Event Functors

This page lists all available event functors that can be used with the Event Manager. Event functors are configured using EventCfg and can be triggered at different stages: startup, reset, or interval.

Physics Randomization

Physics Randomization Functors

Functor Name	Description
randomize_rigid_object_mass	Randomize object masses within a specified range. Supports both absolute and relative mass randomization.
randomize_rigid_object_center_of_mass	Randomize the center of mass of rigid objects by applying position offsets. Only works with dynamic objects.

Visual Randomization

Visual Randomization Functors

Functor Name	Description
randomize_visual_material	Randomize textures, base colors, and material properties (metallic, roughness, IOR). Implemented as a Functor class. Supports both RigidObject and Articulation assets.
randomize_light	Vary light position, color, and intensity within specified ranges.
randomize_emission_light	Randomize global emission light color and intensity. Applies the same emission light properties across all environments.
randomize_camera_extrinsics	Randomize camera poses for viewpoint diversity. Supports both attach mode (pos/euler perturbation) and look_at mode (eye/target/up perturbation).
randomize_camera_intrinsics	Vary focal length (fx, fy) and principal point (cx, cy) within specified ranges.
set_rigid_object_visual_material	Set a rigid object’s visual material deterministically (non-random). Useful for configs that want fixed colors/materials during reset.
set_rigid_object_group_visual_material	Set a rigid object group’s visual material deterministically (non-random). Useful for configs that want fixed colors/materials during reset.

Spatial Randomization

Spatial Randomization Functors

Functor Name	Description
randomize_rigid_object_pose	Randomize object positions and orientations. Supports both relative and absolute pose randomization.
randomize_robot_eef_pose	Vary end-effector initial poses by solving inverse kinematics. The randomization is performed relative to the current end-effector pose.
randomize_robot_qpos	Randomize robot joint configurations. Supports both relative and absolute joint position randomization, and can target specific joints.
randomize_target_pose	Randomize a virtual target pose and store it in env state. Generates random target poses without requiring a physical object in the scene.
planner_grid_cell_sampler	Sample grid cells for object placement without replacement. Implemented as a Functor class. Divides a planar region into a regular 2D grid and samples cells to place objects at their centers.

Geometry Randomization

Geometry Randomization Functors

Functor Name	Description
randomize_rigid_object_scale	Randomize a rigid object’s body scale factors (multiplicative). Supports uniform scaling across all axes or independent per-axis scaling.
randomize_rigid_objects_scale	Randomize body scale factors for multiple rigid objects. Supports shared sampling (same scale for all objects) or independent sampling per object.

Asset Management

Asset Management Functors

Functor Name	Description
replace_assets_from_group	Swap object models from a folder on reset for visual diversity. Currently supports RigidObject assets with mesh-based shapes.
prepare_extra_attr	Set up additional object attributes dynamically. Supports both static values and callable functions. Useful for setting up affordance data and other custom attributes.
register_entity_attrs	Register entity attributes to a registration dict in the environment. Supports fetching attributes from both entity properties and prepare_extra_attr functor.
register_entity_pose	Register entity poses to a registration dict. Supports computing relative poses between entities and transforming object-frame poses to arena frame.
register_info_to_env	Batch register multiple entity attributes and poses using a registry list. Combines register_entity_attrs and register_entity_pose functionality.
drop_rigid_object_group_sequentially	Drop objects from a rigid object group one by one from a specified height with position randomization.
set_detached_uids_for_env_reset	Set UIDs of objects that should be detached from automatic reset. Useful for objects that need custom reset handling.

Usage Example

from embodichain.lab.gym.envs.managers.cfg import EventCfg, SceneEntityCfg

# Example: Randomize object mass on reset
events = {
    "randomize_mass": EventCfg(
        func="randomize_rigid_object_mass",
        mode="reset",
        params={
            "entity_cfg": SceneEntityCfg(uid="cube"),
            "mass_range": (0.1, 2.0),
            "relative": False,
        },
    ),
}