Add LightCycles arena (Tron light-cycles)

Thin arena wrapper cloning CodeClash-ai/LightCycles, replay renderer (trail
accumulation + head/crash markers, per-sim winner via peek_winner), registration,
and test config.

Author: john-b-yang

codeclash/arenas/__init__.py

@@ -15,6 +15,7 @@
 from codeclash.arenas.halite2.halite2 import Halite2Arena
 from codeclash.arenas.halite3.halite3 import Halite3Arena
 from codeclash.arenas.huskybench.huskybench import HuskyBenchArena
+from codeclash.arenas.lightcycles.lightcycles import LightCyclesArena
 from codeclash.arenas.paintvolley.paintvolley import PaintVolleyArena
 from codeclash.arenas.robocode.robocode import RoboCodeArena
 from codeclash.arenas.robotrumble.robotrumble import RobotRumbleArena
@@ -37,6 +38,7 @@
     Halite2Arena,
     Halite3Arena,
     HuskyBenchArena,
+    LightCyclesArena,
     PaintVolleyArena,
     RoboCodeArena,
     RobotRumbleArena,

codeclash/arenas/lightcycles/LightCycles.Dockerfile

@@ -0,0 +1,18 @@
+FROM ubuntu:22.04
+
+ENV DEBIAN_FRONTEND=noninteractive
+
+# Install Python 3.10, pip, and prerequisites
+RUN apt-get update \
+ && apt-get install -y --no-install-recommends \
+    curl ca-certificates python3.10 python3.10-venv \
+    python3-pip python-is-python3 wget git build-essential jq curl locales \
+ && rm -rf /var/lib/apt/lists/*
+
+# Clone LightCycles game repository
+RUN git clone https://github.com/CodeClash-ai/LightCycles.git /workspace \
+    && cd /workspace \
+    && git remote set-url origin https://github.com/CodeClash-ai/LightCycles.git
+WORKDIR /workspace
+
+# No additional dependencies needed - engine uses only the standard library

codeclash/arenas/lightcycles/__init__.py

@@ -0,0 +1,88 @@
+import re
+
+from codeclash.agents.player import Player
+from codeclash.arenas.arena import CodeArena, RoundStats
+from codeclash.constants import RESULT_TIE
+from codeclash.utils.environment import assert_zero_exit_code
+
+LIGHTCYCLES_LOG = "result.log"
+
+
+class LightCyclesArena(CodeArena):
+    name: str = "LightCycles"
+    submission: str = "main.py"
+    description: str = """Your bot (`main.py`) drives a cycle in LightCycles, a Tron light-cycles game. Each
+player rides around a bordered grid leaving a solid trail behind. Every tick all cycles move one cell
+simultaneously; you crash (and are eliminated) if you move into a wall/border, any trail (yours or an
+opponent's), or the same cell as another cycle (a head-on). The last cycle riding wins; if all remaining
+cycles crash on the same tick it's a draw; at the tick cap the most territory (trail cells) wins.
+
+Your bot must implement:
+    def get_move(obs: dict) -> str
+
+Return one of "N", "S", "E", "W" (up/down/right/left). Reversing into your own neck is ignored (you go
+straight); an invalid/crashing/slow move also makes you continue straight.
+
+`obs` gives the full deterministic state each tick: obs["tick"]/["max_ticks"], obs["width"]/["height"],
+obs["you"] (your id), obs["players"] (list of {id, x, y, dir, alive}), and obs["grid"]
+(grid[y][x] = owning player id, or -1 for empty; off-grid is a wall). Origin is top-left; N is -y.
+"""
+
+    def __init__(self, config, **kwargs):
+        super().__init__(config, **kwargs)
+        assert len(config["players"]) >= 2, "LightCycles needs at least two players"
+
+    def execute_round(self, agents: list[Player]) -> None:
+        args = [f"/{agent.name}/{self.submission}" for agent in agents]
+        cmd = (
+            f"python engine.py {' '.join(args)} -r {self.game_config['sims_per_round']} "
+            f"-o {self.log_env} > {self.log_env / LIGHTCYCLES_LOG};"
+        )
+        self.logger.info(f"Running game: {cmd}")
+        assert_zero_exit_code(self.environment.execute(cmd))
+
+    def get_results(self, agents: list[Player], round_num: int, stats: RoundStats):
+        with open(self.log_round(round_num) / LIGHTCYCLES_LOG) as f:
+            round_log = f.read()
+        lines = round_log.split("FINAL_RESULTS")[-1].splitlines()
+
+        # Engine prints: "Bot_<i>: <wins> games won (<name>)". Score = games won.
+        scores: dict[str, float] = {}
+        for line in lines:
+            match = re.search(r"Bot_(\d+):\s+(\d+)\s+games\s+won", line)
+            if match:
+                bot_id = int(match.group(1))
+                wins = int(match.group(2))
+                if 1 <= bot_id <= len(agents):
+                    scores[agents[bot_id - 1].name] = wins
+
+        draw_match = re.search(r"Draws:\s+(\d+)", round_log)
+        if draw_match and int(draw_match.group(1)) > 0:
+            scores[RESULT_TIE] = int(draw_match.group(1))
+
+        if scores:
+            real = {k: v for k, v in scores.items() if k != RESULT_TIE}
+            max_score = max(real.values()) if real else 0
+            winners = [k for k, v in real.items() if v == max_score]
+            stats.winner = winners[0] if len(winners) == 1 else RESULT_TIE
+        else:
+            stats.winner = "unknown"
+
+        stats.scores = scores
+        for player, score in scores.items():
+            if player != RESULT_TIE:
+                stats.player_stats[player].score = score
+
+    def validate_code(self, agent: Player) -> tuple[bool, str | None]:
+        if self.submission not in agent.environment.execute("ls")["output"]:
+            return False, f"No {self.submission} file found in the root directory"
+
+        bot_content = agent.environment.execute(f"cat {self.submission}")["output"]
+        if "def get_move(" not in bot_content:
+            return (
+                False,
+                f"{self.submission} must define a get_move(obs) function. "
+                "See the game description for the required signature.",
+            )
+
+        return True, None

