Visualization

Isaac Lab offers several lightweight visualizers for real-time simulation inspection and debugging. Unlike renderers that process sensor data, visualizers are meant for fast, interactive feedback.

You can use any visualizer regardless of your chosen physics engine or rendering backend.

Overview

Isaac Lab supports four visualizer backends, each optimized for different use cases:

Visualizer Comparison

Visualizer	Best For	Key Features
Omniverse	High-fidelity, Isaac Sim integration	USD, visual markers, live plots
Newton	Fast iteration	Low overhead, visual markers
Rerun	Remote viewing, replay	Webviewer, time scrubbing, recording export
Viser	Web-based remote visualization, sharing, recording	Warp-based rendering, browser-based, share URL

The following visualizers are shown training the Isaac-Velocity-Flat-Anymal-D-v0 environment.

Omniverse Visualizer

Newton Visualizer

Rerun Visualizer

Quick Start

Launch visualizers from the command line with --visualizer (or --viz alias):

# Launch all visualizers (comma-delimited list, no spaces)
python scripts/reinforcement_learning/rsl_rl/train.py --task Isaac-Cartpole-v0 --viz kit,newton,rerun

# Launch only the Newton visualizer
python scripts/reinforcement_learning/rsl_rl/train.py --task Isaac-Cartpole-v0 --viz newton

# Launch the Viser web-based visualizer
python scripts/reinforcement_learning/rsl_rl/train.py --task Isaac-Cartpole-v0 --viz viser

To run in headless mode, omit the --viz argument:

python scripts/reinforcement_learning/rsl_rl/train.py --task Isaac-Cartpole-v0

Note

The --headless argument is deprecated. For compatibility, --headless still takes precedence and disables all visualizers.

Configuration

Launching visualizers with the command line will use default visualizer configurations. Visualizer backends live in the isaaclab_visualizers package (e.g. source/isaaclab_visualizers/isaaclab_visualizers/kit, newton, rerun, viser).

You can also configure custom visualizers in the code by defining VisualizerCfg instances for the SimulationCfg, for example:

from isaaclab.sim import SimulationCfg
from isaaclab_visualizers.kit import KitVisualizerCfg
from isaaclab_visualizers.newton import NewtonVisualizerCfg
from isaaclab_visualizers.rerun import RerunVisualizerCfg
from isaaclab_visualizers.viser import ViserVisualizerCfg

sim_cfg = SimulationCfg(
    visualizer_cfgs=[
        KitVisualizerCfg(
            viewport_name="Visualizer Viewport",
            create_viewport=True,
            dock_position="SAME",
            window_width=1280,
            window_height=720,
            camera_position=(0.0, 0.0, 20.0), # high top down view
            camera_target=(0.0, 0.0, 0.0),
        ),
        NewtonVisualizerCfg(
            camera_position=(5.0, 5.0, 5.0), # closer quarter view
            camera_target=(0.0, 0.0, 0.0),
            show_joints=True,
        ),
        RerunVisualizerCfg(
            keep_historical_data=True,
            keep_scalar_history=True,
            record_to_rrd="my_training.rrd",
        ),
        ViserVisualizerCfg(
            port=8080,
            share=False,
        ),
    ]
)

Resolution Rules (CLI + Config)

The effective visualizer mode is resolved from both CLI and SimulationCfg.visualizer_cfgs:

• --viz (alias: --visualizer) uses comma-separated values (for example --viz kit,newton).

• If --viz is omitted, Isaac Lab falls back to SimulationCfg.visualizer_cfgs (see Configuration).

• --viz none explicitly disables all visualizers.

• If --headless is passed, it overrides --viz and disables visualizers.

For the migration-focused summary and deprecation context, see Migrating to Isaac Lab 3.0.

Common modes

CLI args	visualizer configs	Effective behavior
no --viz	[]	Run headless.
--viz kit,newton	[]	Launch default Kit and default Newton visualizers.
--viz kit,newton	[NewtonVisualizerCfg(...), RerunVisualizerCfg(...)]	Launch default Kit and custom Newton; Rerun is not launched.
no --viz	[NewtonVisualizerCfg(...), RerunVisualizerCfg(...)]	Launch custom Newton and custom Rerun visualizers from config.
--viz none	[NewtonVisualizerCfg(...), RerunVisualizerCfg(...)]	Run headless with all visualizers disabled.
--headless	any	Run headless with deprecation warning.
--headless --viz <names>	any	Run headless; --headless takes precedence.

