Changelog for GottschCore 1.20.1

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

[2.9.0] - 2026-10-08

Fixed

• SpawnUtil.spawnMob no longer discards every mob it creates. It treated a null return from ForgeEventFactory.onFinalizeSpawn as a cancelled spawn, but Forge returns the spawn data that was passed in (here null) for an ordinary, uncancelled spawn, so every attempt was discarded and proximity spawners in every mod using this class fired and spawned nothing. The return value is now ignored, as Forge's own javadoc says it should be.
• WaterloggedFacingHalfBlock now keeps WATERLOGGED on placement. getStateForPlacement discarded the result of setValue, so a block placed into water pushed the water out instead of waterlogging (since 2.4.0).
• SpawnUtil.spawnMob now rejects a candidate position that fails Mob.checkSpawnObstruction (the full-bounding-box collision test), matching the check vanilla's own BaseSpawner performs. NaturalSpawner.isSpawnPositionOk only tests the target BlockPos (and the block above it) for a full/suffocating block; it says nothing about whether the mob's actual hitbox clips solid geometry once positioned, e.g. a corner, pilaster or partial-shape block adjacent to the target cell. Without this check, spawnMob could hand back a mob already embedded in a wall, which then took suffocation damage and died — intermittently, since it only bit when the random offset happened to land against geometry the single-block check let through.
• SpawnUtil.spawnAndAddMob now adds the created/positioned mob to the world. It previously added an un-positioned, passed-in instance and discarded the actual spawned mob, so mob-set proximity spawners spawned nothing.
• ProximityMobSetSpawnerBlockEntity.execute no longer creates and finalizes a mob twice; it delegates spawning to SpawnUtil.spawnAndAddMob.
• MobSetDataHandler now clears the registry at the start of each reload so removed/edited data packs no longer leave stale entries behind.
• MobSetDataHandler merge/replace now reads the replace flag from the incoming data instead of the existing entry.

Changed

• SpawnUtil reworked so creation and world-insertion are separate steps: spawnMob(...) creates, positions and finalizes a mob but does not add it to the world (an interception point for external mods to modify the entity first); spawnAndAddMob(...) performs the add. Removed the ignored Entity mob parameters from both methods.
• MobSetDataRegistry backing map is now a ConcurrentHashMap (data pack reloads run off-thread); get(null) returns empty.
• MobCount constructor normalizes counts to be non-negative with min <= max.
• WeightedMob reduced to a plain record (removed redundant hand-written accessors and equals/hashCode/toString).

