Archetype: A schema definition that describes the structure of messages in an MCAP file. More...

#include <rerun/archetypes/mcap_schema.hpp>

Public Member Functions
	McapSchema (McapSchema &&other)=default

	McapSchema (const McapSchema &other)=default

McapSchema &	operator= (const McapSchema &other)=default

McapSchema &	operator= (McapSchema &&other)=default

	McapSchema (rerun::components::SchemaId _id, rerun::components::Text _name, rerun::components::Text _encoding, rerun::components::Blob _data)

McapSchema	with_id (const rerun::components::SchemaId &_id) &&
	Unique identifier for this schema within the MCAP file.

McapSchema	with_many_id (const Collection< rerun::components::SchemaId > &_id) &&
	This method makes it possible to pack multiple `id` in a single component batch.

McapSchema	with_name (const rerun::components::Text &_name) &&
	Human-readable name identifying this schema.

McapSchema	with_many_name (const Collection< rerun::components::Text > &_name) &&
	This method makes it possible to pack multiple `name` in a single component batch.

McapSchema	with_encoding (const rerun::components::Text &_encoding) &&
	The schema definition format used to describe the message structure.

McapSchema	with_many_encoding (const Collection< rerun::components::Text > &_encoding) &&
	This method makes it possible to pack multiple `encoding` in a single component batch.

McapSchema	with_data (const rerun::components::Blob &_data) &&
	The schema definition content as binary data.

McapSchema	with_many_data (const Collection< rerun::components::Blob > &_data) &&
	This method makes it possible to pack multiple `data` in a single component batch.

Collection< ComponentColumn >	columns (const Collection< uint32_t > &lengths_)
	Partitions the component data into multiple sub-batches.

Collection< ComponentColumn >	columns ()
	Partitions the component data into unit-length sub-batches.

Static Public Member Functions
static McapSchema	update_fields ()
	Update only some specific fields of a `McapSchema`.

static McapSchema	clear_fields ()
	Clear all the fields of a `McapSchema`.

Public Attributes
std::optional< ComponentBatch >	id
	Unique identifier for this schema within the MCAP file.

std::optional< ComponentBatch >	name
	Human-readable name identifying this schema.

std::optional< ComponentBatch >	encoding
	The schema definition format used to describe the message structure.

std::optional< ComponentBatch >	data
	The schema definition content as binary data.

Static Public Attributes
static constexpr const char	ArchetypeName [] = "rerun.archetypes.McapSchema"
	The name of the archetype as used in `ComponentDescriptor`s.

static constexpr auto	Descriptor_id
	`ComponentDescriptor` for the `id` field.

static constexpr auto	Descriptor_name
	`ComponentDescriptor` for the `name` field.

static constexpr auto	Descriptor_encoding
	`ComponentDescriptor` for the `encoding` field.

static constexpr auto	Descriptor_data
	`ComponentDescriptor` for the `data` field.

Detailed Description

Archetype: A schema definition that describes the structure of messages in an MCAP file.

Schemas define the data types and field structures used by messages in MCAP channels. They provide the blueprint for interpreting message payloads, specifying field names, types, and organization. Each schema is referenced by channels to indicate how their messages should be decoded and understood.

See also archetypes::McapChannel for channels that reference these schemas, archetypes::McapMessage for the messages that conform to these schemas, and the MCAP specification for complete format details.

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

Member Function Documentation

◆ with_id()

McapSchema rerun::archetypes::McapSchema::with_id ( const rerun::components::SchemaId & _id ) &&

inline

Unique identifier for this schema within the MCAP file.

Schema IDs must be unique within an MCAP file and are referenced by channels to specify their message structure. A single schema can be shared across multiple channels.

◆ with_many_id()

McapSchema rerun::archetypes::McapSchema::with_many_id ( const Collection< rerun::components::SchemaId > & _id ) &&

inline

This method makes it possible to pack multiple id in a single component batch.

This only makes sense when used in conjunction with columns. with_id should be used when logging a single row's worth of data.

◆ with_name()

McapSchema rerun::archetypes::McapSchema::with_name ( const rerun::components::Text & _name ) &&

inline

Human-readable name identifying this schema.

Schema names typically describe the message type or data structure (e.g., "geometry_msgs/msg/Twist", "sensor_msgs/msg/Image", "MyCustomMessage").

◆ with_many_name()

McapSchema rerun::archetypes::McapSchema::with_many_name ( const Collection< rerun::components::Text > & _name ) &&

inline

This method makes it possible to pack multiple name in a single component batch.

This only makes sense when used in conjunction with columns. with_name should be used when logging a single row's worth of data.

◆ with_encoding()

McapSchema rerun::archetypes::McapSchema::with_encoding ( const rerun::components::Text & _encoding ) &&

inline

The schema definition format used to describe the message structure.

