_data_screen()
   local dex = Pokedex._dex
@@ -903,13 +919,14 @@ local function draw_data_screen()
 
     -- Line 3 (y = 60): HT in FONT_SMALL at x=16; Height value at x=46
     FrlgFont.draw(RomText.plain("gText_HT"), 16, 60, { small = true, colors = upperColors })
-    local htStr = isCaught and (entry.heightFormatted or " ??'??\"") or " ??'??\""
+    local units = unitTexts(sp, isCaught)
+    local htStr = units.height or (isCaught and (entry.heightFormatted or " ??'??\"") or " ??'??\"")
     FrlgFont.draw(htStr, 46, 60, { small = true, colors = upperColors })
 
     -- Line 4 (y = 72): WT in FONT_SMALL at x=16; Weight value at x=46
     FrlgFont.draw(RomText.plain("gText_WT"), 16, 72, { small = true, colors = upperColors })
     -- src/pokedex_screen.c:2834
-    local wtStr = isCaught and entry.weightFormatted or ("????.? " .. RomText.plain("gText_Lbs"))
+    local wtStr = units.weight or (isCaught and entry.weightFormatted or ("????.? " .. RomText.plain("gText_Lbs")))
     FrlgFont.draw(wtStr, 46, 72, { small = true, colors = upperColors })
 
     -- Footprint (16x16) at screen x=104, y=64 (window x=88, y=40)

src/ui/game3/rse/pokedex.lua

@@ -1,5 +1,6 @@
 local Kit = require("src.ui.game3.rse.scene_kit")
 local Strings = require("src.core.Strings")
+local Units = require("src.core.game3.pokedex_units")
 local FrlgFont = require("src.ui.game3.frlg_font")
 local RomText = require("src.core.game3.rom_text")
 local Pal = require("src.core.game3.pal_fade")
@@ -946,8 +947,9 @@ local function monInfo(s, nat, nationalNumber, owned, newEntry)
     local category = owned and (Strings(e.category or "") .. categorySuffix(unknown)) or unknown
     local cx = 88 + (owned and (FrlgFont.measure(unknown) - FrlgFont.measure(category)) or 0)
     out[#out + 1] = {text = category, x = cx, y = 40}
-    out[#out + 1] = {text = owned and Pokedex.heightText(e.height or 0) or rsString("UnknownHeight"), x = 128, y = 56}
-    out[#out + 1] = {text = owned and RsPolicy.weightText(e.weight or 0) or rsString("UnknownWeight"), x = 128, y = 72}
+    local metric = owned and Units.metric(Pokedex.speciesOf(nat))
+    out[#out + 1] = {text = metric and Units.height(metric, "  ") or owned and Pokedex.heightText(e.height or 0) or rsString("UnknownHeight"), x = 128, y = 56}
+    out[#out + 1] = {text = metric and Units.weight(metric, "  ") or owned and RsPolicy.weightText(e.weight or 0) or rsString("UnknownWeight"), x = 128, y = 72}
     local desc
     if s.descriptionPage == 1 then
       desc = cached(e.descriptionLabel2, e.description2)
@@ -975,7 +977,11 @@ local function monInfo(s, nat, nationalNumber, owned, newEntry)
   out[#out + 1] = { text = category, x = 0x64, y = 0x29 }
   out[#out + 1] = { text = RomText.plain("gText_HTHeight"), x = 0x60, y = 0x39 }
   out[#out + 1] = { text = RomText.plain("gText_WTWeight"), x = 0x60, y = 0x49 }
-  if owned then
+  local metric = owned and Units.metric(sp)
+  if metric then
+    out[#out + 1] = { text = Units.height(metric, "{UNK_SPACER}"), x = 0x81, y = 0x39 }
+    out[#out + 1] = { text = Units.weight(metric, "{UNK_SPACER}"), x = 0x81, y = 0x49 }
+  elseif owned then
     out[#out + 1] = { text = Pokedex.heightText(e.height or 0), x = 0x81, y = 0x39 }
     out[#out + 1] = { text = Pokedex.weightText(e.weight or 0), x = 0x81, y = 0x49 }
   else