codeclash/arenas/lightcycles/lightcycles.py

@@ -0,0 +1,133 @@
+"""LightCycles replay renderer.
+
+Parses a per-game ``sim_*.json`` written by the engine and renders the Tron grid:
+each cycle's growing trail plus its bright head, with a side panel of who's alive.
+
+The JSON format (see engine.py ``write_replay``)::
+
+    {"width":40, "height":30, "num_players":2, "names":["p1","p2"],
+     "winner": 0 | null,
+     "frames":[{"t":0, "heads":[[x,y,alive], ...]}, ...]}
+
+Frames store only each cycle's head (``[x, y, alive]``, ``alive`` is 1/0) per tick;
+the trail for a player is the set of every head cell it has occupied so far, which
+the renderer rebuilds by accumulating heads up to the frame being shown. ``winner``
+is the winning player id, or ``null`` for a draw.
+"""
+
+from __future__ import annotations
+
+import json
+
+from codeclash.replay.base import ReplayData, ReplayRenderer
+
+DRAW_JS = """
+const ARENA = (function(){
+  const PAL = ['#e5484d','#4593ff','#46a758','#f5d90a','#8e4ec6','#f76b15','#e93d82','#12a594'];
+  const BG = '#0d1117', GRID_LINE = 'rgba(255,255,255,0.05)';
+  let W, H, CELL;
+  function col(i){ return PAL[i % PAL.length]; }
+  function setup(cv, G){
+    W = G.w; H = G.h;
+    CELL = Math.max(6, Math.min(20, Math.floor(640 / W)));
+    cv.width = W * CELL; cv.height = H * CELL;
+  }
+  function draw(ctx, cv, G, i){
+    ctx.fillStyle = BG; ctx.fillRect(0, 0, cv.width, cv.height);
+    // faint grid
+    ctx.strokeStyle = GRID_LINE; ctx.lineWidth = 1;
+    for(let x=0;x<=W;x++){ ctx.beginPath(); ctx.moveTo(x*CELL,0); ctx.lineTo(x*CELL,cv.height); ctx.stroke(); }
+    for(let y=0;y<=H;y++){ ctx.beginPath(); ctx.moveTo(0,y*CELL); ctx.lineTo(cv.width,y*CELL); ctx.stroke(); }
+    const n = (G.frames[0].heads || []).length;
+    // rebuild trails by accumulating every head cell up to frame i
+    for(let p=0;p<n;p++){
+      ctx.fillStyle = col(p); ctx.globalAlpha = 0.55;
+      for(let f=0;f<=i;f++){
+        const h = G.frames[f].heads[p];
+        ctx.fillRect(h[0]*CELL, h[1]*CELL, CELL, CELL);
+      }
+      ctx.globalAlpha = 1;
+    }
+    // heads on top (bright, outlined); crashed cycles get an X
+    const fr = G.frames[i];
+    for(let p=0;p<n;p++){
+      const h = fr.heads[p], hx = h[0]*CELL, hy = h[1]*CELL;
+      ctx.fillStyle = col(p);
+      ctx.fillRect(hx, hy, CELL, CELL);
+      ctx.strokeStyle = '#fff'; ctx.lineWidth = 2;
+      ctx.strokeRect(hx+1, hy+1, CELL-2, CELL-2);
+      if(!h[2]){  // crashed
+        ctx.strokeStyle = '#0d1117'; ctx.lineWidth = 2;
+        ctx.beginPath();
+        ctx.moveTo(hx+3, hy+3); ctx.lineTo(hx+CELL-3, hy+CELL-3);
+        ctx.moveTo(hx+CELL-3, hy+3); ctx.lineTo(hx+3, hy+CELL-3);
+        ctx.stroke();
+      }
+    }
+  }
+  function side(G, i){
+    const fr = G.frames[i], NM = G.names || [], n = fr.heads.length;
+    const done = i === G.frames.length - 1;
+    let rows = '';
+    for(let p=0;p<n;p++){
+      const alive = fr.heads[p][2];
+      // territory = distinct cells this cycle has occupied through frame i
+      const cells = new Set();
+      for(let f=0;f<=i;f++){ const h=G.frames[f].heads[p]; cells.add(h[0]+','+h[1]); }
+      rows += `<div class="team ${alive?'':'tdead'}"><div class="tname">`
+        + `<span class="sw" style="background:${col(p)}"></span>`
+        + `${NM[p] || ('player'+(p+1))} ${alive?'':'&#10007;'}</div>`
+        + `<div class="stat"><span>trail</span><b>${cells.size}</b></div></div>`;
+    }
+    const res = done ? (G.draw ? 'DRAW' : (G.winner || '\\u2014')) : '';
+    return rows
+      + `<div class="stat"><span>tick</span><b>${fr.turn} / ${G.max_ticks||''}</b></div>`
+      + (done ? `<div class="stat"><span>result</span><b>${res}</b></div>` : '');
+  }
+  return {setup, draw, side};
+})();
+"""
+
+
+class LightCyclesReplayer(ReplayRenderer):
+    arena = "LightCycles"
+    sim_glob = "sim_*.json"
+    DRAW_JS = DRAW_JS
+
+    def parse(self, raw: bytes, players: list[dict] | None = None) -> ReplayData:
+        log = json.loads(raw.decode(errors="replace"))
+        w = log.get("width", 40)
+        h = log.get("height", 30)
+        n = log.get("num_players", 2)
+
+        names = list(log.get("names", []))
+        if players:
+            names = [p.get("name", names[i] if i < len(names) else f"player{i + 1}") for i, p in enumerate(players)]
+        while len(names) < n:
+            names.append(f"player{len(names) + 1}")
+
+        frames = [{"turn": fr.get("t", idx), "heads": fr["heads"]} for idx, fr in enumerate(log.get("frames", []))]
+
+        win = log.get("winner")
+        draw = win is None
+        winner = None if draw else names[win] if isinstance(win, int) and 0 <= win < len(names) else str(win)
+
+        return ReplayData(
+            w=w,
+            h=h,
+            frames=frames,
+            winner=winner,
+            draw=draw,
+            extra={"names": names, "num_players": n, "max_ticks": log.get("max_ticks")},
+        )
+
+    def peek_winner(self, raw: bytes, players: list[dict] | None = None) -> tuple[str | None, bool] | None:
+        log = json.loads(raw.decode(errors="replace"))
+        win = log.get("winner")
+        if win is None:
+            return (None, True)
+        names = list(log.get("names", []))
+        if players:
+            names = [p.get("name", names[i] if i < len(names) else f"player{i + 1}") for i, p in enumerate(players)]
+        name = names[win] if isinstance(win, int) and 0 <= win < len(names) else str(win)
+        return (name, False)

