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# SPDX-FileCopyrightText: Copyright (c) 2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
# SPDX-License-Identifier: Apache-2.0

import os

# ============================================================================
# CRITICAL: Import spaces FIRST, before any CUDA-related packages.
# Disable Gradio's hot-reload watcher in HF Spaces to avoid CUDA initialization
# errors when `spaces` package is imported in a separate thread.
# ============================================================================

try:
    import spaces  # noqa: F401 - imported early for ZeroGPU compatibility
    # Disable Gradio hot-reload in Spaces (prevents thread race conditions)
    os.environ["GRADIO_HOT_RELOAD"] = "False"
except (ImportError, RuntimeError):
    pass  # Not running on HF Spaces with ZeroGPU

import base64
import logging
import shutil
import threading
import time
from typing import Optional

import numpy as np
import torch

import viser
from kimodo.assets import DEMO_ASSETS_ROOT
from kimodo.model.load_model import load_model
from kimodo.model.registry import resolve_model_name
from kimodo.runtime.device import select_runtime_device
from kimodo.skeleton import SkeletonBase, SOMASkeleton30
from kimodo.tools import load_json
from kimodo.viz import viser_utils
from kimodo.viz.viser_utils import (
    Character,
    CharacterMotion,
    EEJointsKeyframeSet,
    FullbodyKeyframeSet,
    RootKeyframe2DSet,
)
from viser.theme import TitlebarButton, TitlebarConfig, TitlebarImage

from . import generation, ui
from .config import (
    DARK_THEME,
    DEFAULT_CUR_DURATION,
    DEFAULT_MODEL,
    DEFAULT_PLAYBACK_SPEED,
    DEFAULT_PROMPT,
    DEMO_UI_QUICK_START_MODAL_MD,
    EXAMPLES_ROOT_DIR,
    HF_MODE,
    LIGHT_THEME,
    MAX_ACTIVE_USERS,
    MAX_DURATION,
    MAX_SESSION_MINUTES,
    MIN_DURATION,
    MODEL_EXAMPLES_DIRS,
    MODEL_NAMES,
    SERVER_NAME,
    SERVER_PORT,
)
from .embedding_cache import CachedTextEncoder
from .queue_manager import QueueManager, UserQueue
from .state import ClientSession, ModelBundle

# Hosted runtimes (HF/Cloud Run) often send non-WS probes to the WS endpoint.
# Suppress noisy stack traces for these expected invalid handshakes.
logging.getLogger("websockets.server").setLevel(logging.CRITICAL)
logging.getLogger("websockets.asyncio.server").setLevel(logging.CRITICAL)


class Demo:
    def __init__(self, default_model_name: str = DEFAULT_MODEL):
        # In hosted HF runtimes (including ZeroGPU), touching CUDA too early can
        # crash startup before queue-managed inference starts.
        requested_device = os.getenv("KIMODO_DEVICE")
        running_in_space = bool(os.getenv("SPACE_ID")) or os.getenv("SYSTEM", "").strip().lower() == "spaces"
        if requested_device is None and (HF_MODE or running_in_space):
            requested_device = "cpu"
        self.device = select_runtime_device(requested=requested_device)
        print(f"Using device: {self.device}")
        self.models: dict[str, ModelBundle] = {}
        resolved = resolve_model_name(default_model_name, "Kimodo")
        if resolved not in MODEL_NAMES:
            raise ValueError(f"Unknown model '{default_model_name}'. Expected one of: {MODEL_NAMES}")
        self.default_model_name = resolved
        self.defer_model_load = os.getenv("KIMODO_DEFER_MODEL_LOAD", "true").strip().lower() in {
            "1",
            "true",
            "yes",
            "on",
        }
        self.ensure_examples_layout()
        if self.defer_model_load:
            print("Deferring model load until first active client session.")
        else:
            self.load_model(self.default_model_name)

        # Serialize GPU-bound generation across all clients
        self._generation_lock = threading.Lock()
        self._cuda_healthy = True