Added

• StrictCodecs (mod.gottsch.forge.gottschcore.json) and its use throughout world.gen.structure.templatesystem: an optional field may now be omitted, but not wrong.
  • DFU's optionalFieldOf(name, default) cannot tell "absent" from "present and malformed" — OptionalFieldCodec maps any decode failure to an empty optional, so the default is substituted either way. Every field in the package was written that way, and the result was silent: a bad probability became 0.0 and the rule went inert; ONE bad entry in a blocks palette emptied the whole palette (a list codec fails as a unit) and the rule then reported itself inactive; a bad floor_growth object became NONE, losing the behaviour entirely. No error, no log line, pack loads, dungeon is merely plainer than authored.
  • All 19 optional fields across AgingProcessor, AgingStage, BlockMatch, DecorationProcessor, DecorationRule and WallGrowthRule now fail the file on a malformed value, with the field name prepended to the message. Omitting a field still yields its default, so packs that simply do not set a key are unaffected.
  • Deliberately narrower than a closed schema: an undeclared key is still ignored, since a shared library's consumers may legitimately carry spare fields. Closing the schema stays a decision for the consuming mod's own records.
• A decoration palette entry may name an ENTITY instead of a block (WeightedGrowth, formerly WeightedBlock). { "entity": "dungeons2:shrieker", "weight": 1 } grows a mob where a mushroom would go. Some things that read as scenery are mobs — GMM's Shrieker and Violet Fungus root themselves and never move — and this lets a datapack treat them as what they look like.
  • An entry names exactly one of block / entity; both or neither is a load error rather than a guess.
  • Spawning happens in finalizeProcessing, which receives a real ServerLevelAccessor, and is clipped to StructurePlaceSettings#getBoundingBox — the chunk box during a piece placement, and the same exactly-once guard vanilla's own StructureTemplate.placeEntities applies. processBlockInfos is NOT chunk-clipped and a piece is placed once per chunk it spans, so without that clip a mob would be spawned once per overlapping chunk. The box is null unless someone set it, which is the honest signal for a single-shot caller; there, everything spawns.
  • Only floor_growth / hanging_growth / floating_growth can place an entity. The oriented rules (cobwebs, corner_cobwebs, wall_growth, underwater_growth) derive a block state from geometry — a facing, a half — which an entity has no equivalent of, so an entity in one of those palettes is refused with a warning rather than guessed at.
• Weighted decoration palettes (WeightedGrowth). DecorationRule and WallGrowthRule blocks lists now accept either a bare block id or {"block": <id>, "weight": <int>}, mixed freely in one list. A bare id means weight 1, so every palette written before this keeps working unchanged and nothing needs migrating; encoding round-trips weight 1 back to a bare id so re-serialising a pack does not rewrite it into the verbose form.
  • An unweighted palette draws exactly as it did before. The pick is one nextInt(totalWeight) walked over the cumulative weights; with all weights 1, totalWeight == size and the walk lands on the index the roll named — the same block, from the same single draw, as the previous blocks.get(nextInt(size)). That is deliberate and pinned by WeightedGrowthTest: these palettes are drawn during worldgen from a position-seeded random, so a draw consuming a different amount of randomness would silently re-decorate every world that already exists.
  • weight is required in the object form, and 0 is legal (an entry parked without deleting it). A palette whose weights are all 0 reports its rule inactive rather than drawing nothing-shaped. Negative weights fail the decode. Required rather than defaulted because DFU's optionalFieldOf(name, default) cannot tell "absent" from "present and invalid" — with a default of 1, "weight": -3 decoded silently as 1.
  • Rules built in code use DecorationRule.of(probability, List<Block>) / WallGrowthRule.of(...), which wrap at weight 1.
• Multi-set support wired end-to-end: StructureMobSetBlockEntity now loads/saves its mobSets list, and ProximityMobSetSpawnerBlockEntity selects a set at trigger time from mobSetNames when no single mobSetName is set.
• Documentation on MobSetDataHandler describing the mob_sets data pack folder and the required AddReloadListenerEvent registration by consuming mods.
• New world.gen.structure.templatesystem package for shared processors built on vanilla's template system (worldgen/processor_list JSON), as opposed to the legacy GottschTemplate path in the parent package.
  • AgingProcessor — ages blocks along multi-stage decay chains and, unlike vanilla's minecraft:rule, carries the source block's state properties onto the replacement. A vanilla ProcessorRule emits a fixed output_state and drops properties, so ageing a stair/slab/wall with it silently resets facing/half/shape; this copies every property the source and replacement share, letting one rule age a whole family of shaped blocks. Chains are graduated: a stage is only reachable if the stage before it was rolled, capped by agings.
  • AgingRule / AgingStage — the datapack model (block / output_blocks / probability).
  • An unknown block id now logs a warning (BlockIds, used by every processor in the package). BuiltInRegistries.BLOCK.byNameCodec() looks strict but never fails: the block registry is a defaulted registry, so an unknown id silently decodes to minecraft:air, and a rule naming mosy_bricks quietly did nothing. It warns rather than failing the load because GottschCore is shared: a pack may legitimately name blocks from a mod the player hasn't installed, and should lose one rule, not stop loading. A consuming mod that wants strictness for its own content should check its shipped files in a test.
  • Randomness is derived from the block's absolute world position (Mth.getSeed(pos), as vanilla's RuleProcessor does) rather than from StructurePlaceSettings, so results are identical regardless of caller — required by callers that run a processor list over procedurally-built blocks, where a piece is processed once per chunk it overlaps and a block on a chunk seam must resolve the same way in both passes.
  • Registration is the consuming mod's job. GottschCore registers no StructureProcessorType (most dependants never touch structure processors), so the class takes a Supplier<StructureProcessorType<?>> and exposes AgingProcessor.codec(supplier) instead of a static CODEC. The registration idiom is documented on the class.
  • Note: alternative chains for the same source block are tried in order and the first that decays wins, so a later chain's authored probability is conditional on the earlier ones missing — two alternatives that should each fire 30% of the time are authored 0.3 and 0.43.
  • DecorationProcessor — decoration that depends on a block's neighbours rather than on the block alone, which neither minecraft:rule nor AgingProcessor can express since both decide one block at a time. Behaviours (all off until a datapack gives them a probability and a palette): cobwebs, corner_cobwebs (an angled web gathered into the junction of a wall with a floor or ceiling, which needs two perpendicular surfaces and orients itself to them, including in rotated and mirrored pieces), wall_growth (clustering multiface growth on full-cube faces), floor_growth / hanging_growth (above and below a dirt match), underwater_growth / floating_growth, and unsupported (deletes blocks left hanging once nothing holds them up). Checks are independent, not a cascade, and only cells the piece itself places as air are ever overwritten. Same codec(supplier) registration idiom as AgingProcessor.
  • BlockMatch / DecorationRule / WallGrowthRule — the datapack model for it.
  • LevelIndependentProcessor — marker for a processor that never touches the level it is handed, deciding purely from the block list, the states in it, and their positions. That property is what lets a caller run a processor over a procedurally-built piece's whole block list instead of only the slice inside the chunk being generated: reading outside the active WorldGenRegion is illegal, so a processor that reads must be clipped and one that doesn't, needn't be. Neighbour-aware processors must be unclipped (a neighbour map built from one chunk's slice is missing everything across the seam); per-block ones benefit, because being unclipped keeps them in the same pass and therefore in authored order. AgingProcessor and DecorationProcessor both implement it. Callers that build blocks procedurally are expected to split their processor list into two passes on this marker; vanilla's own placement path never needs it.
• Test source set (JUnit 5, useJUnitPlatform()), GottschCore's first, with AgingProcessorTest covering property carry-over for stairs/walls/slabs, waterlogging survival, chain-stops-on-miss, the agings cap, alternative-chain precedence, and positional determinism, DecorationProcessorTest covering each decoration behaviour, their independence, seam determinism, and the facing/rotation round trip, WeightedGrowthTest for weighted and entity palettes, StrictFieldsTest for malformed optional fields, and BlockIdsTest for the unknown-block warning.