Visualizer Backends

Omniverse Visualizer

Main Features:

• Native USD stage integration

• Visualization markers for debugging (arrows, frames, points, etc.)

• Live plots for monitoring training metrics

• Full Isaac Sim rendering capabilities and tooling

Core Configuration:

from isaaclab_visualizers.kit import KitVisualizerCfg

visualizer_cfg = KitVisualizerCfg(
    # Viewport settings
    viewport_name="Visualizer Viewport",      # Viewport window name
    create_viewport=True,                     # Create new viewport vs. use existing
    dock_position="SAME",                     # Docking: 'LEFT', 'RIGHT', 'BOTTOM', 'SAME'
    window_width=1280,                        # Viewport width in pixels
    window_height=720,                        # Viewport height in pixels

    # Camera settings
    camera_position=(8.0, 8.0, 3.0),         # Initial camera position (x, y, z)
    camera_target=(0.0, 0.0, 0.0),           # Camera look-at target

    # Feature toggles
    enable_markers=True,                      # Enable visualization markers
    enable_live_plots=True,                   # Enable live plots (auto-expands frames)
)

Newton Visualizer

Main Features:

• Lightweight OpenGL rendering with low overhead

• Visualization markers (joints, contacts, springs, COM)

• Training and rendering pause controls

• Adjustable update frequency for performance tuning

• Some customizable rendering options (shadows, sky, wireframe)

Interactive Controls:

Key/Input	Action
W, A, S, D or Arrow Keys	Forward / Left / Back / Right
Q, E	Down / Up
Left Click + Drag	Look around
Mouse Scroll	Zoom in/out
H	Toggle UI sidebar
ESC	Exit viewer

Core Configuration:

from isaaclab_visualizers.newton import NewtonVisualizerCfg

visualizer_cfg = NewtonVisualizerCfg(
    # Window settings
    window_width=1920,                        # Window width in pixels
    window_height=1080,                       # Window height in pixels

    # Camera settings
    camera_position=(8.0, 8.0, 3.0),         # Initial camera position (x, y, z)
    camera_target=(0.0, 0.0, 0.0),           # Camera look-at target

    # Performance tuning
    update_frequency=1,                       # Update every N frames (1=every frame)

    # Physics debug visualization
    show_joints=False,                        # Show joint visualizations
    show_contacts=False,                      # Show contact points and normals
    show_springs=False,                       # Show spring constraints
    show_com=False,                           # Show center of mass markers

    # Rendering options
    enable_shadows=True,                      # Enable shadow rendering
    enable_sky=True,                          # Enable sky rendering
    enable_wireframe=False,                   # Enable wireframe mode

    # Color customization
    background_color=(0.53, 0.81, 0.92),     # Sky/background color (RGB [0,1])
    ground_color=(0.18, 0.20, 0.25),         # Ground plane color (RGB [0,1])
    light_color=(1.0, 1.0, 1.0),             # Directional light color (RGB [0,1])
)

Rerun Visualizer

Main Features:

• Web viewer interface accessible from local or remote browser

• Metadata logging and filtering

• Recording to .rrd files for offline replay (.rrd files can be opened with ctrl+O from the web viewer)

• Timeline scrubbing and playback controls of recordings

Core Configuration:

from isaaclab_visualizers.rerun import RerunVisualizerCfg

visualizer_cfg = RerunVisualizerCfg(
    # Server settings
    app_id="isaaclab-simulation",             # Application identifier for viewer
    grpc_port=9876,                           # gRPC endpoint for logging SDK connection
    web_port=9090,                            # Port for local web viewer (launched in browser)
    bind_address="0.0.0.0",                  # Endpoint host formatting/reuse checks

    # Camera settings
    camera_position=(8.0, 8.0, 3.0),         # Initial camera position (x, y, z)
    camera_target=(0.0, 0.0, 0.0),           # Camera look-at target

    # History settings
    keep_historical_data=False,               # Keep transforms for time scrubbing
    keep_scalar_history=False,                # Keep scalar/plot history

    # Recording
    record_to_rrd="recording.rrd",            # Path to save .rrd file (None = no recording)
)

Rerun startup uses the Python SDK through newton.viewer.ViewerRerun (no external rerun CLI process management). If grpc_port is already active, Isaac Lab reuses that server. If web_port is occupied while starting a new server, initialization fails with a clear port-conflict error.