        # Per-client sessions
        self.client_sessions: dict[int, ClientSession] = {}
        self.start_direction_markers: dict[int, viser_utils.WaypointMesh] = {}
        self.grid_handles: dict[int, viser.GridHandle] = {}

        self.server = viser.ViserServer(
            host=SERVER_NAME,
            port=SERVER_PORT,
            label="Kimodo",
            enable_camera_keyboard_controls=False,  # don't move the camera with the arrow keys
        )
        self.server.scene.world_axes.visible = False  # used for debugging
        self.server.scene.set_up_direction("+y")

        # Register callbacks for session handling
        self.server.on_client_connect(self.on_client_connect)
        self.server.on_client_disconnect(self.on_client_disconnect)

        # HF mode: queue and session limit
        if HF_MODE:
            self.user_queue = UserQueue(MAX_ACTIVE_USERS, MAX_SESSION_MINUTES)
            self.queue_manager = QueueManager(
                queue=self.user_queue,
                server=self.server,
                setup_demo_for_client=self._setup_demo_for_client,
                cleanup_session=self._cleanup_session_for_client,
            )
        else:
            self.user_queue = None
            self.queue_manager = None

        # create grid and floor
        self.floor_len = 20.0  # meters

    def ensure_examples_layout(self) -> None:
        os.makedirs(EXAMPLES_ROOT_DIR, exist_ok=True)
        for model_dir in MODEL_EXAMPLES_DIRS.values():
            os.makedirs(model_dir, exist_ok=True)

        for entry in os.listdir(EXAMPLES_ROOT_DIR):
            if entry in MODEL_EXAMPLES_DIRS:
                continue
            src = os.path.join(EXAMPLES_ROOT_DIR, entry)
            if not os.path.isdir(src):
                continue
            dst = os.path.join(
                MODEL_EXAMPLES_DIRS.get(DEFAULT_MODEL, next(iter(MODEL_EXAMPLES_DIRS.values()))),
                entry,
            )
            if not os.path.exists(dst):
                shutil.move(src, dst)

    def get_examples_base_dir(self, model_name: str, absolute: bool = True) -> str:
        return MODEL_EXAMPLES_DIRS[model_name]

    def load_model(self, model_name: str) -> ModelBundle:
        if model_name in self.models:
            return self.models[model_name]

        print(f"Loading model {model_name}...")
        try:
            model = load_model(modelname=model_name, device=self.device)
        except Exception as e:
            print(
                "Error loading model during Kimodo startup. "
                "This often means the text encoder server is not running, the Hugging Face token is missing, "
                "or the gated text encoder model cannot be accessed."
            )
            print(f"Original error: {type(e).__name__}: {e}")
            raise e

        if hasattr(model, "text_encoder"):
            model.text_encoder = CachedTextEncoder(model.text_encoder, model_name=model_name)

        skeleton = model.motion_rep.skeleton
        if isinstance(skeleton, SOMASkeleton30):
            skeleton = skeleton.somaskel77.to(model.device)
        bundle = ModelBundle(
            model=model,
            motion_rep=model.motion_rep,
            skeleton=skeleton,
            model_fps=model.motion_rep.fps,
        )
        self.models[model_name] = bundle
        print(f"Model {model_name} loaded successfully")
        self.prewarm_embedding_cache(model_name, bundle.model)
        return bundle

    def prewarm_embedding_cache(self, model_name: str, model: object) -> None:
        encoder = getattr(model, "text_encoder", None)
        if not isinstance(encoder, CachedTextEncoder):
            return

        prompt_set = set()
        prompt_set.add(DEFAULT_PROMPT)

        examples_dir = MODEL_EXAMPLES_DIRS.get(model_name)
        if examples_dir and os.path.isdir(examples_dir):
            for entry in os.listdir(examples_dir):
                example_dir = os.path.join(examples_dir, entry)
                if not os.path.isdir(example_dir):
                    continue
                meta_path = os.path.join(example_dir, "meta.json")
                if not os.path.exists(meta_path):
                    continue
                try:
                    meta = load_json(meta_path)
                except Exception:
                    continue
                for prompt in meta.get("prompts_text", []):
                    if isinstance(prompt, str):
                        prompt_set.add(prompt)

