Port structures, weather, vegetation and safe surface arrivals to 26.3 beta

docs/MINECRAFT_26_3_PORT.md

@@ -681,6 +681,225 @@ resource packaging, and static checks pass for this slice. Generation, visual
 rendering, actual return travel, and restart checks are left to the player;
 no development server is started.
 
+The local `1.0.1.55-beta.1` slice begins the authored structure-set port with
+Villages, Mineshafts, and Strongholds. Saved page occurrences use the existing
+feature plan's new optional structure list. Terrain gates, random-spread
+frequency/spacing scaling, and bounded concentric-ring count/spread follow
+1.21.1. Modern `AbstractSpreadingStructurePlacement` accessors replace the old
+placement-class accessors. Scaled holder copies never mutate global registries.
+
+Structure-state planning includes authored eligibility biomes while continuing
+to sample the actual terrain source. A scoped Structure mixin carries over
+1.21.1's authored biome override. The wrapper handles structure starts itself
+when a structure plan exists, allowing the hook to recognize the authored Age;
+unrelated/unplanned generators remain delegated. Only these three controlled
+families are gated in this slice; remaining structure families, random picks,
+and biome-mismatch instability remain unported. Existing plans without the
+optional list retain their previous structure path. Mod metadata now correctly
+calls this target Beta rather than Alpha.
+
+The player passed Star Fissures. Build/static checks pass for this new slice.
+A disposable dedicated-server startup reached `Done` without mixin-loading
+errors. Its console `/stop` command hit a null-level CommandSourceStack error;
+the exact test JVM was then stopped through SIGTERM and saved/shut down. This
+was a startup check, not authored generation or density validation. The
+disposable world is removed; client authoring, actual structures, density,
+biome overrides, and restart checks are handed to the player.
+
+The local `1.0.1.56-beta.1` follow-up corrects the structure biome override.
+Client logs confirmed the build-55 mixin was applied, but 26.3 JigsawPlacement
+checks `GenerationContext.couldStructureExistInColumn` inside generation,
+before the final check bypassed by the 1.21.1 hook. The replacement ModifyArg
+changes only the biome predicate passed to the GenerationContext constructor
+in Structure.generate for explicitly authored Age structures. Both early
+and final checks now see the override; all other generation constraints and
+unrelated generators retain their existing behavior.
+
+Build/static checks pass. An isolated `--initSettings` bootstrap initialized
+settings without a mixin application error, then FML exited nonzero because
+that settings-only mode creates no server thread. This is not a full server
+or generation pass. No world was created, and the temporary settings directory
+is removed. In-game validation requires a new Age or ungenerated chunks;
+previously rejected chunks are not regenerated. No commit/release is made.
+
+The local `1.0.1.57-beta.1` slice completes the existing 1.21.1 structure-page
+mapping (Dungeons remains its separate placed feature) and enables 26.3's
+Abandoned Camps page. The shared planner now recognizes 15 structure sets.
+Page/terrain restrictions match AgeStructureSelection for the 1.21.1 families;
+Abandoned Camps follows surface noise terrain. No material modifiers are added.
+
+The separate Fortress/Bastion set resources are reused directly from 1.21.1.
+The controlled-set gate includes the vanilla combined Nether set, preventing
+unrequested cross-family placement. All structure pages share the previously
+validated saved list, density logic, and corrected context-level biome override.
+Unknown non-spreading placements are left unchanged rather than cast unsafely.
+Unmodified/no-authored-structure Ages retain their prior native path; previously
+saved authored plans now gate all supported families in new chunks. Instability
+and random feature selection remain pending.
+
+The player passed the build-56 biome fix. Build, diff checks, all 15 registry
+and Creative-page mappings, and target structure resource existence checks pass.
+Packaged Fortress/Bastion definitions match 1.21.1 byte-for-byte. No server is
+started; actual structure placement, terrain-specific limits, repeated density,
+and restart validation are handed to the player. Changes remain local.
+
+The local `1.0.1.58-beta.1` slice ports Caves/Ravines feature pages separately
+from Cave terrain. A new optional saved carver-page list participates in the
+existing feature-plan lifecycle. Grammar accepts noise terrain including Cave,
+rejects Flat/Void and material modifiers, and checks the modern CARVER registry.
+
+26.3 combines carving with terrain construction and exposes carvers that emit
+geometry rather than mutate blocks. A scoped NoiseBasedChunkGenerator mixin
+adds authored geometry to its native CarvingMask immediately before that mask
+is tested/applied. It only acts for the matching runtime Age wrapper, using
+its frozen seed and actual biome resolver. Vanilla applies the combined mask
+with its own aquifer/surface rules; no closed NoiseChunk is accessed afterward.