tests/engine/game3_pokedex_metric_units_test.lua

@@ -0,0 +1,65 @@
+#!/usr/bin/env luajit
+package.path = "./?.lua;./?/init.lua;" .. package.path
+_G.love = _G.love or require("tests.love_stub")
+
+local T = require("tests.harness")
+local check = T.check
+
+T.suite("game3 pokedex metric units")
+
+local Schemas = require("src.mods.Schemas")
+local target = { _names = { [1] = "BULBASAUR" }, _dex = { [1] = { category = "SEED", height = 7, weight = 69 } } }
+local patched = { dexEntry = { kind = "SEED", height = 7, weight = 69, heightM = 0.7, weightKg = 6.9 } }
+Schemas.gen3View.monWrite(target, { ops = { BULBASAUR = true }, get = function() return patched end })
+local row = target._dex[1]
+check(row.heightM == 0.7 and row.weightKg == 6.9 and row.height == 7 and row.category == "SEED",
+  "a patch's metric values reach the dex table beside the cart's")
+
+local DEX = { [252] = { category = "WOOD GECKO", height = 5, weight = 50, heightM = 0.5, weightKg = 5 },
+  [253] = { category = "WOOD GECKO", height = 9, weight = 216 } }
+package.loaded["src.core.game3.pokemon"] = { _dex = DEX,
+  dexEntry = function(species) return DEX[species] end,
+  name = function() return "TREECKO" end,
+  speciesFromNational = function(nat) return nat end,
+}
+
+local Units = require("src.core.game3.pokedex_units")
+check(Units.metric(252) == DEX[252] and Units.metric(253) == nil, "only a species with metric values is metric")
+check(Units.height(DEX[252]) == "  0,5 m" and Units.weight(DEX[252]) == "  5,0 kg",
+  "a metric height and weight print with one decimal and a comma")
+check(Units.weight({ weightKg = 950 }) == "950,0 kg", "a three-digit weight fills the field")
+check(Units.unknownHeight() == "???,? m" and Units.unknownWeight() == "???,? kg", "the unknown masks")
+
+local MANIFEST = { assetLayout = "emerald", tenDashes = "----------",
+  strings = { UnknownPoke = "?????POKéMON", UnknownHeight = "??'??\"", UnknownWeight = "????.? lbs." } }
+package.loaded["src.ui.game3.rse.pokedex_gfx"] = setmetatable({ manifest = function() return MANIFEST end },
+  { __index = function() return function() end end })
+package.loaded["src.ui.game3.rse.mapsec"] = setmetatable({ readLua = function(path)
+  if path:find("entries", 1, true) then return DEX end
+  return { nationalToRegional = {} }
+end }, { __index = function() return function() end end })
+local BUNDLE = { text = {} }
+package.loaded["src.core.game3.scripting.space"] = { ensureBundle = function() return BUNDLE end }
+local Pokedex = require("src.ui.game3.rse.pokedex")
+local function rows(nat, owned)
+  local out = {}
+  for _, r in ipairs(Pokedex.monInfo({ descriptionPage = 0 }, nat, true, owned, false)) do out[#out + 1] = r.text end
+  return table.concat(out, "|")
+end
+MANIFEST.assetLayout = "rs"
+check(rows(252, true):find("|    0,5 m|    5,0 kg|", 1, true) ~= nil,
+  "a caught Ruby/Sapphire entry prints its metric values, two spaces per missing digit")
+check(rows(253, true):find("lbs.", 1, true) ~= nil, "a Ruby/Sapphire entry without metric values keeps the US ones")
+check(rows(252, false):find("????.? lbs.", 1, true) ~= nil, "a seen Ruby/Sapphire entry keeps the cart's unknown rows")
+
+local function ir(text) return { { t = "text", s = text }, { t = "eos" } } end
+BUNDLE.text = { gText_Pokemon = ir("POKéMON"), gText_5MarksPokemon = ir("?????POKéMON"), gText_NumberClear01 = ir("No. "),
+  gText_HTHeight = ir("HT"), gText_WTWeight = ir("WT"),
+  gText_UnkHeight = ir("???,? m"), gText_UnkWeight = ir("???,? kg") }
+MANIFEST.assetLayout = "emerald"
+check(rows(252, true):find("{UNK_SPACER}{UNK_SPACER}0,5 m|{UNK_SPACER}{UNK_SPACER}5,0 kg", 1, true) ~= nil,
+  "a caught Emerald entry prints its metric values aligned with the digit spacer")
+check(rows(253, true):find("lbs.", 1, true) ~= nil, "an Emerald entry without metric values keeps the US ones")
+check(rows(252, false):find("???,? m|???,? kg", 1, true) ~= nil, "a seen Emerald entry prints the cart's unknown rows")
+
+T.finish("game3 pokedex metric units")