        if prompt_set:
            try:
                encoder.prewarm(list(prompt_set))
            except Exception as error:
                # Startup should not fail if text encoder is still warming up.
                error_str = str(error)
                if "Encoder initialization failed" in error_str:
                    print(
                        f"⚠️  WARNING: Text encoder failed to initialize: {error}\n"
                        f"  This usually means the HuggingFace gated model cannot be accessed.\n"
                        f"  To fix: Set HF_TOKEN environment variable with access to Meta-Llama-3-8B.\n"
                        f"  Alternatively: Generation will still work but text embeddings may fail."
                    )
                else:
                    print(f"Warning: embedding prewarm skipped: {error}")

    def build_constraint_tracks(
        self, client: viser.ClientHandle, skeleton: SkeletonBase
    ) -> dict[str, viser_utils.ConstraintSet]:
        return {
            "Full-Body": FullbodyKeyframeSet(
                name="Full-Body",
                server=client,
                skeleton=skeleton,
            ),
            "End-Effectors": EEJointsKeyframeSet(
                name="End-Effectors",
                server=client,
                skeleton=skeleton,
            ),
            "2D Root": RootKeyframe2DSet(
                name="2D Root",
                server=client,
                skeleton=skeleton,
            ),
        }

    def set_timeline_defaults(self, timeline, model_fps: float) -> None:
        timeline.set_defaults(
            default_text=DEFAULT_PROMPT,
            default_duration=int(DEFAULT_CUR_DURATION * model_fps - 1),
            min_duration=int(MIN_DURATION * model_fps - 1),  # 2 seconds minimum,
            max_duration=int(
                MAX_DURATION * model_fps - 1  # - NB_TRANSITION_FRAMES
            ),  # 10 seconds maximum, minus the transition frames, if needed
            default_num_frames_zoom=int(1.10 * 10 * model_fps),  # a bit more than the max
            max_frames_zoom=1000,
            fps=model_fps,
        )

    def _apply_constraint_overlay_visibility(self, session: ClientSession) -> None:
        """Apply show-all vs show-only-current-frame to constraint overlays."""
        only_frame = session.frame_idx if session.show_only_current_constraint else None
        for constraint in session.constraints.values():
            constraint.set_overlay_visibility(only_frame)

    def set_constraint_tracks_visible(self, session: ClientSession, visible: bool) -> None:
        timeline = session.client.timeline
        timeline_data = session.timeline_data
        if timeline_data.get("constraint_tracks_visible", True) == visible:
            return

        with timeline_data["keyframe_update_lock"]:
            if visible:
                for track_id, track_info in timeline_data["tracks"].items():
                    timeline.add_track(
                        track_info["name"],
                        track_type=track_info.get("track_type", "keyframe"),
                        color=track_info.get("color"),
                        height_scale=track_info.get("height_scale", 1.0),
                        uuid=track_id,
                    )

                for keyframe_id, keyframe_data in timeline_data["keyframes"].items():
                    timeline.add_keyframe(
                        track_id=keyframe_data["track_id"],
                        frame=keyframe_data["frame"],
                        value=keyframe_data.get("value"),
                        opacity=keyframe_data.get("opacity", 1.0),
                        locked=keyframe_data.get("locked", False),
                        uuid=keyframe_id,
                    )

                for interval_id, interval_data in timeline_data["intervals"].items():
                    timeline.add_interval(
                        track_id=interval_data["track_id"],
                        start_frame=interval_data["start_frame_idx"],
                        end_frame=interval_data["end_frame_idx"],
                        value=interval_data.get("value"),
                        opacity=interval_data.get("opacity", 1.0),
                        locked=interval_data.get("locked", False),
                        uuid=interval_id,
                    )
            else:
                for track_id in list(timeline_data["tracks"].keys()):
                    timeline.remove_track(track_id)

