snapshot Namespace Reference

Snapshot serialization/deserialization utilities for networked state synchronization. More...

Functions
void	write_string (std::vector< uint8_t > &out, const std::string &str)
	Writes a length-prefixed string to a binary buffer.
bool	read_string (const std::vector< uint8_t > &data, size_t &offset, std::string &out)
	Reads a length-prefixed string from a binary buffer.
void	write_bytes (std::vector< uint8_t > &out, const void *data, size_t size)
	Writes raw bytes to a binary buffer.
bool	read_bytes (const std::vector< uint8_t > &data, size_t &offset, void *out, size_t size)
	Reads raw bytes from a binary buffer.
Message	create_full_snapshot (const Scene &scene, DefaultMessageTypes messageType)
	Builds a full snapshot message containing all networked GameObjects in a scene.
Message	create_delta_snapshot (const Scene &scene, DefaultMessageTypes messageType)
	Builds a delta snapshot message containing only changed (dirty) networked objects.
void	apply_full_snapshot (Scene &scene, const Message &msg)
	Applies a full snapshot to a scene, creating/updating GameObjects as needed.
void	apply_delta_snapshot (Scene &scene, const Message &msg)
	Applies a delta snapshot to a scene, updating only the listed objects.

Detailed Description

Snapshot serialization/deserialization utilities for networked state synchronization.

These helpers provide a clean API for packing GameObject state into network messages and unpacking them on remote clients. The snapshot payloads are binary and compact: uint16_t count for each object: char uuid[37] float x, y, z (position)

The engine exposes creators for full snapshots and delta snapshots and corresponding apply helpers for clients.

Function Documentation

apply_delta_snapshot()

void snapshot::apply_delta_snapshot	(	Scene &	scene,
		const Message &	msg
	)

Applies a delta snapshot to a scene, updating only the listed objects.

This will update transforms for existing networked objects and create missing ones if necessary.

apply_full_snapshot()

void snapshot::apply_full_snapshot	(	Scene &	scene,
		const Message &	msg
	)

Applies a full snapshot to a scene, creating/updating GameObjects as needed.

For each object in the snapshot:

• If an object with matching NetworkIdentity UUID exists, updates its position.
• Otherwise, creates a new GameObject, attaches a NetworkIdentity, and applies the position.

Parameters

scene	Target scene to apply snapshot to.
msg	The snapshot message to deserialize.
spriteTexture	Name of the sprite texture to use for newly created objects.

create_delta_snapshot()

Message snapshot::create_delta_snapshot	(	const Scene &	scene,
		DefaultMessageTypes	messageType
	)

Builds a delta snapshot message containing only changed (dirty) networked objects.

Implementations should mark objects dirty (via their NetworkIdentity) when their relevant state changes. This function clears the dirty flag for included objects.

Parameters

scene	The scene to snapshot.
messageType	The message type to assign for delta snapshots.

Returns

A Message containing only changed objects since the last snapshot.

create_full_snapshot()

Message snapshot::create_full_snapshot	(	const Scene &	scene,
		DefaultMessageTypes	messageType
	)

Builds a full snapshot message containing all networked GameObjects in a scene.

Parameters

scene	The scene to snapshot.
messageType	The message type to assign (usually SNAPSHOT_FULL).

Returns

A Message ready to send, containing serialized GameObject state.

read_bytes()

bool snapshot::read_bytes	(	const std::vector< uint8_t > &	data,
		size_t &	offset,
		void *	out,
		size_t	size
	)

Reads raw bytes from a binary buffer.

Copies the specified number of bytes from the buffer. Advances the offset past the read data.

Parameters

data	Input buffer to read from.
offset	Current read position; updated to point past the bytes.
out	Output buffer to store the deserialized data.
size	Number of bytes to read.

Returns

true if read succeeded, false if buffer bounds exceeded.

read_string()

bool snapshot::read_string	(	const std::vector< uint8_t > &	data,
		size_t &	offset,
		std::string &	out
	)

Reads a length-prefixed string from a binary buffer.

Decodes a uint16_t length prefix and reads the corresponding string data. Advances the offset past the read data.

Parameters

data	Input buffer to read from.
offset	Current read position; updated to point past the string.
out	Output string to store the deserialized value.

Returns

true if read succeeded, false if buffer bounds exceeded.

write_bytes()

void snapshot::write_bytes	(	std::vector< uint8_t > &	out,
		const void *	data,
		size_t	size
	)

Writes raw bytes to a binary buffer.

Appends the specified data to the buffer without any encoding. Used for serializing fixed-size types (floats, ints, etc.).

Parameters

out	Output buffer to write to.
data	Pointer to data to serialize.
size	Number of bytes to write.

write_string()

void snapshot::write_string	(	std::vector< uint8_t > &	out,
		const std::string &	str
	)

Writes a length-prefixed string to a binary buffer.

Encodes the string length as a uint16_t followed by the string data. Used for compact serialization of variable-length strings.

Parameters

out	Output buffer to write to.
str	String to serialize.