- Use enums for key and mouse actions, rather than integer ids.
- Change TerminalState to always contain a terminal. We now make
TerminalState nullable when we want to skip sending anything.
Here's a fun bug you can try at home:
- Create a new world
- Spawn in a pocket computer, turn it on, and place it in a chest.
- Reload the world - the pocket computer in the chest should now be
off.
- Spawn in a new pocket computer, and turn it on. The computer in chest
will also appear to be on!
This bug has been present since pocket computers were added (27th March,
2024).
When a pocket computer is added to a player's inventory, it is assigned
a unique *per-session* "instance id" , which is used to find the
associated computer. Note the "per-session" there - these ids will be
reused if you reload the world (or restart the server).
In the above bug, we see the following:
- The first pocket computer is assigned an instance id of 0.
- After reloading, the second pocket computer is assigned an instance
id of 0.
- If the first pocket computer was in our inventory, it'd be ticked and
assigned a new instance id. However, because it's in an inventory, it
keeps its old one.
- Both computers look up their client-side computer state and get the
same value, meaning the first pocket computer mirrors the second!
To fix this, we now ensure instance ids are entirely unique (not just
per-session). Rather than sequentially assigning an int, we now use a
random UUID (we probably could get away with a random long, but this
feels more idiomatic).
This has a couple of user-visible changes:
- /computercraft no longer lists instance ids outside of dumping an
individual computer.
- The @c[instance=...] selector uses UUIDs. We still use int instance
ids for the legacy selector, but that'll be removed in a later MC
version.
- Pocket computers now store a UUID rather than an int.
Related to this change (I made this change first, but then they got
kinda mixed up together), we now only create PocketComputerData when
receiving server data. This makes the code a little uglier in some
places (the data may now be null), but means we don't populate the
client-side pocket computer map with computers the server doesn't know
about.
Everything old is new again!
CC's network message implementation has gone through several iterations:
- Originally network messages were implemented with a single class,
which held an packet id/type and and opaque blobs of data (as
string/int/byte/NBT arrays), and a big switch statement to decode and
process this data.
- In 42d3901ee3, we split the messages
into different classes all inheriting from NetworkMessage - this bit
we've stuck with ever since.
Each packet had a `getId(): int` method, which returned the
discriminator for this packet.
- However, getId() was only used when registering the packet, not when
sending, and so in ce0685c31f we
removed it, just passing in a constant integer at registration
instead.
- In 53abe5e56e, we made some relatively
minor changes to make the code more multi-loader/split-source
friendly. However, this meant when we finally came to add Fabric
support (8152f19b6e), we had to
re-implement a lot of Forge's network code.
In 1.20.4, Forge moves to a system much closer to Fabric's (and indeed,
Minecraft's own CustomPacketPayload), and so it makes sense to adapt to
that now. As such, we:
- Add a new MessageType interface. This is implemented by the
loader-specific modules, and holds whatever information is needed to
register the packet (e.g. discriminator, reader function).
- Each NetworkMessage now has a type(): MessageType<?> function. This
is used by the Fabric networking code (and for NeoForge's on 1.20.4)
instead of a class lookup.
- NetworkMessages now creates/stores these MessageType<T>s (much like
we'd do for registries), and provides getters for the
clientbound/serverbound messages. Mod initialisers then call these
getters to register packets.
- For Forge, this is relatively unchanged. For Fabric, we now
`FabricPacket`s.
This adds SPDX license headers to all source code files, following the
REUSE[1] specification. This does not include any asset files (such as
generated JSON files, or textures). While REUSE does support doing so
with ".license" files, for now we define these licences using the
.reuse/dep5 file.
[1]: https://reuse.software/
After several weeks of carefully arranging ribbons, we pull the string
and end up with, ... a bit of a messy bow. There were still some things
I'd missed.
- Split the mod into a common (vanilla-only) project and Forge-specific
project. This gives us room to add Fabric support later on.
- Split the project into main/client source sets. This is not currently
statically checked: we'll do that soon.
- Rename block/item/tile entities to use suffixes rather than prefixes.
Jonathan Coates