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PYTHONPUBLIC API

fastsim.api.scene

Current public Python API for fastsim.api.scene; signatures are extracted directly from the vNext AST.

Public symbols 21

class

Pose

L327

class Pose(object)

One right-handed SI pose expressed in the explicitly named frame.

Field	Type	Default
frame_id	str	—
xyz_m	tuple[float, float, float]	—
quat_xyzw	tuple[float, float, float, float]	—

class

Twist

L356

class Twist(object)

Linear and angular velocity expressed in one explicitly named frame.

Field	Type	Default
frame_id	str	—
linear_m_s	tuple[float, float, float]	—
angular_rad_s	tuple[float, float, float]	—

class

EntityDescriptor

L370

class EntityDescriptor(object)

Path-free static facts for one compiled scene entity.

Field	Type	Default
entity_id	str	—
authored_name	str	—
kind	str	—
enabled	bool	—
component_identity	str	—
component_version	str	—
link_ids	tuple[str, ...]	()
frame_ids	tuple[str, ...]	()
geometry_ids	tuple[str, ...]	()
control_resource_groups	tuple[str, ...]	()

class

LinkDescriptor

L420

class LinkDescriptor(object)

Backend-neutral relationship facts for one articulation or rigid link.

Field	Type	Default
link_id	str	—
entity_id	str	—
authored_name	str	—
frame_id	str	—
parent_link_id	str \| None	None
geometry_ids	tuple[str, ...]	()

class

JointDescriptor

L450

class JointDescriptor(object)

One physical scalar articulation axis in declared execution order.

Field	Type	Default
joint_id	str	—
authored_name	str	—
parent_link_id	str	—
child_link_id	str	—
joint_type	str	—
axis_frame_id	str	—
axis_xyz	tuple[float, float, float]	—
position_unit	str	—
lower	float \| None	—
upper	float \| None	—
max_velocity	float \| None	None
max_effort	float \| None	None

class

ArticulationDescriptor

L507

class ArticulationDescriptor(object)

Ordered physical joint facts for any articulation, robot or otherwise.

Field	Type	Default
entity_id	str	—
joints	tuple[JointDescriptor, ...]	—

joint_ids

ArticulationDescriptor.joint_ids(self) -> tuple[str, ...]

Physical axis IDs in provider-declared order, never name-inferred.

joint_names

ArticulationDescriptor.joint_names(self) -> tuple[str, ...]

Authored physical joint names in provider-declared order.

class

SceneQuery

L542

class SceneQuery(object)

A bounded, deterministic intersection filter for scene reads.

Field	Type	Default
entity_ids	tuple[str, ...]	()
link_ids	tuple[str, ...]	()
kinds	tuple[str, ...]	()
enabled	bool \| None	None

class

SceneCatalogSnapshot

L566

class SceneCatalogSnapshot(object)

Immutable deterministic static scene projection for one generation.

Field	Type	Default
run_id	str	—
plan_digest	str	—
generation	int	—
catalog_revision	int	—
content_sha256	str	—
entities	tuple[EntityDescriptor, ...]	—
links	tuple[LinkDescriptor, ...]	—
articulations	tuple[ArticulationDescriptor, ...]	—

class

EntityState

L876

class EntityState(object)

Dynamic state of the entity asset-root frame. ``pose`` is the imported asset/model root pose. For USD backends this is the spawned entity Prim pose; articulation root-link poses are exposed only through :class:`LinkState`.

Field	Type	Default
entity_id	str	—
pose	Pose	—
twist	Twist	—

class

LinkState

L897

class LinkState(object)

No public docstring is provided in the current source.

Field	Type	Default
link_id	str	—
pose	Pose	—
twist	Twist	—

class

ArticulationState

L911

class ArticulationState(object)

Compact physical joint state in the descriptor's declared axis order.

Field	Type	Default
entity_id	str	—
joint_ids	tuple[str, ...]	—
positions	tuple[float, ...]	—
velocities	tuple[float, ...]	—
position_units	tuple[str, ...]	—
velocity_units	tuple[str, ...]	—

class

AttachmentState

L949

class AttachmentState(object)

One portable attachment relationship without a native constraint handle.

