feat(SAC_LSTM_Bot): skeleton bot with radar lock and colors (#40)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

SAC_LSTM_Bot/config.nims

@@ -9,3 +9,4 @@ when withDir(thisDir(), system.fileExists("nimble.paths")):
 # Use the repo-vendored Tank Royale bot API (libs/) instead of the nimble pkg.
 # Must come AFTER the nimble.paths include: later --path wins the import search.
 switch("path", thisDir() & "/../libs/tankroyale_botapi")
+switch("path", thisDir() & "/../libs/radar_lock")

SAC_LSTM_Bot/src/SAC_LSTM_Bot.json

@@ -0,0 +1,11 @@
+{
+  "name": "Recurrent Royalty",
+  "version": "0.1.0",
+  "authors": ["Davide Cappellini"],
+  "description": "SAC+LSTM Tank Royale bot — skeleton with radar lock",
+  "homepage": "",
+  "countryCodes": ["IT"],
+  "gameTypes": ["classic", "melee", "1v1"],
+  "platform": "Nim",
+  "programmingLang": "Nim"
+}

SAC_LSTM_Bot/src/SAC_LSTM_Bot.nim

@@ -1,4 +1,60 @@
-## SAC_LSTM_Bot — placeholder main module.
+## SAC_LSTM_Bot — skeleton: radar lock + "Recurrent Royalty" color scheme.
-## SAC (Soft Actor-Critic) + LSTM Tank Royale bot.
+## No RL yet. Connects, sets colors, locks radar onto enemy.
 
-echo "SAC_LSTM_Bot scaffold"
+import std/os
+import tankroyale_botapi
+import radar_lock
+
+const botJsonPath = currentSourcePath().parentDir / "SAC_LSTM_Bot.json"
+
+# ── Colors (Recurrent Royalty palette) ───────────────────────────────────────
+const
+  ColBody   = fromHex("#7B2FBE")
+  ColTurret = fromHex("#FFD700")
+  ColGun    = fromHex("#4A0E6B")
+  ColRadar  = fromHex("#FFD700")
+  ColScan   = fromHex("#FFB000")
+  ColBullet = fromHex("#FFC125")
+  ColTracks = fromHex("#2C2C34")
+
+proc applyColors() =
+  setBodyColor(ColBody)
+  setTurretColor(ColTurret)
+  setGunColor(ColGun)
+  setRadarColor(ColRadar)
+  setScanColor(ColScan)
+  setBulletColor(ColBullet)
+  setTracksColor(ColTracks)
+
+# ── Bot type ──────────────────────────────────────────────────────────────────
+
+type SacBot = ref object of Bot
+  enemyBearing: float  # last known absolute bearing to enemy
+
+# ── Event handlers ────────────────────────────────────────────────────────────
+
+method onRoundStarted*(bot: SacBot, e: RoundStartedEvent) =
+  setAdjustRadarForBodyTurn(true)
+  setAdjustRadarForGunTurn(true)
+  radar_lock.init()
+  applyColors()
+
+method onScannedBot*(bot: SacBot, e: ScannedBotEvent) =
+  bot.enemyBearing = directionTo(getX(), getY(), e.x, e.y)
+  # Same-tick radar lock: apply turn rate immediately so it takes effect this tick.
+  setRadarTurnRate(radar_lock.doRadar(getRadarDirection(), bot.enemyBearing))
+
+# ── Run loop ──────────────────────────────────────────────────────────────────
+
+method run(bot: SacBot) =
+  while isRunning():
+    # Spin radar when no enemy is visible (full sweep).
+    if bot.enemyBearing == 0.0:
+      setRadarTurnRate(45.0)
+    go()
+
+# ── Entry point ───────────────────────────────────────────────────────────────
+
+when isMainModule:
+  var bot = SacBot()
+  start(bot, botJsonPath)