Conitec 3d gamestudio-source development 用户手册

The protocol is optimized for using as less bandwidth as possible. Only parameters that have
changed are sent over the network. Sending a player's changed XYZ coordinate from the server
to the client, for instance, needs only 12 bytes (including header). A dead reckoning mechanism
is used for extrapolating positions and angles between cycles.

The structure of the messages is a single-byte code, followed by code-dependant informations.
When describing the content of messages, we use the following conventions: 

an unsigned integer, on one byte.

a signed integer, on two bytes, Big Endian order (Intel order).

a signed integer, on four bytes, Big Endian order (Intel order).

a floating point number, on four bytes, Big Endian order (Intel order).

a fixed point number in 22.10 format, on four bytes, Big Endian order (Intel order).

a sequence of characters, terminated by 0 ('\0')

a short, to be multiplied by 360.0/65535.0 to convert it to degrees.

a coordinate packed in three bytes by dividing it by 8

either 

 or 

 depending on the 

 variable

a value packed into one byte to be multiplied by x/255.0.

The following commands are used for transferring information from a client to the server. 

Filler

byte

for

inflating

UDP

messages to a minimum length.

Request for joining the session
(TCP).

Request creating an entity with
given model name, and link the
client to it (TCP).

Request removing entity on the
server (TCP). 

Sent after each client frame (UDP). If
a client does not send anything for
more

than

5

seconds,

it

is

automatically disconnected by the
server.

Inform server that client has loaded
a level (TCP).

Send a variable or an array (TCP).

Send a string (TCP).