Deprecated

• world.gen.structure.StructureProcessor (the legacy GottschTemplate placement path). New processors should extend vanilla's net.minecraft...templatesystem.StructureProcessor and register a StructureProcessorType, so they are datapack-authored via worldgen/processor_list and apply to jigsaw/template placement for free.
  • Not scheduled for removal — GottschTemplate is still in use and this is a direction marker for new code, not a removal notice. Consuming mods that extend it will now see deprecation warnings.
  • The legacy type and vanilla's share a simple name but are unrelated and not interchangeable; that is why the new processors live in a templatesystem sub-package, where they cannot shadow vanilla's class on import.

[2.8.0] - 2026-05-25

Added

• New command package with shared formatting tools for admin and debug commands.
  • CommandResponseFormatter — builds coloured status messages (success, failure, warning, info) in shorthand or full form. Works with either plain Component objects or translation keys. Includes formatConfirmPrompt() for two-step destructive command flows.
  • ReportBuilder — fluent builder for structured reports (e.g. inspect commands). Auto-aligns label column, supports sections, blank lines, and notes.
  • FormatterConstants — shared box-drawing characters, semantic icons, style helpers, clickable/suggestable component builders, and buildConfirmButton() for confirmation prompts.
• DimensionCoords — immutable coordinate class that extends Coords with a ResourceKey<Level> dimension field. Supports save()/load() NBT serialization (adds a "dimension" string tag alongside x/y/z). Defaults to the overworld when loading old data without a dimension tag. Factory methods: DimensionCoords.of(dimension, x, y, z), of(dimension, BlockPos), of(dimension, ICoords).

[2.6.0] - 2026-03-26

Changed

• Update BST - dimensional aware.
• ProximitySpawnerBlockEntity.
• Box added new methods.
• SpawnUtil.

Added

• MobCount, MobSetData, MobSetDataHandler, MobSetDataRegistry, WeightedMob
• StructureMobSetBlock, ProximityMobSetSpawnerBlockEntity, StructureMobSetBlockEntity
• MobSetConfiguration

[2.5.1] - 2025-09-23

Changed

• Fixed AbstractProximinityBlockEntity load() method to properly check for "proximity" value.
  • this had prevented proximity from loading properly and always defaulting to the 5D value.

[2.5.0] - 2025-06-15

Added

• Interval implementation for bst package.

[2.4.0] - 2025-05-09

Added

• IHalfBlock block interface
• HalfBlock block
• FacingHalfBlock
• WaterloggedFacingHalfBlock block
• ModUtil class - contains asLocation(), mcLocation() methods, spawnMob(), spawnAndAddMob() methods.

[2.3.0] - 2024-10-27

Changed

• deprecated usage of Coords constructors in favor of static of() methods.

[2.2.0] - 2024-08-20

Changed

• changed WeightedCollection.add() to synchronized.

Added

• WeightedCollection.remove(T key) method.