Field	Type	Default
attachment_id	str	—
parent_entity_id	str	—
child_entity_id	str	—
parent_frame_id	str	—
child_frame_id	str	—
parent_T_child	Pose	—
geometry_ids	tuple[str, ...]	—
parent_link_id	str \| None	None
child_link_id	str \| None	None

class

SceneStateSnapshot

L997

class SceneStateSnapshot(object)

Compact scene state committed atomically at exactly one authority tick.

Field	Type	Default
run_id	str	—
generation	int	—
sim_tick	int	—
sim_time_s	float	—
sequence	int	—
captured_monotonic_ns	int	—
world_revision	int	—
catalog_revision	int	—
catalog_content_sha256	str	—
attachment_revision	int	—
entity_states	tuple[EntityState, ...]	—
link_states	tuple[LinkState, ...]	—
articulation_states	tuple[ArticulationState, ...]	—
attachments	tuple[AttachmentState, ...]	—

class

SceneDeltaKind

L1062

class SceneDeltaKind(StrEnum)

No public docstring is provided in the current source.

class

SceneDelta

L1070

class SceneDelta(object)

One bounded scene change; no geometry payload is permitted by shape.

Field	Type	Default
run_id	str	—
generation	int	—
sim_tick	int	—
sim_time_s	float	—
sequence	int	—
captured_monotonic_ns	int	—
base_sequence	int	—
previous_world_revision	int	—
world_revision	int	—
previous_catalog_revision	int	—
catalog_revision	int	—
previous_catalog_content_sha256	str \| None	—
catalog_content_sha256	str \| None	—
previous_attachment_revision	int	—
attachment_revision	int	—
kind	SceneDeltaKind	—
added_entities	tuple[EntityDescriptor, ...]	()
removed_entity_ids	tuple[str, ...]	()
added_links	tuple[LinkDescriptor, ...]	()
removed_link_ids	tuple[str, ...]	()
added_articulations	tuple[ArticulationDescriptor, ...]	()
removed_articulation_entity_ids	tuple[str, ...]	()
entity_states	tuple[EntityState, ...]	()
link_states	tuple[LinkState, ...]	()
articulation_states	tuple[ArticulationState, ...]	()
attachments	tuple[AttachmentState, ...]	()
removed_attachment_ids	tuple[str, ...]	()
resync_required	bool	False

function

validate_scene_state_against

L1287

validate_scene_state_against(catalog: SceneCatalogSnapshot, state: SceneStateSnapshot) -> None

Validate one committed state against its exact scoped static catalog.

function

validate_scene_delta_against

L1364

validate_scene_delta_against(catalog: SceneCatalogSnapshot, state: SceneStateSnapshot, delta: SceneDelta) -> None

Validate a delta's base identity before a provider applies its payload.

class

SceneQueryErrorCode

L1398

class SceneQueryErrorCode(StrEnum)

No public docstring is provided in the current source.

class

SceneQueryError

L1407

class SceneQueryError(RuntimeError)

Typed bounded failure from ``fastsim.scene.query@3``.

class

SceneDeltaSubscription

L1440

class SceneDeltaSubscription(Protocol)

No public docstring is provided in the current source.

dropped

SceneDeltaSubscription.dropped(self) -> int

No public docstring is provided in the current source.

closed

SceneDeltaSubscription.closed(self) -> bool

No public docstring is provided in the current source.

get_async

async SceneDeltaSubscription.get_async(self, timeout: float | None=None) -> SceneDelta

No public docstring is provided in the current source.

SceneDeltaSubscription.close(self) -> None

No public docstring is provided in the current source.

class

SceneQueryService

L1453

class SceneQueryService(Protocol)

Capability-scoped read-only entity catalog and committed state.

service_id

SceneQueryService.service_id(self) -> str

No public docstring is provided in the current source.

catalog

SceneQueryService.catalog(self, query: SceneQuery | None=None) -> SceneCatalogSnapshot

No public docstring is provided in the current source.

state

SceneQueryService.state(self, query: SceneQuery | None=None) -> SceneStateSnapshot

No public docstring is provided in the current source.

SceneQueryService.subscribe(self, query: SceneQuery | None=None, capacity: int=16) -> SceneDeltaSubscription

No public docstring is provided in the current source.