Struct StateChange 

pub struct StateChange {
    pub state: Option<SerializedComponentBatch>,
}

Archetype: A state change, representing a transition of an entity into a new state.

Useful for representing discrete state machines, mode transitions, or state changes over time. Each logged archetypes::StateChange marks a new state at the given time. A null state is ignored by the state timeline view.

The state timeline view displays these as horizontal colored lanes over time.

⚠️ This type is unstable and may change significantly in a way that the data won’t be backwards compatible.

Example

State changes over time

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let rec = rerun::RecordingStreamBuilder::new("rerun_example_state_change")
        .spawn()?;

    rec.set_time_sequence("step", 0);
    rec.log("door", &rerun::StateChange::new().with_state("open"))?;

    rec.set_time_sequence("step", 1);
    rec.log("door", &rerun::StateChange::new().with_state("closed"))?;

    rec.set_time_sequence("step", 2);
    rec.log("door", &rerun::StateChange::new().with_state("open"))?;

    Ok(())
}

Fields

state: Option<SerializedComponentBatch>

The new state value.

A null state is ignored, it can be used to partially update a multi-instance state array. An empty string is treated as state reset, and a gap is shown in the state timeline view.

Implementations

impl StateChange

pub fn descriptor_state() -> ComponentDescriptor

Returns the ComponentDescriptor for Self::state.

The corresponding component is crate::components::Text.

impl StateChange

pub const NUM_COMPONENTS: usize = 1usize

The total number of components in the archetype: 1 required, 0 recommended, 0 optional

impl StateChange

pub fn new() -> StateChange

Create a new StateChange.

pub fn update_fields() -> StateChange

Update only some specific fields of a StateChange.

pub fn clear_fields() -> StateChange

Clear all the fields of a StateChange.

pub fn columns<I>( self, _lengths: I, ) -> Result<impl Iterator<Item = SerializedComponentColumn>, SerializationError>

where I: IntoIterator<Item = usize> + Clone,

Partitions the component data into multiple sub-batches.

Specifically, this transforms the existing SerializedComponentBatches data into SerializedComponentColumns instead, via SerializedComponentBatch::partitioned.

This makes it possible to use RecordingStream::send_columns to send columnar data directly into Rerun.

The specified lengths must sum to the total length of the component batch.

pub fn columns_of_unit_batches( self, ) -> Result<impl Iterator<Item = SerializedComponentColumn>, SerializationError>

Helper to partition the component data into unit-length sub-batches.

This is semantically similar to calling Self::columns with std::iter::take(1).repeat(n), where n is automatically guessed.

pub fn with_state(self, state: impl Into<Text>) -> StateChange

The new state value.

A null state is ignored, it can be used to partially update a multi-instance state array. An empty string is treated as state reset, and a gap is shown in the state timeline view.

pub fn with_many_state( self, state: impl IntoIterator<Item = impl Into<Text>>, ) -> StateChange

This method makes it possible to pack multiple crate::components::Text in a single component batch.

This only makes sense when used in conjunction with Self::columns. Self::with_state should be used when logging a single row’s worth of data.

Trait Implementations

impl Archetype for StateChange

fn name() -> ArchetypeName

The fully-qualified name of this archetype, e.g. rerun.archetypes.Points2D.

fn display_name() -> &'static str

Readable name for displaying in UI.

fn required_components() -> Cow<'static, [ComponentDescriptor]>

Returns all component descriptors that must be provided by the user when constructing this archetype.

fn recommended_components() -> Cow<'static, [ComponentDescriptor]>

Returns all component descriptors that should be provided by the user when constructing this archetype.

fn optional_components() -> Cow<'static, [ComponentDescriptor]>

Returns all component descriptors that may be provided by the user when constructing this archetype.

fn all_components() -> Cow<'static, [ComponentDescriptor]>

Returns all component descriptors that must, should and may be provided by the user when constructing this archetype.

fn from_arrow_components( arrow_data: impl IntoIterator<Item = (ComponentDescriptor, Arc<dyn Array>)>, ) -> Result<StateChange, DeserializationError>

Given an iterator of Arrow arrays and their respective ComponentDescriptors, deserializes them into this archetype.

fn all_component_identifiers() -> impl Iterator<Item = ComponentIdentifier>

Utility method based on Self::all_components to return all component identifiers.

fn from_arrow( data: impl IntoIterator<Item = (Field, Arc<dyn Array>)>, ) -> Result<Self, DeserializationError>

where Self: Sized,

Given an iterator of Arrow arrays and their respective field metadata, deserializes them into this archetype.

impl AsComponents for StateChange

fn as_serialized_batches(&self) -> Vec<SerializedComponentBatch>

Exposes the object’s contents as a set of SerializedComponentBatches.

fn to_arrow(&self) -> Result<Vec<(Field, Arc<dyn Array>)>, SerializationError>

Serializes all non-null Components of this bundle into Arrow arrays.

impl Clone for StateChange

fn clone(&self) -> StateChange

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for StateChange

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for StateChange

fn default() -> StateChange

Returns the “default value” for a type.

impl PartialEq for StateChange

fn eq(&self, other: &StateChange) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl SizeBytes for StateChange

fn heap_size_bytes(&self) -> u64

Returns how many bytes self uses on the heap.

fn total_size_bytes(&self) -> u64

Returns the total size of self in bytes, accounting for both stack and heap space.

fn stack_size_bytes(&self) -> u64

Returns the total size of self on the stack, in bytes.

fn is_pod() -> bool

where Self: Sized,

Is Self just plain old data?

impl VisualizableArchetype for StateChange

fn visualizer(&self) -> Visualizer

Create a visualizer for this archetype, using all currently set values as overrides.

impl ArchetypeReflectionMarker for StateChange

impl StructuralPartialEq for StateChange