LightBeamSensor

Fully qualified name: isaacsim::sensors::physx::LightBeamSensor

class LightBeamSensor : public isaacsim::sensors::physx::RangeSensorComponentBase<PrimType>

A sensor that simulates a curtain of light beams for range detection.

This sensor projects multiple light beams in a curtain pattern to detect objects and measure distances. It is useful for applications like safety curtains, area monitoring, and object detection along a plane. The sensor uses PhysX ray casting to detect intersections with objects and provides hit status, depth measurements, and hit positions for each beam.

Public Functions

LightBeamSensor(omni::physx::IPhysx *physXInterface)

Constructs a new Light Beam Sensor instance.

Parameters:

physXInterface – [in] Pointer to the PhysX interface for physics simulation

virtual ~LightBeamSensor() = default

Virtual destructor for proper cleanup.

virtual void onStart()

Initializes the light beam sensor when the component starts.

Sets up initial parameters, allocates memory for beam data, and prepares the sensor for operation

inline virtual void preTick()

Performs pre-tick operations before the main sensor update.

Empty implementation as no pre-tick operations are needed

inline virtual void tick()

Performs the main sensor update during each tick.

Empty implementation as updates are handled in onPhysicsStep

inline virtual void onStop()

Cleans up resources when the component stops.

Empty implementation as no specific cleanup is needed

virtual void onPhysicsStep()

Updates sensor data during physics simulation steps.

Performs ray casting and updates beam hit data based on the current physics state

virtual void onComponentChange()

Handles component property changes.

Updates sensor configuration when properties are modified through the interface

inline int getNumRays() const

Gets the number of rays in the light curtain.

Returns:

Number of individual light beams

inline std::vector<uint8_t> &getBeamHitData()

Gets the hit status for each beam.

Returns:

Reference to vector containing hit flags (0 for no hit, 1 for hit)

inline std::vector<float> &getLinearDepthData()

Gets the linear depth measurements for each beam.

Returns:

Reference to vector containing depth values in meters

inline std::vector<carb::Float3> &getHitPosData()

Gets the hit positions for each beam.

Returns:

Reference to vector containing 3D hit positions

inline void getTransformData(

omni::math::linalg::matrix4d &matrixOutput,

)

Gets the current transform of the sensor.

Parameters:

matrixOutput – [out] Output matrix containing the sensor’s position and orientation

inline std::vector<carb::Float3> &getBeamOrigins()

Gets the origin points of all beams.

Returns:

Reference to vector containing 3D beam origin positions

inline std::vector<carb::Float3> &getBeamEndPoints()

Gets the end points of all beams.

Returns:

Reference to vector containing 3D beam end positions

inline virtual void initialize(

const PrimType &prim,

pxr::UsdStageWeakPtr stage,

)

Initializes various pointers and handles in the component.

Must be called after creation, can be overridden to initialize subcomponents

Parameters:

• prim – [in] The USD prim representing this sensor

• stage – [in] The USD stage containing the sensor prim

inline virtual void onPhysicsStep(float dt)

Called during each physics simulation step.

Override this to implement physics-based behavior

Parameters:

dt – [in] Time step size in seconds

inline virtual void draw()

Called after all sensors have simulated to perform any drawing related tasks.

Renders the debug visualization for both points and lines if enabled

inline virtual void updateTimestamp(

double timeSeconds,

double dt,

int64_t timeNano,

)

Updates timestamps for component.

Parameters:

• timeSeconds – [in] Current simulation time in seconds

• dt – [in] Time step duration in seconds

• timeNano – [in] Current simulation time in nanoseconds

inline bool getDrawPoints()

Gets the draw points visualization state.

Returns:

True if point visualization is enabled, false otherwise

inline bool getDrawLines()

Gets the draw lines visualization state.

Returns:

True if line visualization is enabled, false otherwise

inline std::vector<carb::Float3> &getPointCloud()

Gets the latest point cloud data from the range sensor.

Returns a reference to the vector containing the most recent hit positions detected by the range sensor. Each point represents a detected surface in 3D space.

Returns:

Reference to vector of 3D points representing the latest point cloud data

inline virtual void onRenderEvent()

Called for each rendered frame.

Override this to implement render-specific behavior or visual updates

inline PrimType &getPrim()

Retrieves the component’s USD prim.

Returns:

Reference to the component’s USD prim

inline bool getEnabled()

Checks if the component is enabled.

Returns:

true if the component is enabled, false otherwise

inline uint64_t getSequenceNumber()

Gets the component’s sequence number.

Returns:

The component’s sequence number

Public Members

bool mDoStart = true

Flag indicating whether onStart should be called.

Protected Attributes

bool m_drawPoints = false

Flag to enable/disable point visualization.

bool m_drawLines = false

Flag to enable/disable line visualization.

std::vector<carb::Float3> m_lastHitPos

Vector storing the most recent hit positions from the sensor.

float m_minRange = 0.4f

Minimum range of the sensor in meters.

float m_maxRange = 100.0f

Maximum range of the sensor in meters.

float m_metersPerUnit = 1.0

Conversion factor from scene units to meters.

pxr::UsdPrim m_parentPrim

Reference to the parent USD prim containing this sensor.

omni::physx::IPhysx *m_physx = nullptr

Pointer to the PhysX interface.

::physx::PxScene *m_pxScene = nullptr

Pointer to the PhysX scene.

omni::timeline::ITimeline *m_timeline = nullptr

Pointer to the timeline interface.

omni::fabric::IToken *m_token = nullptr

Pointer to the fabric token interface.

carb::tasking::ITasking *m_tasking = nullptr

Pointer to the tasking interface.

std::shared_ptr<isaacsim::util::debug_draw::drawing::PrimitiveDrawingHelper> m_lineDrawing

Helper for drawing debug lines.

std::shared_ptr<isaacsim::util::debug_draw::drawing::PrimitiveDrawingHelper> m_pointDrawing

Helper for drawing debug points.

pxr::RangeSensorRangeSensor m_rangeSensorPrim

Reference to the range sensor USD prim.

pxr::UsdTimeCode m_parentPrimTimeCode

Time code for the parent prim’s current state.

bool m_isParentPrimTimeSampled = false

Flag indicating if the parent prim has time-sampled transforms.

bool m_firstFrame = true

Flag indicating if this is the first frame.

PrimType m_prim

USD prim reference storing component settings.

pxr::UsdStageWeakPtr m_stage = nullptr

Weak pointer to the USD stage containing the prim.

usdrt::UsdStageRefPtr m_usdrtStage = nullptr

Runtime USD stage reference.

double m_timeSeconds = 0

Current simulation time in seconds.

int64_t m_timeNanoSeconds = 0

Current simulation time in nanoseconds.

double m_timeDelta = 0

Time delta for current tick in seconds.

uint64_t m_sequenceNumber = 0

Component sequence number for ordering/identification.

bool m_enabled = true

Component enabled state flag.