codeclash/arenas/lightcycles/replay.py

@@ -61,6 +61,10 @@ def get_replayer(arena: str) -> ReplayRenderer | None:
         from codeclash.arenas.paintvolley.replay import PaintVolleyReplayer
 
         return PaintVolleyReplayer()
+    if arena == "LightCycles":
+        from codeclash.arenas.lightcycles.replay import LightCyclesReplayer
+
+        return LightCyclesReplayer()
     if arena == "Halite":
         from codeclash.arenas.halite.replay import HaliteReplayer
 

codeclash/replay/__init__.py

@@ -0,0 +1,30 @@
+tournament:
+  rounds: 3
+game:
+  name: LightCycles
+  sims_per_round: 10
+players:
+- agent: dummy
+  name: p1
+- agent: dummy
+  name: p2
+prompts:
+  game_description: |
+    You are a software developer ({{player_id}}) competing in a coding game called LightCycles.
+    Your bot (`main.py`) drives a cycle in a Tron light-cycles game. Each player rides around a
+    bordered grid leaving a solid trail behind. Every tick all cycles move one cell simultaneously;
+    you crash (and are eliminated) if you move into a wall/border, any trail (yours or an opponent's),
+    or the same cell as another cycle (a head-on). The last cycle riding wins; if all remaining cycles
+    crash on the same tick it's a draw; at the tick cap the most territory (trail cells) wins.
+
+    Your bot must implement `get_move(obs) -> str`, returning one of "N", "S", "E", "W"
+    (up/down/right/left). `obs` is the full deterministic state each tick: obs["tick"]/["max_ticks"],
+    obs["width"]/["height"], obs["you"] (your id), obs["players"] (list of {id, x, y, dir, alive}), and
+    obs["grid"] (grid[y][x] = owning player id, or -1 for empty; off-grid is a wall). Origin is top-left.
+
+    The game is played in {{rounds}} rounds. For every round, you (and your competitor) edit program
+    code that controls your bot. This is round {{round}}.
+    After you and your competitor finish editing your codebases, the game is run automatically.
+
+    Your task: improve the bot in `main.py`, located in {{working_dir}}.
+    {{working_dir}} is your codebase, which contains both your bot and supporting assets.