Viser Visualizer

The Viser visualizer provides a web-based 3D viewer for Isaac Lab simulations powered by the Newton Warp renderer. It streams the simulation state to a local web server, allowing you to view and interact with the scene from any browser.

Key features:

• Browser-based visualization accessible at http://localhost:8080 by default

• Optional public share URL for remote viewing

• Recording to .viser format for replay

• Environment filtering to control which environments are rendered

Launch with Viser:

./isaaclab.sh -p source/isaaclab_tasks/isaaclab_tasks/direct/cartpole/cartpole_env.py --viz viser

Configuration example:

from isaaclab_visualizers.viser import ViserVisualizerCfg

visualizer_cfg = ViserVisualizerCfg(
    port=8080,
    open_browser=True,
    label="Isaac Lab Simulation",
    share=False,
    max_worlds=64,
)

Configuration options:

• port (int, default 8080): Port of the local Viser web server.

• open_browser (bool, default True): Automatically open the viewer URL in a browser.

• label (str or None, default "Isaac Lab Simulation"): Page title shown in the viewer.

• share (bool, default False): Request a public share URL from Viser for remote viewing.

• record_to_viser (str or None, default None): Path to save a .viser recording file.

• verbose (bool, default True): Print viewer server startup information.

• max_worlds (int or None, default None): Maximum number of environments rendered.

Note

The Viser visualizer does not currently support markers or live plots.

Performance Note

To reduce overhead when visualizing large-scale environments, consider:

• Using Newton instead of Omniverse or Rerun

• Reducing window sizes

• Lower update frequencies

• Pausing visualizers while they are not being used

Limitations

Rerun Visualizer Performance

The Rerun web-based visualizer may experience performance issues or crashes when visualizing large-scale environments. For large-scale simulations, the Newton visualizer is recommended. Alternatively, to reduce load, the num of environments can be overwritten and decreased using --num_envs:

python scripts/reinforcement_learning/rsl_rl/train.py --task Isaac-Cartpole-v0 --viz rerun --num_envs 512

Note

A future feature will support visualizing only a subset of environments, which will improve visualization performance and reduce resource usage while maintaining full-scale training in the background.

Rerun Visualizer FPS Control

The FPS control in the Rerun visualizer UI may not affect the visualization frame rate in all configurations.

Newton Visualizer Contact and Center of Mass Markers

Contact and center of mass markers are not yet supported in the Newton visualizer. This will be addressed in a future release.

Viser Visualizer Markers and Live Plots

The Viser visualizer does not currently support visualization markers or live plots. For these features, use the Omniverse or Newton visualizers.

Viser Visualizer Renderer Requirement

The Viser visualizer requires a Newton model, which is provided automatically by SceneDataProvider regardless of the active physics backend or renderer. It is compatible with all rendering backends (RTX, Newton Warp, OVRTX).

Newton Visualizer CUDA/OpenGL Interoperability Warnings

On some system configurations, the Newton visualizer may display warnings about CUDA/OpenGL interoperability:

Warning: Could not get MSAA config, falling back to non-AA.
Warp CUDA error 999: unknown error (in function wp_cuda_graphics_register_gl_buffer)
Warp UserWarning: Could not register GL buffer since CUDA/OpenGL interoperability
is not available. Falling back to copy operations between the Warp array and the
OpenGL buffer.

The visualizer will still function correctly but may experience reduced performance due to falling back to CPU copy operations instead of direct GPU memory sharing.

Newton Visualizer on Spark with Conda

When running the Newton visualizer on Spark inside a conda environment, conda-installed X11 libraries may conflict with the system libraries required by pyglet, causing the following error:

pyglet.window.xlib.XlibException: Could not create UTF8 text property

To resolve this, remove the conflicting conda packages so that the system-provided libraries are used instead:

conda remove --force xorg-libx11 libxcb

See Also

• Renderers — renderer backends (RTX, Newton Warp, OVRTX)

• Scene Data Providers — how scene data flows from physics to visualizers

• Newton Physics Integration — Newton physics integration guide

• Migrating to Isaac Lab 3.0 — migration guide with --headless deprecation details