        timeline_data["constraint_tracks_visible"] = visible

    def _cleanup_session_for_client(self, client_id: int) -> None:
        """Remove session and scene state for a client (e.g. on session expiry)."""
        if client_id in self.client_sessions:
            del self.client_sessions[client_id]
        self.start_direction_markers.pop(client_id, None)
        self.grid_handles.pop(client_id, None)

    def _setup_demo_for_client(self, client: viser.ClientHandle) -> None:
        """Initialize scene, GUI, and session state for a client (no modals)."""
        self.setup_scene(client)

        model_bundle = self.load_model(self.default_model_name)

        # Initialize each empty constraint track
        constraint_tracks = self.build_constraint_tracks(client, model_bundle.skeleton)

        # Create GUI elements for this client
        (
            gui_elements,
            timeline_tracks,
            example_dict,
            gui_examples_dropdown,
            gui_save_example_path_text,
            gui_model_selector,
        ) = ui.create_gui(
            demo=self,
            client=client,
            model_name=self.default_model_name,
            model_fps=model_bundle.model_fps,
        )
        timeline_data = {
            "tracks": timeline_tracks,
            "tracks_ids": {val["name"]: key for key, val in timeline_tracks.items()},
            "keyframes": {},
            "intervals": {},
            "keyframe_update_lock": threading.Lock(),
            "keyframe_move_timers": {},
            "pending_keyframe_moves": {},  # keyframe_id -> new_frame
            "constraint_tracks_visible": True,
            "dense_path_after_release_timer": None,
        }

        # Initialize session state
        cur_duration = DEFAULT_CUR_DURATION
        max_frame_idx = int(cur_duration * model_bundle.model_fps - 1)

        session = ClientSession(
            client=client,
            gui_elements=gui_elements,
            motions={},
            constraints=constraint_tracks,
            timeline_data=timeline_data,
            frame_idx=0,
            playing=False,
            playback_speed=DEFAULT_PLAYBACK_SPEED,
            cur_duration=cur_duration,
            max_frame_idx=max_frame_idx,
            updating_motions=False,
            edit_mode=False,
            model_name=self.default_model_name,
            model_fps=model_bundle.model_fps,
            skeleton=model_bundle.skeleton,
            motion_rep=model_bundle.motion_rep,
            examples_base_dir=self.get_examples_base_dir(self.default_model_name, absolute=True),
            example_dict=example_dict,
            gui_examples_dropdown=gui_examples_dropdown,
            gui_save_example_path_text=gui_save_example_path_text,
            gui_model_selector=gui_model_selector,
        )

        self.client_sessions[client.client_id] = session

        # Initialize default character for this client
        self.add_character_motion(client, session.skeleton)

    def on_client_connect(self, client: viser.ClientHandle) -> None:
        """Initialize GUI and state for each new client."""
        print(f"Client {client.client_id} connected")

        if HF_MODE and self.queue_manager is not None:
            self.queue_manager.on_client_connect(client)
        else:
            # Show quick start popup when a browser client connects (non-HF mode).
            with client.gui.add_modal(
                "Welcome — Quick Start",
                size="xl",
                show_close_button=True,
                save_choice="kimodo.demo.quick_start_ack",
            ) as modal:
                client.gui.add_markdown(DEMO_UI_QUICK_START_MODAL_MD)
                client.gui.add_button("Got it (don't remind me again)").on_click(lambda _event: modal.close())
            self._setup_demo_for_client(client)

