pies.cf

Packets:

Packet structure:

All packets are sent like this in bytes:
[Packet ID] [Data Type] [Data] [Packet Splitter]
If a packet has multiple data the packet will look something like this”
[Packet ID] [Data Type] [Data] [Data Splitter] [Data Type] [Data] [Packet Splitter]
Data splitter is 0x0 and splits each data

Data Types:

| ID | Name | | — | — | | 0x1 | String | | 0x2 | Number | | 0x3 | Boolean | | 0x99 | Unknown / Error |

Packets:

For now we will not include the level packets since we are just trying to get something working
None means the packet is never sent from the client / server
Empty packets I didn’t bother to document because we’re just getting a basic server then we can add more stuff later

ID	Name	Length of data	Data types	Data to server	Data to client	Additional Infomation
0x1	Auth	1	[string]	[Requested username]	AuthPacketMeta
0x2	Location	3	[string,string,string]	[ignored, x, y]	[username, x, y]	x and y are sent as strings not integers. why? idk
0x3	Sync	2	[string,string]	None	[client username, other players]	other players are a string joined with \|$\|
0x4	Game Update
0x5	Level List
0x6	Level Data
0x7	Level Load
0x9	Chat	1	[string]	[message]	[message]
0x98	Custom	any	any	any	any	packet is never used
0x99	Bad Packet	0	[]	[]	[]	eg. if the client sends a bad packet this can kick them and close the connection. (This packet isn’t required)

Getting the data for a packet

When you recieve you data you will need to split it into packets because they may be stitched together. So you will need to write some code to split them. You will split them at 0xff (255)

Decoding a packet:

Lets say our packet is a int[] bytes

First we will need to get the packet id, easy enough

int packetId = bytes[0]

Then you will need to get all of your packet data by spliting the rest of the data at 0x0

After that you can get the data type:

int dataType = data[0]
switch (dataType) {
  case 0x1:
    // String
    break
  case 0x2:
    // Integer
    // Don't need to handle this right now (also integers are sent werid)
  case 0x3:
    // Boolean
    // Don't need to handle this right now
}

AuthPacketMeta

Note that auth packet uses string so these are sent as strings \

ID	Name
0	REJECT_ALREADY_CONNECTED
1	REJECT_NOT_ALLOWED
2	REJECT_LENGTH
3	REJECT_ALREADY_AUTHED
4	ACCEPT

Example

Lets say we have a server with user1 user2 and a few chat messages. This would be the full packet interaction:
C = CLIENT, S = Server

Direction	Packet	Data	Explanation
C -> S	AUTH	[“user3”]	Client requests “user3” name
S -> C	AUTH	[“4”]	Server accepts username (see AuthPacketMeta)
S -> C	SYNC	[“user3”, “user1|$|user2”]	Server sends all currently connected players
S -> C	LOCATION	[“user”, “100”, “0”]	Server sends user1 location
S -> C	LOCATION	[“user”, “200”, “0”]	Server sends user2 location
S -> C	(Level data)	…	Not gonna explain this rn
C -> S	LOCATION	[””, “0”, “0”]	Client sends server it’s location

Done! Thats the entire packet system.

Actual packets with packet logger

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