2 Commits
Author SHA1 Message Date
AyeZeeBB 46e18900a1 Multiplayer: a sender can no longer flood a player's memory with pose and sound streams
A whole pose from a dedicated server opened a stream under any of its
65,536 numbers, and each stream kept its last 32 poses. Streams were only
dropped once their player had left, so a sender that opened one under
every number for a player who was there (itself) made the receiver keep
millions of poses. Sound streams were open the same way.

- pose_batch::open_stream: a player's new stream ends their old one, and
  no more than 512 streams are held (twice the player limit); both the
  pose and sound receivers open streams only through it.
- A stream is opened only for a player in the session. A refused whole
  pose is not acked, so a real server sends it again; sound is sent whole
  every couple of seconds.
- Tests: the reported flood leaves one stream for one player and 512 for
  65,535; the same for sound, and only admitted players open a stream.
- mesh_tests: HookBatch stubbed, which the session uses since the freeze
  fixes; the test had stopped linking.
2026-10-15 20:02:03 -05:00
AyeZeeBB 38d86e1b72 New pose and sound formats for dedicated servers; direct connections; protocol 44
Poses and skater sound between a dedicated server and its players use new
formats. Lobbies and the links between games are unchanged.

Poses (pose_codec.h, pose_batch.h):
- A pose is rounded once (rotations to 0.08 degrees, positions to a
  millimetre) and sent as its differences from a pose of the same player
  the receiver has acknowledged. Several players' poses share one message.
- The receiver acknowledges messages once a tick; the sender builds only on
  acknowledged poses, or on the whole pose it sent reliably. Loss costs the
  poses in that packet and nothing more.
- Fingers are not sent to players further than "finger_distance" (25 m).
- Games upload their own poses the same way, and the server acknowledges.
- About 300 B a pose at full rate against about 660 B before.
- The server no longer rounds rotations by distance: it saved little.

Sound (sound_codec.h):
- Each sample is sent as what changed since the one before, numbers rounded
  to 1/1024. One reliable message a tick carries every skater a player can
  hear. A stream is sent whole at its start and every two seconds.
- About 106 B a message against 368 B before, on a recording of real play.

Direct connections:
- "connection": "relay" (default) or "direct", with "direct_address" and
  "direct_port". A direct server listens on UDP and is listed with its
  address; players still sign in through Steam.
- Games connect straight to servers that offer it and fall back to the
  relays after 5 s. Setting and "mp direct-connections" to turn it off.

Server:
- "bone_scale_limit" is 1 by default: resized body parts are off unless a
  server allows them.
- Logs Steam's relay network status at start-up and in "net", and watches
  the Steam sign-in.
- "pack_ms" (10): how long Steam may hold a message to pack it with others.
- "steam_debug": logs what Steam's networking says, for connection faults.
- "relay_everything": sends poses and sound through the server even between
  games that have linked, for testing with few players.
- "net" shows pose sizes by rate, the share sent without fingers, and whole
  poses sent.

Game:
- Only ReSkate's nametags are shown; the game's own are removed.
- "mp pose-dump <seconds>" records the local skater's poses and sound.

Tests: pose_codec_tests covers exact round trips, chains of differences,
held fingers, damaged input, the sender and receiver over a link that
delays, loses and reorders, and the sound format; with a recording as its
argument it prints sizes on real play.

Protocol 44: servers and games must both update.
2026-10-07 23:10:13 -05:00