    def setup_scene(self, client: viser.ClientHandle) -> None:
        self.configure_theme(client)
        client.camera.position = np.array(
            [2.7417358737841426, 1.8790455698853281, 7.675741569777456],
            dtype=np.float64,
        )
        client.camera.look_at = np.array([0.0, 0.0, 0.0], dtype=np.float64)
        client.camera.up_direction = np.array(
            [-1.1102230246251568e-16, 1.0, 1.3596310734468913e-32],
            dtype=np.float64,
        )
        client.camera.fov = np.deg2rad(45.0)
        grid_handle = client.scene.add_grid(
            "/grid",
            width=self.floor_len,
            height=self.floor_len,
            wxyz=viser.transforms.SO3.from_x_radians(-np.pi / 2.0).wxyz,
            position=(0.0, 0.0001, 0.0),
            fade_distance=3 * self.floor_len,
            section_color=LIGHT_THEME["grid"],
            infinite_grid=True,
        )
        self.grid_handles[client.client_id] = grid_handle
        # marker for origin
        origin_waypoint = viser_utils.WaypointMesh(
            "/origin_waypoint",
            client,
            position=np.array([0.0, 0.0, 0.0]),
            heading=np.array([0.0, 1.0]),
            color=(0, 0, 255),
        )
        self.start_direction_markers[client.client_id] = origin_waypoint

    def on_client_disconnect(self, client: viser.ClientHandle) -> None:
        """Clean up when client disconnects."""
        print(f"Client {client.client_id} disconnected")
        client_id = client.client_id

        if HF_MODE and self.queue_manager is not None:
            self.queue_manager.on_client_disconnect(client_id)

        self._cleanup_session_for_client(client_id)

    def set_start_direction_visible(self, client_id: int, visible: bool) -> None:
        marker = self.start_direction_markers.get(client_id)
        if marker is None:
            return
        marker.set_visible(visible)

    def client_active(self, client_id: int) -> bool:
        return client_id in self.client_sessions

    def add_character_motion(
        self,
        client: viser.ClientHandle,
        skeleton: SkeletonBase,
        joints_pos: Optional[torch.Tensor] = None,
        joints_rot: Optional[torch.Tensor] = None,
        foot_contacts: Optional[torch.Tensor] = None,
    ) -> None:
        client_id = client.client_id
        if not self.client_active(client_id):
            return
        session = self.client_sessions[client_id]

        ci = len(session.motions)
        character_name = f"character{ci}"
        # build character skeleton and skinning mesh
        if "g1" in session.model_name:
            mesh_mode = "g1_stl"
        elif "smplx" in session.model_name:
            mesh_mode = "smplx_skin"
        elif "soma" in session.model_name:
            if session.gui_elements.gui_use_soma_layer_checkbox.value:
                mesh_mode = "soma_layer_skin"
            else:
                mesh_mode = "soma_skin"
        else:
            raise ValueError("The model name is not recognized for skinning.")

        new_character = Character(
            character_name,
            client,
            skeleton,
            create_skeleton_mesh=True,
            create_skinned_mesh=True,
            visible_skeleton=False,  # don't show immediately
            visible_skinned_mesh=False,  # don't show immediately
            skinned_mesh_opacity=session.gui_elements.gui_viz_skinned_mesh_opacity_slider.value,
            show_foot_contacts=session.gui_elements.gui_viz_foot_contacts_checkbox.value,
            dark_mode=session.gui_elements.gui_dark_mode_checkbox.value,
            mesh_mode=mesh_mode,
            gui_use_soma_layer_checkbox=session.gui_elements.gui_use_soma_layer_checkbox,
        )

        # if no motion given, initialize to character default (rest) pose for one frame
        init_joints_pos, init_joints_rot = new_character.get_pose()
        if joints_pos is None:
            joints_pos = init_joints_pos[None].repeat(session.max_frame_idx + 1, 1, 1)
        if joints_rot is None:
            joints_rot = init_joints_rot[None].repeat(session.max_frame_idx + 1, 1, 1, 1)

        new_motion = CharacterMotion(new_character, joints_pos, joints_rot, foot_contacts)
        # save the motion in our dict
        session.motions[character_name] = new_motion