+The source range, salts, Nether cave selection, and Nether ravine skip match
+1.21.1. Duplicate Caves/Ravines repeat identical seeds in the baseline, so the
+port avoids redundant identical mask passes while retaining authored pages.
+Added terrain volumes still follow the combined terrain operation, as noted
+for the earlier Floating Islands port.
+
+The player passed structure slice 57. Build/static checks and packaging checks
+for the hook, Creative entries, and three required vanilla carvers pass. A
+settings-only bootstrap completed initialization without a mixin application
+error; FML then returned nonzero because no server thread exists in that mode.
+This is not world-generation validation. No world was created; the temporary
+settings directory is removed. Actual carving and restart checks are manual,
+and no commit/push/publication is performed.
+
+The local `1.0.1.59-beta.1` slice replaces stale per-page port information
+and adds the requested red hue for unsupported pages. A shared
+PortAuthoredWriting.isPageImplemented classifier uses the same terrain,
+controller, material/biome, and feature recognizers as the grammar, without
+misclassifying context-dependent modifiers/controllers by testing them alone.
+Page tooltips, the extracted item-render color, and the Binder background use
+this single availability check. Tinting does not generate extra textures or
+change stored page data. Corrupted-page names/descriptions remain obfuscated.
+
+Port language overrides remove the old Standard/one-Biome claim, distinguish
+implemented/unimplemented pages and invalid combinations, and correct all
+15 structure-family descriptions, material adjacency, and selected terrain/
+feature restrictions. The 1.21.1 language assets are unchanged. This is a UI
+and information slice, not new generation functionality.
+
+The player passed Caves/Ravines. Build, diff checks, unique language-key checks,
+and packaged-language override checks pass. No server/world is started.
+Inventory tint, Binder tint/layering, and tooltip readability await the
+player's visual check. Changes remain local and unpublished.
+
+The local `1.0.1.60-beta.1` slice implements the four requested 26.3-only
+vegetation pages: Poplar Trees, Fallen Poplar Trees, Red Shrubs, and Shelf
+Mushrooms. They extend PortVegetationPlan recognition, so grammar, saved plans,
+Creative status, item tint, and tooltip availability agree without another
+page list. The existing ordered vegetation cap and surface-terrain/biome
+restrictions are retained. The 1.21.1 code/assets are unchanged.
+
+Poplar Trees selects only the three vanilla poplar variants, retaining their
+relative native weights and six placement attempts. Fallen poplars reuse the
+vanilla feature but add authored in-square/surface placement before its sapling
+check; the vanilla placed feature alone has no surface-height placement. Red
+Shrubs directly reuses its registered patch. No tree/shrub algorithm or artwork
+is duplicated.
+
+Shelf Mushrooms is a tree decorator in 26.3, not a placed feature. The authored
+page therefore applies ShelfMushroomDecorator to existing connected log hosts
+at its position in the vegetation sequence. Section palettes skip log-free
+sections, repeated pages reuse the host scan, and tree placements invalidate
+that cache. Host ordering and page seeds are deterministic; callback writes
+are chunk-local, fluid-free, supported, and height-bounded. The decorator keeps
+its native standing/fallen logic and side/age/adjacency checks. This is an
+authored extension using the native decorator, not a new vanilla feature ID.
+
+Build/static and resource-reference checks pass. The four pages' descriptions
+explain their actual effects and requirements. No server/world is started;
+the player validates vegetation appearance, support/tint, ordering, and restart.
+Changes remain local and unpublished.
+
+The local `1.0.1.61-beta.1` follow-up separates log-hosted Shelf Mushrooms
+from surface plants. A shared requiresSurface classification now governs
+terrain/explicit-biome validation; decoration handles Shelf Mushrooms before
+the surface-biome skip. Trees, shrubs, and flowers retain their restrictions.
+Void/Cave/End-biome log hosts are no longer excluded by the vegetation path.
+
+The host scan is a stable log-position list rather than connected tree groups.
+Native tree decorators assume a meaningful base and only decorate a limited
+height band, which is unsuitable for log tendrils. The authored extension
+therefore checks exposed log faces at all heights, reusing the native decorator's
+replaceability/water predicate and block facing/age/survival rules, with spacing
+and chunk bounds. Cached scans still avoid repeated full-volume work. No tree
+page or log-producing page is required, but actual log hosts must exist during
+chunk generation. This supersedes slice 60's whole-tree height-band behavior.
