ENetConnection

Inherits: RefCounted < Object

A wrapper class for an ENetHost.

Description

ENet's purpose is to provide a relatively thin, simple and robust network communication layer on top of UDP (User Datagram Protocol).

Methods

void

bandwidth_limit ( int in_bandwidth=0, int out_bandwidth=0 )

void

broadcast ( int channel, PackedByteArray packet, int flags )

void

channel_limit ( int limit )

void

compress ( CompressionMode mode )

ENetPacketPeer

connect_to_host ( String address, int port, int channels=0, int data=0 )

Error

create_host ( int max_peers=32, int max_channels=0, int in_bandwidth=0, int out_bandwidth=0 )

Error

create_host_bound ( String bind_address, int bind_port, int max_peers=32, int max_channels=0, int in_bandwidth=0, int out_bandwidth=0 )

void

destroy ( )

Error

dtls_client_setup ( X509Certificate certificate, String hostname, bool verify=true )

Error

dtls_server_setup ( CryptoKey key, X509Certificate certificate )

void

flush ( )

int

get_local_port ( ) const

int

get_max_channels ( ) const

Array

get_peers ( )

float

pop_statistic ( HostStatistic statistic )

void

refuse_new_connections ( bool refuse )

Array

service ( int timeout=0 )

Enumerations

enum CompressionMode:

  • COMPRESS_NONE = 0 --- No compression. This uses the most bandwidth, but has the upside of requiring the fewest CPU resources. This option may also be used to make network debugging using tools like Wireshark easier.

  • COMPRESS_RANGE_CODER = 1 --- ENet's built-in range encoding. Works well on small packets, but is not the most efficient algorithm on packets larger than 4 KB.

  • COMPRESS_FASTLZ = 2 --- FastLZ compression. This option uses less CPU resources compared to COMPRESS_ZLIB, at the expense of using more bandwidth.

  • COMPRESS_ZLIB = 3 --- Zlib compression. This option uses less bandwidth compared to COMPRESS_FASTLZ, at the expense of using more CPU resources.

  • COMPRESS_ZSTD = 4 --- Zstandard compression. Note that this algorithm is not very efficient on packets smaller than 4 KB. Therefore, it's recommended to use other compression algorithms in most cases.


enum EventType:

  • EVENT_ERROR = -1 --- An error occurred during service. You will likely need to destroy the host and recreate it.

  • EVENT_NONE = 0 --- No event occurred within the specified time limit.

  • EVENT_CONNECT = 1 --- A connection request initiated by enet_host_connect has completed. The array will contain the peer which successfully connected.

  • EVENT_DISCONNECT = 2 --- A peer has disconnected. This event is generated on a successful completion of a disconnect initiated by ENetPacketPeer.peer_disconnect, if a peer has timed out, or if a connection request intialized by connect_to_host has timed out. The array will contain the peer which disconnected. The data field contains user supplied data describing the disconnection, or 0, if none is available.

  • EVENT_RECEIVE = 3 --- A packet has been received from a peer. The array will contain the peer which sent the packet, the channel number upon which the packet was received, and the received packet.


enum HostStatistic:

  • HOST_TOTAL_SENT_DATA = 0 --- Total data sent.

  • HOST_TOTAL_SENT_PACKETS = 1 --- Total UDP packets sent.

  • HOST_TOTAL_RECEIVED_DATA = 2 --- Total data received.

  • HOST_TOTAL_RECEIVED_PACKETS = 3 --- Total UDP packets received.

Method Descriptions

  • void bandwidth_limit ( int in_bandwidth=0, int out_bandwidth=0 )

Adjusts the bandwidth limits of a host.


Queues a packet to be sent to all peers associated with the host over the specified channel. See ENetPacketPeer FLAG_* constants for available packet flags.


  • void channel_limit ( int limit )

Limits the maximum allowed channels of future incoming connections.


Sets the compression method used for network packets. These have different tradeoffs of compression speed versus bandwidth, you may need to test which one works best for your use case if you use compression at all.

Note: Most games' network design involve sending many small packets frequently (smaller than 4 KB each). If in doubt, it is recommended to keep the default compression algorithm as it works best on these small packets.

Note: The compression mode must be set to the same value on both the server and all its clients. Clients will fail to connect if the compression mode set on the client differs from the one set on the server.


Initiates a connection to a foreign address using the specified port and allocting the requested channels. Optional data can be passed during connection in the form of a 32 bit integer.

Note: You must call either create_host or create_host_bound before calling this method.


  • Error create_host ( int max_peers=32, int max_channels=0, int in_bandwidth=0, int out_bandwidth=0 )

Create an ENetHost that will allow up to max_peers connected peers, each allocating up to max_channels channels, optionally limiting bandwith to in_bandwidth and out_bandwidth.


  • Error create_host_bound ( String bind_address, int bind_port, int max_peers=32, int max_channels=0, int in_bandwidth=0, int out_bandwidth=0 )

Create an ENetHost like create_host which is also bound to the given bind_address and bind_port.


  • void destroy ( )

Destroys the host and all resources associated with it.


Configure this ENetHost to use the custom Godot extension allowing DTLS encryption for ENet clients. Call this before connect_to_host to have ENet connect using DTLS with certificate and hostname verification. Verification can be optionally turned off via the verify parameter.


Configure this ENetHost to use the custom Godot extension allowing DTLS encryption for ENet servers. Call this right after create_host_bound to have ENet expect peers to connect using DTLS.


  • void flush ( )

Sends any queued packets on the host specified to its designated peers.


  • int get_local_port ( ) const

Returns the local port to which this peer is bound.


  • int get_max_channels ( ) const

Returns the maximum number of channels allowed for connected peers.


Returns the list of peers associated with this host.

Note: This list might include some peers that are not fully connected or are still being disconnected.


Returns and resets host statistics. See HostStatistic for more info.


  • void refuse_new_connections ( bool refuse )

Configures the DTLS server to automatically drop new connections.

Note: This method is only relevant after calling dtls_server_setup.


Waits for events on the host specified and shuttles packets between the host and its peers. The returned Array will have 4 elements. An EventType, the ENetPacketPeer which generated the event, the event associated data (if any), the event associated channel (if any). If the generated event is EVENT_RECEIVE, the received packet will be queued to the associated ENetPacketPeer.

Call this function regularly to handle connections, disconnections, and to receive new packets.