        # put the character at the right frame
        new_motion.set_frame(session.frame_idx)

        # put them visible with a small delay
        # so that the set_frame function has time to finish
        def _set_visibility():
            new_motion.character.set_skinned_mesh_visibility(session.gui_elements.gui_viz_skinned_mesh_checkbox.value)
            new_motion.character.set_skeleton_visibility(session.gui_elements.gui_viz_skeleton_checkbox.value)

        timer = threading.Timer(
            0.2,  # 0.2s delay
            _set_visibility,
        )
        timer.start()

    def clear_motions(self, client_id: int) -> None:
        if not self.client_active(client_id):
            return
        session = self.client_sessions[client_id]
        for motion in list(session.motions.values()):
            motion.clear()
        session.motions.clear()

    def compute_model_constraints_lst(
        self,
        session: ClientSession,
        model_bundle: ModelBundle,
        num_frames: int,
    ):
        return generation.compute_model_constraints_lst(session, model_bundle, num_frames, self.device)

    def check_cuda_health(self) -> bool:
        """Check if CUDA is still functional.

        Trigger auto-restart if corrupted.
        """
        if self.device == "cpu":
            return True
        try:
            torch.tensor([1.0], device=self.device) + torch.tensor([1.0], device=self.device)
            return True
        except RuntimeError as e:
            if "device-side assert" in str(e) or "CUDA error" in str(e):
                if self._cuda_healthy:
                    self._cuda_healthy = False
                    print("FATAL: CUDA context is corrupted (device-side assert). " "The process must be restarted.")
                    self._trigger_restart()
                return False
            raise

    def _trigger_restart(self) -> None:
        """Exit the process so the HF Space (or systemd/Docker) can restart it."""
        import sys

        print("Initiating automatic restart due to unrecoverable CUDA error...")
        sys.stdout.flush()
        sys.stderr.flush()
        os._exit(1)

    def generate(
        self,
        client: viser.ClientHandle,
        prompts: list[str],
        num_frames: list[int],
        num_samples: int,
        seed: int,
        diffusion_steps: int,
        cfg_weight: Optional[list[float]] = None,
        cfg_type: Optional[str] = None,
        postprocess_parameters: Optional[dict] = None,
        transitions_parameters: Optional[dict] = None,
        real_robot_rotations: bool = False,
    ) -> None:
        if not self._cuda_healthy:
            raise RuntimeError("CUDA is in a corrupted state. The space is restarting...")

        locked = self._generation_lock.acquire(blocking=False)
        if not locked:
            waiting_notif = client.add_notification(
                title="Waiting for GPU...",
                body="Another generation is in progress. Yours will start automatically.",
                loading=True,
                with_close_button=False,
            )
            self._generation_lock.acquire()
            waiting_notif.remove()

        try:
            session = self.client_sessions[client.client_id]
            model_bundle = self.load_model(session.model_name)
            generation.generate(
                client=client,
                session=session,
                model_bundle=model_bundle,
                prompts=prompts,
                num_frames=num_frames,
                num_samples=num_samples,
                seed=seed,
                diffusion_steps=diffusion_steps,
                cfg_weight=cfg_weight,
                cfg_type=cfg_type,
                postprocess_parameters=postprocess_parameters,
                transitions_parameters=transitions_parameters,
                real_robot_rotations=real_robot_rotations,
                device=self.device,
                clear_motions=self.clear_motions,
                add_character_motion=self.add_character_motion,
            )
        finally:
            self._generation_lock.release()

    def set_frame(self, client_id: int, frame_idx: int, update_timeline: bool = True):
        if not self.client_active(client_id):
            return

        session = self.client_sessions[client_id]

        session.frame_idx = frame_idx
        if update_timeline:
            session.client.timeline.set_current_frame(frame_idx)
        for motion in list(session.motions.values()):
            motion.set_frame(frame_idx)
        self._apply_constraint_overlay_visibility(session)

    def run(self) -> None:
        last_loop_time = time.perf_counter()
        last_cuda_check_time = 0.0
        while True:
            loop_start_time = time.perf_counter()
            delta_time = loop_start_time - last_loop_time
            last_loop_time = loop_start_time

            if self.models:
                # the max playback speed is 2x the model fps (from gui_playback_speed_buttons)
                playback_fps = max(bundle.model_fps for bundle in self.models.values()) * 2.0
            else:
                playback_fps = 60.0

