8.4 KiB
Ordered Descriptive Book grammar (Milestone 5, issue #30)
WritingGrammar interprets the saved OrderedWriting on the server using only SymbolCatalog's schema-v2 semantics. Client display metadata, page names, and supplied translations never determine an Age's meaning. The parser is pure: it returns immutable parsed entries and indexed diagnostics without changing a book or its pages.
New Binder writing has at most one Link Panel plus 27 symbol pages. The Link Panel must be first. A Link-Panel-only book, or an older book with no writing component, keeps the existing random Age path. Any authored supported symbol makes the book a partial or complete grammar. From 0.4.3.0, the server compiles it into a persistent Age plan before consuming Binder inputs or generating chunks.
The supported order follows the representable subset of the Legacy grammar audit: terrain; zero or more biome pages; biome controller; weather; lighting; sky effects; zero or more period or phase modifiers; one celestial page; then zero or more distinct features, each optionally preceded by a compatible block-material page. Biome pages precede the controller that consumes them, and celestial modifiers precede the celestial page. Terrain, controller, weather, lighting, sky, and celestial are single-choice categories; identical repeats are duplicates and differing values conflict. Repeated modifiers are intentional. Biome pages may repeat, preserving author order and any future weighting; feature IDs may not repeat. Angle modifiers remain recognized in the schema but are rejected at binding until a sky renderer can apply sun tilt.
Missing terrain, controller, weather, lighting, celestial, or the controller's minimum biome count is an incomplete warning, not an error: the compiler retains seed-selected traits for missing branches. An omitted terrain page uses a seed-selected profile compatible with authored feature pages, so changing the Age name cannot accidentally select Flat, Void, or Cave terrain for Rocks or Lakes. If no profile can support the writing, binding still rejects it. The minimum biome count is zero for Native, one for Single, and two for Tiled/Grid and Tiny–Huge. Native cannot consume authored biome pages; Single accepts only one. Unknown IDs, schema-v1 display-only symbols, wrong ordering, misplaced modifiers, duplicates, conflicts, missing/extra Link Panels, and oversized writing are errors. The Binder disables output and exposes the first error on the result-slot tooltip. When that error belongs to a page, its thumbnail is tinted and outlined red, the strip scrolls to it, and hovering it shows the diagnostic. This maps the parser's compact entry position back through any empty page positions. Rejected inputs remain removable. Binding an unwritten Descriptive Book rechecks its server-owned writing and reports the first error without creating an Age. A terrain symbol whose profile is unavailable is also rejected before Binder inputs are consumed.
The plan stores the original writing order, the authoritative semantic value of each resolved symbol, the Age seed, and a copy of the selected runtime profile. An explicit terrain page overrides random terrain selection; an omitted terrain uses a seed-selected compatible profile. The built-in Standard, Amplified, Cave, Island, Flat, and Void terrain pages select their matching generation resources. Age loading uses the frozen runtime profile and does not need the original symbol definition or runtime-profile JSON, though its referenced noise, biome-preset, and dimension-type registry entries must remain available. Existing bound books without plans are not reinterpreted. Page-free and Link-Panel-only books keep the pre-existing random path. Biome and environment pages affect new Ages, and the supported feature subset below is compiled into the same frozen plan; instability remains Milestone 6 work.
Supported feature pages (issue #35)
Feature pages come after the celestial section. Their order is retained in the plan and in decoration placement. The Caves page adds a second, Age-seeded vanilla cave-carving pass to Noise terrain, including Standard, Amplified, Island, and Cave terrain. It chooses the vanilla Overworld or Nether cave carver from the source biome. This is separate from the Milestone 7 issue about Cave terrain generation. Flat and Void terrain have no suitable solid noise body and reject Caves with a binder diagnostic.
Flowers, Trees, Huge Trees, Rocks, Surface Lakes, Deep Lakes, and Small Lakes add vanilla placed features after normal biome decoration. Huge Trees currently use vanilla old-growth spruce placement as a modern approximation of Legacy's huge-tree page; it is not the custom Legacy tree generator. Without a preceding material page, Rocks select a valid solid block and each lake page selects a valid source-fluid block from the registered pool. The selection is deterministic for an Age seed and feature ID, so all chunks in that Age use the same material across restarts with the same block registry. The page-specific feature preserves vanilla placement rules other than the biome-list filter, since an authored page deliberately adds it to the Age. Surface and Small Lakes use a more visible one-in-twelve-chunks attempt rate instead of vanilla lava lakes' one-in-two-hundred; Deep Lakes retain their underground placement. Vanilla biome lava lakes are separate and can still appear alongside authored fluid lakes. These decorations require surface Noise terrain; Cave, Flat, and Void reject them. Flowers and both tree pages require at least one surface Overworld biome and only run in compatible chunks; Nether, End, and tagged cave biomes do not receive surface vegetation. Ravines add a separate Age-seeded vanilla canyon-carving pass to Noise terrain. Unsupported feature IDs and missing vanilla registry entries produce diagnostics instead of becoming no-ops.
Material pages are generated for registered full-collision, non-fluid blocks and genuine source-fluid blocks, including eligible blocks supplied by other mods. Blocks with block entities are excluded. Waterlogged plants and coral are not fluid blocks and receive no pages. Valid source-fluid blocks appear only in the Fluid Pages creative tab; valid full-collision solids appear only in Block Pages. Both categories use the same saved material-page semantics. Put a Block Page immediately before Rocks to choose a rock material, or a Fluid Page immediately before Surface Lakes, Deep Lakes, or Small Lakes to choose a lake fluid. A material page left alone, placed before a different category, or attached to an incompatible feature is rejected. Both the feature and material ID are frozen in the saved plan, so future chunks retain their choice after restart. Existing chunks are not retroactively decorated. Portals and the Cave-terrain bug remain separate work.
Crystal Formations are an authored, material-free feature on exposed solid terrain, including Flat terrain; Cave and Void reject the page. Like Legacy, one in fifteen eligible chunks attempts a formation, with the site fixed by the Age seed and chunk coordinates. The modern formation is a compact mound with budding hearts instead of Legacy's long crystal lines. Budding blocks grow through small, medium, and large buds into clusters using vanilla amethyst timing and sounds. Non-silk cluster harvest yields Crystal Shards; four shards craft one Crystal Block. These blocks and shards use 16×16 textures: Legacy's crystal tile for solids and hue-shifted vanilla amethyst sprites for buds and clusters. A page-free Age can also randomly select Crystal Formations; an authored page always retains its exact choice in the saved plan.
The Rivencraft symbol-page creative tabs read a generated index of bundled symbol definitions and group Pages by each definition's category, except biome-controller roles, which appear in a separate Biome Generation tab rather than the Biome tab. Adding another valid JSON symbol under src/main/resources/data/rivencraft/rivencraft/symbols/ includes its page in the matching category tab on the next build; a new bundled category receives its own tab. Registry-derived Block and Fluid Pages have separate tabs and both appear in optional JEI. Link Pages have a separate tab. Blank Pages appear in neither the creative tabs nor JEI's ingredient list. The server catalog still decides whether a page is valid for writing. External server data-pack symbols are not included in this bundled index.