+
+Build/static checks pass. Manual validation: new Void + Oak Log + Tendrils +
+Shelf Mushrooms Age, without any tree page; inspect exposed log faces and
+restart/new-chunk generation. No server is started and nothing is published.
+
+The player passed the local `1.0.1.62-beta.1` sound slice: the complete 1.21.1
+sound manifest/OGGs are reused, book travel emits modifier-selected audio and
+cloud bursts, and Star Fissures play audio after arrival as well as departure.
+Portal/meteor events are registered but their gameplay ports remain separate.
+
+The local `1.0.1.63-beta.1` slice adds authored Normal/Fast/Slow/Off/Always/Storm
+weather policies. One policy is accepted per book, with availability/tint and
+tooltips following the shared classifier. Cave terrain always suppresses it.
+An omitted policy defaults to Normal for now; random-trait selection is pending.
+
+Unlike 1.21.1, 26.3 ServerLevel.getWeatherData delegates to the server's shared
+weather object. A scoped Runtime Age ServerLevel subclass instead loads native
+WeatherData from that Age's data storage, alongside its saved policy. Native
+weather ticking and client packets remain in charge; only the data owner and
+Legacy-style duration policy change. The constructor replaces inherited global
+rain/thunder visual levels before publishing the level. Retirement, reseeding,
+reload and restart retain the policy through existing per-Age storage lifecycle.
+Vanilla /weather remains a global server command; the Age policy is not a
+global command override. Native biome precipitation rules still apply.
+
+Build/diff checks pass. A disposable dedicated server created all six weather
+policies: every Age reported independent native data and the expected flags/
+duration ranges. Setting global thunder left the Off Age clear. Unload/reload
+retained Storm, and a full stop/restart restored all six policies and their
+live timers. Both servers shut down cleanly; the temporary test world is
+deleted after completion. Client appearance, cross-Age travel, authoring/tint,
+and Cave suppression remain manual checks.
+No commit/push/publication is authorized by the player's testing pass alone.
+
+The local `1.0.1.64-beta.1` follow-up fixes weather-only authoring. Build 63's
+server weather checks bypassed the Binder's biome compiler, whose exclusion
+list did not yet include weather. As a result weather/storm was incorrectly
+resolved as a biome ID despite grammar acceptance. The biome compiler now
+selects actual biome-category entries after full-book grammar validation;
+controllers retain their separate handling. This avoids repeating the same
+missed-exclusion bug as more non-biome page families are ported. The operator
+weather fixture now calls that compiler before backend creation. All six
+weather-only symbol lists compiled and created their expected weather states
+on a fresh dedicated server. Build/diff checks pass. The server shut down
+cleanly and its disposable world was removed; player GUI validation remains.
+
+The local `1.0.1.65-beta.1` spawn correction traces non-Cave arrival columns
+from maximum build height, inspecting actual fully generated chunk blocks.
+The configured Flat-layer shortcut could select ground below later authored
+terrain, and the old heightmap-only path did not explicitly ensure an exposed
+surface. The new path stops at the first fluid/leaves/collision, requires dry
+footing and headroom, and otherwise tries the next column rather than searching
+below an obstruction. Chunk lookup is cached per column and a mutable position
+avoids per-air-block allocations. A fallback platform goes above the actual
+highest obstruction; empty Void retains floor Y=63. Surface footing accepts
+leaves, rejects fluid-bearing floors, and checks build/border bounds.
+
+Stored non-Cave Star Fissure arrivals also use the surface search rather than
+accepting old underground pockets. Cave terrain keeps its Y=64-down search.
+Exact bound Linking Books and the general fissure Overworld-return anchor
+search are not redirected to the sky. A read-only surface probe command helps
+validate the chosen column/nearby surface (chunk generation is possible).
+Build/diff checks pass. A disposable dedicated-server probe selected Y=4 on
+plain Flat ground, Y=141 above leaves placed at Y=140, and a neighboring dry
+column instead of descending below water added above those leaves. A larger
+roof-fixture fill was rejected by vanilla because some target chunks were not
+loaded; that fixture is not claimed as tested. The server shut down cleanly,
+and its temporary world was deleted. Actual player arrival in the affected
+Age and the unchanged Cave/Linking Book paths remain manual checks.
+
 ## Verification of this first slice
 
 The 1.21.1 `compileJava` and `build` tasks passed offline after the backend