the aim of the game here is to avoid allocating lots of tiny arrays, which have a terrible overhead:useful-data ratio.
This reduces the footprint of the mapping from 1.6 MB to 600 KB.
this allows saving about 4 MB of memory, because there are many blocks which have identical states, although they have different IDs.
this relies on a potentially risky assumption that the tags in knownStates won't be modified. If they are modified, the changes will influence all blockstates which share the tag.
However, I don't expect this to happen, and the 4 MB memory saving is substantial enough to be worth the risk.
I don't plan to make wood-like blocks have a dynamic wood/leaves/sapling type, as it's entirely possible their type properties will continue to diverge in future versions.
TreeType includes a bunch of stuff that don't have regular saplings associated with them, such as mangrove and azalea trees.
Mangrove has a dedicated propagule block with different behaviour than the others, and azalea trees are grown from azalea blocks, which are solid and have different behaviour to saplings.
We may also want to account for crimson and warped 'trees' in TreeType too, although I'm not sure if those belong there or not.
TreeType really belongs in the generator package. Not all types of tree may have their own boat type (e.g. azalea).
We can't use WoodType for this either, because some types of wood also don't have associated boat types (crimson, warped).
this was achieved by storing binary representations of the blockstates, rather than the original BlockStateData.
Due to the insane object:data ratio of Tag objects (40:1 for ByteTag for example), modestly sized NBT can explode in memory footprint. This has been previously seen with the absurd 25 MB footprint on file load.
Previously, I attempted to mitigate this by deduplicating tag objects, but this was mitigating a symptom rather than addressing the cause.
We don't actually need to keep the NBT around in memory, since we don't actually use it for anything other than matching blockstates. In this case, we can allow the code to be possibly a little slower, since the lookup is anyway slow and the result will be cached.
In fact, using encoded ordered states as hash keys significantly improves the speed of lookups for stuff like walls, which have many thousands of states.
We keep around generateStateData(), since it's still possible we may need the BlockStateData associated, and it can be easily reconstructed from the binary-encoded representation in BlockStateDictionaryEntry.
since this is contextless (there's no way to know the version of the client requesting the MOTD), we can safely assume that this is not going to vary between protocol versions.
we can use SubChunkExplorerStatus to decide whether or not to update the local light array reference.
We also dereference some properties into local variables, because dereferencing properties is slow. Indirect property dereferences add an extra performance penalty for every layer.
often, protocol updates are done without consideration for the current world format version. We don't want to require the world support to be updated at the same time, since this might delay updates.
this significantly reduces the size of schemas when state remaps are used (see pmmp/BedrockBlockUpgradeSchema@85b83b360e).
in addition, this will likely offer a substantial performance and memory saving when walls get flattened, which will eventually happen.
closes#5724
this uses a (potentially bogus) assumption that the lowest mapped meta value associated with an ID is valid. I don't want to break this during a patch release, and this works for now.
In the future it would probably make more sense to bypass ItemTranslator entirely, and rely solely on the blockstate returned by RuntimeBlockMapping to fetch the correct ID. This is similar to how we serialize items for saving on disk in PM5.