Common schema encodings include:

protobuf - Protocol Buffers schema definition
ros1msg - ROS1 message definition format
ros2msg - ROS2 message definition format
jsonschema - JSON Schema specification
flatbuffer - FlatBuffers schema definition

◆ with_many_encoding()

McapSchema rerun::archetypes::McapSchema::with_many_encoding ( const Collection< rerun::components::Text > & _encoding ) &&

inline

This method makes it possible to pack multiple encoding in a single component batch.

This only makes sense when used in conjunction with columns. with_encoding should be used when logging a single row's worth of data.

◆ with_data()

McapSchema rerun::archetypes::McapSchema::with_data ( const rerun::components::Blob & _data ) &&

inline

The schema definition content as binary data.

This contains the actual schema specification in the format indicated by the encoding field. For text-based schemas (like ROS message definitions or JSON Schema), this is typically UTF-8 encoded text. For binary schema formats, this contains the serialized schema data.

◆ with_many_data()

McapSchema rerun::archetypes::McapSchema::with_many_data ( const Collection< rerun::components::Blob > & _data ) &&

inline

This method makes it possible to pack multiple data in a single component batch.

This only makes sense when used in conjunction with columns. with_data should be used when logging a single row's worth of data.

◆ columns() [1/2]

Collection< ComponentColumn > rerun::archetypes::McapSchema::columns ( const Collection< uint32_t > & lengths_ )

Partitions the component data into multiple sub-batches.

Specifically, this transforms the existing ComponentBatch data into ComponentColumns instead, via ComponentBatch::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.

◆ columns() [2/2]

Collection< ComponentColumn > rerun::archetypes::McapSchema::columns ( )

Partitions the component data into unit-length sub-batches.

This is semantically similar to calling columns with std::vector<uint32_t>(n, 1), where n is automatically guessed.

Member Data Documentation

◆ id

std::optional<ComponentBatch> rerun::archetypes::McapSchema::id

Unique identifier for this schema within the MCAP file.

Schema IDs must be unique within an MCAP file and are referenced by channels to specify their message structure. A single schema can be shared across multiple channels.

◆ name

std::optional<ComponentBatch> rerun::archetypes::McapSchema::name

Human-readable name identifying this schema.

Schema names typically describe the message type or data structure (e.g., "geometry_msgs/msg/Twist", "sensor_msgs/msg/Image", "MyCustomMessage").

◆ encoding

std::optional<ComponentBatch> rerun::archetypes::McapSchema::encoding

The schema definition format used to describe the message structure.

Common schema encodings include:

protobuf - Protocol Buffers schema definition
ros1msg - ROS1 message definition format
ros2msg - ROS2 message definition format
jsonschema - JSON Schema specification
flatbuffer - FlatBuffers schema definition

◆ data

std::optional<ComponentBatch> rerun::archetypes::McapSchema::data

The schema definition content as binary data.

This contains the actual schema specification in the format indicated by the encoding field. For text-based schemas (like ROS message definitions or JSON Schema), this is typically UTF-8 encoded text. For binary schema formats, this contains the serialized schema data.

◆ Descriptor_id

constexpr auto rerun::archetypes::McapSchema::Descriptor_id

staticconstexpr

Initial value:

= ComponentDescriptor(
            ArchetypeName, "McapSchema:id", Loggable<rerun::components::SchemaId>::ComponentType
        )

ComponentDescriptor for the id field.

◆ Descriptor_name

constexpr auto rerun::archetypes::McapSchema::Descriptor_name

staticconstexpr

Initial value:

= ComponentDescriptor(
            ArchetypeName, "McapSchema:name", Loggable<rerun::components::Text>::ComponentType
        )

ComponentDescriptor for the name field.

◆ Descriptor_encoding

constexpr auto rerun::archetypes::McapSchema::Descriptor_encoding

staticconstexpr

Initial value:

= ComponentDescriptor(
            ArchetypeName, "McapSchema:encoding", Loggable<rerun::components::Text>::ComponentType
        )

ComponentDescriptor for the encoding field.

◆ Descriptor_data

constexpr auto rerun::archetypes::McapSchema::Descriptor_data

staticconstexpr

Initial value:

= ComponentDescriptor(
            ArchetypeName, "McapSchema:data", Loggable<rerun::components::Blob>::ComponentType
        )

ComponentDescriptor for the data field.

The documentation for this struct was generated from the following file:

rerun/archetypes/mcap_schema.hpp

Public Member Functions

Static Public Member Functions

Public Attributes

Static Public Attributes

Detailed Description

Member Function Documentation

◆ with_id()

◆ with_many_id()

◆ with_name()

◆ with_many_name()

◆ with_encoding()

◆ with_many_encoding()

◆ with_data()

◆ with_many_data()

◆ columns() [1/2]

◆ columns() [2/2]

Member Data Documentation

◆ id

◆ name

◆ encoding

◆ data

◆ Descriptor_id

◆ Descriptor_name

◆ Descriptor_encoding

◆ Descriptor_data