            # update each client session independently
            #   copy to a list first to avoid changing size if client disconnects
            for client_id, session in list(self.client_sessions.items()):
                if not session.playing:
                    continue
                if session.model_fps <= 0:
                    continue

                # Time-based stepping keeps playback smooth even if loop cadence jitters.
                session.playback_time_accumulator += max(0.0, delta_time) * max(0.0, session.playback_speed)
                frame_period = 1.0 / session.model_fps
                if session.playback_time_accumulator < frame_period:
                    continue

                frames_to_advance = int(session.playback_time_accumulator / frame_period)
                session.playback_time_accumulator -= frames_to_advance * frame_period
                frame_count = max(1, session.max_frame_idx + 1)
                new_frame_idx = (session.frame_idx + frames_to_advance) % frame_count

                # make sure the client is still active before updating the frame
                if self.client_active(client_id):
                    self.set_frame(client_id, new_frame_idx)

            if loop_start_time - last_cuda_check_time >= 5.0:
                self.check_cuda_health()
                last_cuda_check_time = loop_start_time

            time_remaining = max(0.0, 1.0 / playback_fps - (time.perf_counter() - loop_start_time))
            time.sleep(time_remaining)

    def configure_theme(
        self,
        client: viser.ClientHandle,
        dark_mode: bool = False,
        titlebar_dark_mode_checkbox_uuid: str | None = None,
    ):
        # Sync grid color with theme (light vs dark)
        theme = DARK_THEME if dark_mode else LIGHT_THEME
        grid_handle = self.grid_handles.get(client.client_id)
        if grid_handle is not None:
            grid_handle.section_color = theme["grid"]

        #
        # setup theme
        #
        buttons = (
            TitlebarButton(
                text="Documentation",
                icon="Description",
                href="https://research.nvidia.com/labs/sil/projects/kimodo/docs/interactive_demo/index.html",
            ),
            TitlebarButton(
                text="Project Page",
                icon=None,
                href="https://research.nvidia.com/labs/sil/projects/kimodo/",
            ),
            TitlebarButton(
                text="Github",
                icon="GitHub",
                href="https://github.com/nv-tlabs/kimodo",
            ),
        )
        assets_dir = DEMO_ASSETS_ROOT
        logo_light_path = assets_dir / "nvidia_logo.png"
        logo_dark_path = assets_dir / "nvidia_logo_dark.png"
        if logo_light_path.exists():
            light_b64 = base64.standard_b64encode(logo_light_path.read_bytes()).decode("ascii")
            dark_b64 = (
                base64.standard_b64encode(logo_dark_path.read_bytes()).decode("ascii")
                if logo_dark_path.exists()
                else None
            )
            image = TitlebarImage(
                image_url_light=f"data:image/png;base64,{light_b64}",
                image_url_dark=(f"data:image/png;base64,{dark_b64}" if dark_b64 else None),
                image_alt="NVIDIA",
                href="https://www.nvidia.com/",
            )
        else:
            image = None
        titlebar_theme = TitlebarConfig(buttons=buttons, image=image, title_text="Movimento")
        client.gui.set_panel_label("Movimento")
        client.gui.configure_theme(
            titlebar_content=titlebar_theme,
            control_layout="floating",  # "floating",  # ['floating', 'collapsible', 'fixed']
            control_width="large",  # ['small', 'medium', 'large']
            dark_mode=dark_mode,
            show_logo=False,  # hide viser logo on bottom left corner
            show_share_button=False,
            titlebar_dark_mode_checkbox_uuid=titlebar_dark_mode_checkbox_uuid,
            brand_color=(152, 189, 255),  # (60, 131, 0),  # (R, G, B) tuple
        )