Pumpkin

Jamie Little 75994f3302 feat: /place command (#2473 )

* Add /place template command with BlockPlacer trait and tab-completion support

- Add BlockPlacer trait to abstract block placement over ProtoChunk (worldgen)
  and WorldBlockPlacer (live command), used by place_template()
- Implement BlockPlacer for ProtoChunk (pumpkin-world) and WorldBlockPlacer
  (pumpkin crate)
- Add World::queue_block_updates() to insert into unsent_block_changes
  without triggering full set_block_state callbacks
- Generate _generated_all_template_names() at build time from structure
  assets for use in tab-completion suggestions
- Add TemplateNameArgumentType for the new command system with
  list_suggestions() using all_template_names()
- Implement /place template <template> [pos] in the new command system
  (CommandDispatcher, CommandExecutor, ArgumentBuilder)
- Fix borrow-across-await: clone template name to owned String early

* feat: add /place structure and /place jigsaw commands

Adds /place structure <id> [pos] for all structure types with two placement paths:
- Jigsaw structures (ancient_city, bastion_remnant, etc.): fast path using
  JigsawPlacement::add_pieces directly at the target position
- Non-jigsaw structures (desert_pyramid, end_city, etc.): generate pieces
  via dispatch, place into synthetic ProtoChunks with pre-seeded heightmaps
  and a stone floor so pieces can detect terrain, then delta-apply only
  changed blocks to the world via WorldBlockPlacer

Also adds /place jigsaw <pool> <target> <depth> [pos] for manual jigsaw
template placement.

Architecture:
- generate_structure_position() extracts the shared generator dispatch
  from try_generate_structure / lazily_generate_structure (both now
  delegate to it, eliminating ~150 lines of duplicated match arms)
- place_pool_element_templates() extracted from PoolElementStructurePiece
  for reuse by the command with WorldBlockPlacer
- StructureKeys gains from_name()/to_name()/all_names() via codegen
- StructureNameArgumentType and PoolNameArgumentType for tab-completion
- flat_ocean_floor_height_map made pub in ProtoChunk for heightmap seeding

* feat: add /place feature command

Adds /place feature <feature> [pos] for placing configured features
at a specific position. Resolves the PlacedFeature name via from_name(),
resolves the inner ConfiguredFeature from PLACED_FEATURES /
CONFIGURED_FEATURES, then calls ConfiguredFeature::generate() directly
at the target position -- skipping placement modifiers so the feature
appears exactly where specified.

Also adds /place structure improvements:
- Synthetic chunk terrain fill: stone below surface + grass on top, so
  pieces that carve through solid terrain (stronghold corridors, etc.)
  find material to work with. Snapshot/delta ensures only structure
  blocks reach the world.
- Shared snapshot_blocks() and apply_delta() helpers eliminate ~30 lines
  of duplicated diff logic between structure and feature paths.
- ground_y() and chunk_population_seed() helpers replace magic numbers.
- Structure success message now reports the structure name instead of
  the piece count.

Infrastructure:
- PlacedFeature::all_names() generated via pumpkin-codegen for
  tab-completion suggestions in PlacedFeatureNameArgumentType.
- GenerationCache trait implemented for ProtoChunk (single-chunk
  delegation) so ConfiguredFeature::generate() works without the full
  chunk-generation cache system.
- flat_ocean_floor_height_map made pub in ProtoChunk for heightmap
  seeding.
- configured_features and feature modules made pub for access from
  the command crate.

* fix(command): use world settings for place

* docs(place): clarify synthetic terrain delta behavior

2026-07-31 11:45:23 +02:00