✨ add mjx runner

train.py

@@ -1,4 +1,10 @@
+import os
 import pathlib
+import sys
+
+# Headless rendering: use OSMesa on Linux servers (must be set before mujoco import)
+if sys.platform == "linux" and "DISPLAY" not in os.environ:
+    os.environ.setdefault("MUJOCO_GL", "osmesa")
 
 import hydra
 import hydra.utils as hydra_utils
@@ -8,9 +14,9 @@ from hydra.core.hydra_config import HydraConfig
 from omegaconf import DictConfig, OmegaConf
 
 from src.core.env import BaseEnv, BaseEnvConfig, ActuatorConfig
+from src.core.runner import BaseRunner
 from src.envs.cartpole import CartPoleEnv, CartPoleConfig
 from src.envs.rotary_cartpole import RotaryCartPoleEnv, RotaryCartPoleConfig
-from src.runners.mujoco import MuJoCoRunner, MuJoCoRunnerConfig
 from src.training.trainer import Trainer, TrainerConfig
 
 logger = structlog.get_logger()
@@ -41,6 +47,33 @@ def _build_env(env_name: str, cfg: DictConfig) -> BaseEnv:
     return env_cls(config_cls(**env_dict))
 
 
+# ── runner registry ───────────────────────────────────────────────────
+# Maps Hydra config-group name → (RunnerClass, ConfigClass)
+# Imports are deferred so JAX is only loaded when runner=mjx is chosen.
+
+RUNNER_REGISTRY: dict[str, tuple[str, str, str]] = {
+    "mujoco": ("src.runners.mujoco", "MuJoCoRunner", "MuJoCoRunnerConfig"),
+    "mjx":    ("src.runners.mjx",    "MJXRunner",    "MJXRunnerConfig"),
+}
+
+
+def _build_runner(runner_name: str, env: BaseEnv, cfg: DictConfig) -> BaseRunner:
+    """Instantiate the right runner from the Hydra config-group name."""
+    if runner_name not in RUNNER_REGISTRY:
+        raise ValueError(
+            f"Unknown runner '{runner_name}'. Registered: {list(RUNNER_REGISTRY)}"
+        )
+    module_path, cls_name, cfg_cls_name = RUNNER_REGISTRY[runner_name]
+
+    import importlib
+    mod = importlib.import_module(module_path)
+    runner_cls = getattr(mod, cls_name)
+    config_cls = getattr(mod, cfg_cls_name)
+
+    runner_config = config_cls(**OmegaConf.to_container(cfg.runner, resolve=True))
+    return runner_cls(env=env, config=runner_config)
+
+
 def _init_clearml(choices: dict[str, str], remote: bool = False) -> Task:
     """Initialize ClearML task with project structure and tags.
 
@@ -58,7 +91,14 @@ def _init_clearml(choices: dict[str, str], remote: bool = False) -> Task:
     tags = [env_name, runner_name, training_name]
 
     task = Task.init(project_name=project, task_name=task_name, tags=tags)
-    task.set_base_docker("registry.kube.optimize/worker-image:latest")
+    task.set_base_docker(
+        "registry.kube.optimize/worker-image:latest",
+        docker_setup_bash_script=(
+            "apt-get update && apt-get install -y --no-install-recommends "
+            "libosmesa6 libgl1-mesa-glx libglfw3 && rm -rf /var/lib/apt/lists/* "
+            "&& pip install 'jax[cuda12]' mujoco-mjx"
+        ),
+    )
 
     req_file = pathlib.Path(hydra_utils.get_original_cwd()) / "requirements.txt"
     task.set_packages(str(req_file))
@@ -84,10 +124,8 @@ def main(cfg: DictConfig) -> None:
 
     env_name = choices.get("env", "cartpole")
     env = _build_env(env_name, cfg)
-    runner_config = MuJoCoRunnerConfig(**OmegaConf.to_container(cfg.runner, resolve=True))
+    runner = _build_runner(choices.get("runner", "mujoco"), env, cfg)
     trainer_config = TrainerConfig(**training_dict)
-
-    runner = MuJoCoRunner(env=env, config=runner_config)
     trainer = Trainer(runner=runner, config=trainer_config)
 
     try: