15 KiB
Age runtime profiles
Rivencraft loads Age runtime profiles from server data packs at
data/<namespace>/rivencraft/age_profiles/<name>.json. The resulting profile ID
is <namespace>:<name>. Profiles select registered world-generation resources;
they do not contain an Age's seed, name, spawn, or rolled traits.
Schema version 1
{
"schema_version": 1,
"terrain": "noise",
"noise_settings": "minecraft:overworld",
"biome_preset": "minecraft:overworld",
"dimension_type": "minecraft:overworld"
}
terrain is noise, flat, or void. Noise profiles require
noise_settings and biome_preset references. Every profile requires a
dimension_type reference. Omitted resource references use the Overworld
entry. Rivencraft validates all referenced entries against the loaded dynamic
registries during data-pack reload. An invalid profile is rejected.
The built-in profile IDs are rivencraft:standard, amplified, island,
cave, flat, and void. Their JSON files are ordinary built-in data-pack
resources and can be overridden by a higher-priority pack. The example under
docs/example-age-profile-pack can be copied into a world's datapacks
directory. Valid custom profiles join the stable, sorted pool used when a new
Age rolls its base terrain; the selected ID is then persisted with that Age.
Each built-in profile now has a matching terrain/<name> Symbol Page. Put one
of those pages after the Link Panel in a Book Binder to select that terrain
instead of the seed-selected random profile. Standard, Amplified, and Cave use
their corresponding registered noise settings; Island uses Minecraft's
floating-islands noise settings; Flat and Void use flat-source generators.
The Cave and Island pages are Rivencraft terrain choices based on existing
profiles, not claims that Legacy had identically named terrain symbols.
Every family retains a safe cobblestone arrival platform. An omitted terrain
page still uses the deterministic seed-selected profile.
The separate Floating Islands feature page adds rare high-altitude island clusters above Standard, Amplified, Sky Islands, Flat, or Void terrain; it does not replace the terrain page. The feature is seeded by the Age and saved with the written plan, so revisiting an Age recreates the same islands. Without a preceding Block page, the Age seed chooses one valid full-collision block from the Block Pages pool for the island body. A full-block material page immediately before Floating Islands overrides that choice. Ordinary surface biomes still get dirt/grass top layers; Nether and End biomes use the chosen block throughout. The feature is additive even on Sky Islands terrain, which already forms its own islands. Cave terrain rejects it. A page-free random Age may also roll Floating Islands as one of its material features.
An unpaired Block or Fluid page chooses a compatible feature from the Age seed: full blocks can become Rocks, Floating Islands, Tendrils, Spheres, or Spikes; source fluids can become one of the lake features. Flat terrain can use Floating Islands, Tendrils, Spheres, or Spikes; Void can use Floating Islands, Tendrils, or Spheres; Cave can use Spheres or Tendrils. A page-free random Age rolls zero, one, or two distinct compatible material features, choosing each material from the Block or Fluid Pages pool. The choices are saved on the Age definition, so opening the Age again does not reroll them. Repeated Block/Fluid and Feature pages remain separate entries in authored writing. Each unpaired material gets its own compatible feature, and repeated decorations use separate placement rolls. Repeated unmodified feature pages choose different compatible materials until their material pool is exhausted.
Structure pages are separate Feature symbols. Legacy's Dungeons, Mineshafts, Nether Fortresses, Strongholds, and Villages have writable pages, as do modern Trial Chambers, Bastion Remnants, Buried Treasure, Shipwrecks, Ocean Ruins, Pillager Outposts, Ruined Portals, Nether Fossils, Ancient Cities, and Trail Ruins. They use Minecraft's 1.21.1 structure templates and placement rules, not a recreation of 1.12.2 structure geometry. A page enables only its own structure set; absent pages do not inherit these structures from a biome. Nether Fortresses and Bastions use separate sets instead of vanilla's shared Nether-complexes set, so writing one does not enable the other. Dungeons use the vanilla monster-room feature with eight attempts per chunk; unpaged Ages do not inherit biome-default monster-room attempts. A page-free random Age may choose zero to two distinct compatible structure types, frozen on creation. An authored structure needs a compatible biome in the Age's selected pool. Fortresses, Bastions, and Nether Fossils require Cave terrain plus a Nether biome; surface-only structures reject Cave terrain. Void rejects all of these structure pages. Villages and Strongholds can also be written into Flat Ages.
For visual testing, write a Standard/Plains/Single Age with Mineshafts,
Villages, and Trial Chambers, then use /locate structure in that Age to find
each. An unwritten Pillager Outpost should not locate there. Test a Cave Age
with Nether Wastes/Single and either the Nether Fortresses or Bastion page:
only the selected type should locate. Ocean structures need their matching
ocean or beach biome page; Ancient Cities need Deep Dark. Check the new pages
in Rivencraft's Feature creative tab and JEI as well.
For an in-game visual check, bind Descriptive Books with a Link Panel, one of Standard, Amplified, Sky Islands, Flat, or Void terrain, and the Floating Islands feature page in that order. Fly through each Age at roughly Y=170–220 and verify the elevated clusters appear above its unchanged base terrain. Reopen the same Age to check that island positions stay fixed. Islands should be less common than in the first test build (one source chunk in 128 instead of 64). Sky Islands should retain its terrain islands and gain occasional additional feature islands. Try Cave terrain too; the Binder should reject that pairing.
Skylands is a separate subtractive feature, not the Sky Islands terrain profile or the additive Floating Islands feature. Following Legacy's primer filter, it removes base terrain below a smooth, seven-octave cutoff around world Y=76 and removes liquid above the cutoff. The selected terrain still generates first; Floating Islands and Tendrils are added afterward, so they can coexist with Skylands. Skylands has no Block-page modifier. It can be authored on every terrain, though Flat loses its low ground and Void has no base terrain to change. Page-free random noise Ages have a seeded one-in-eight chance to gain Skylands; random Flat and Void Ages do not roll this ineffective filter. The cloud-height and horizon changes from Legacy are not included yet.
For an in-game check, compare Standard terrain with and without a Skylands page. Skylands should leave upper hills suspended over open space, while a Floating Islands page instead adds isolated high islands without removing the ground below. Try Sky Islands terrain plus Skylands to confirm the page filters the terrain rather than replacing its generator. A book with both Skylands and Floating Islands should retain the added feature islands above the cutoff.
The Tendrils feature adapts Legacy's winding, branching cave-node geometry into solid tubes. It is additive on all current terrain families, including Flat, Void, and Cave; it does not change biome selection. A preceding full- collision Block page chooses the tendril material. Otherwise the Age seed chooses a valid Block Pages material, consistent with other authored material features. Page-free random Ages can select Tendrils as a solid-material feature, including on Cave terrain where the surface material features are unavailable. The shape and placement use only the Age seed and source-chunk coordinates, so revisiting an Age recreates the same geometry.
Spheres and Spikes are two separate Feature pages. Spheres adds winding chains of solid sphere nodes within terrain generation; like Tendrils, it works on all terrain families, even Void and Cave. Spikes is a later, rarer surface decoration (roughly one attempt per 18 chunks) that rises from solid ground on Standard, Amplified, Sky Islands, or Flat terrain. Cave and Void reject the Spikes page because they do not provide a suitable exposed surface. Each page accepts its own immediately preceding full-collision Block page; without one, the Age seed chooses a compatible material. The pages remain distinct in the catalog, Creative menu, JEI, ordered writing, and saved Age definition. Page-free random Ages can select either where compatible.
For an in-game check, make separate Void/Spheres and Flat/Spikes books with Glowstone Block pages directly before their respective Feature pages. Spheres should form connected bright globes across chunk boundaries in Void; Spikes should appear as rare upward clusters rooted on the Flat surface. Revisit the same Ages to confirm stable locations. Check that a Void/Spikes book is rejected, and that Spheres and Spikes remain two independently selectable pages in Creative and JEI.
For a clear visual check, bind a Void Age with a Glowstone Block page followed by Tendrils. Fly around world Y=0–120 across several chunks: branching solid forms should appear in the otherwise empty dimension, continue across chunk borders, and remain in place after leaving and returning. Repeat with a lone Tendrils page to confirm its seed-chosen material, and with Cave terrain to confirm the feature does not require a surface biome.
Written biome selection (generation version 16)
Biome pages follow the terrain page and precede the distribution-control page
in the Binder. Bundled controls are Native, Single, Tiled, Grid, and Tiny through
Huge regions. Single needs one distinct biome; Tiled/Grid and Tiny–Huge need
two. An authored book receives seeded filler only when it falls below that
minimum, while extra authored pages are retained as weighted entries. A book
with no biome pages selects a seeded count from two up to the number of
eligible biomes for Tiled/Grid and Tiny–Huge. The eligible pool comes from the
terrain's biome preset, or #rivencraft:cave_biomes for Cave terrain, so future
biome integrations can expand it without changing the count rule. Single uses
one; Native uses its preset biome pool. This random-age maximum does not truncate
authored pages: the Binder's 27 symbol-page positions bound an authored book.
Native cannot be paired with explicit biome pages. Legacy filled Tiny–Huge to
three; Rivencraft deliberately uses two so a pair of written biome pages stays
exactly as written.
The Biome Pages creative tab offers pages for every registered vanilla biome.
Hand-authored symbol definitions take precedence; the remaining vanilla pages
are generated from the biome registry, so they do not each need a JSON file.
Custom/modded biomes still require a data-pack symbol definition.
Standard, Amplified, and Sky Island terrain fill from the vanilla Overworld
biome preset, including its underground Lush Caves, Dripstone Caves, and Deep
Dark biomes. Standard terrain therefore keeps Overworld-style cave generation,
and cave biome pages can also be written explicitly. Sky islands can use an
explicitly authored End biome page.
Cave terrain fills only from #rivencraft:cave_biomes (Lush Caves, Dripstone
Caves, and Deep Dark by default); explicitly authored Nether biome pages are
also accepted. Other cave/biome pairings are diagnosed and blocked for now.
Milestone 6 instability should allow such illegal combinations as unstable
Ages, without silently treating them as ordinary cave generation. Flat terrain
uses Overworld choices when a distribution is authored; its Native default
remains Plains. Void terrain defaults to The Void when no biome page is written,
but accepts authored biome pages. One authored biome uses Single distribution
when no controller is written. An explicit multi-biome distribution needs enough
authored biomes; The Void is not silently added to fill missing positions. These
biome regions exist even without blocks or a Floating Islands page, so biome-
dependent weather and optional season behavior can still vary there. To check
this in-game, bind Void terrain with a Desert Biome page and no feature page:
the Age should be empty while F3 reports Desert. A Void book without biome
pages should instead report The Void.
The resolved list of biome IDs, their order/repetitions, and distribution are frozen into the Age plan. A removed biome ID emits a warning and uses an eligible fallback for that load; restoring the biome recovers the original selection. Generation-version-15 Ages keep their prior registry-wide biome selection algorithm instead of being silently regenerated.
Written environment
Lighting pages select Normal, Dark, or Bright lighting for the new Age. A Sky page selects Minecraft's Overworld, Nether, or End sky effects; the chosen effects also determine the destination preview backdrop. Overworld sky tint continues to come from the destination biome. A written sky changes only that Age's dimension type, not the source world or other Ages.
Normal, Fast, Slow, Off, Always, and Storm weather pages use the existing Age weather controller. Zero, Half, Full, and Double Length pages set the day-cycle period, and Nadir, Rising, Zenith, and Setting pages set its initial phase. Repeated numeric modifiers combine in written order. A Zero Length Age keeps the nonzero minimum clock rate that avoids client skybox bounce. Pages for Cloudy, forced Rain, and Snow are not offered: vanilla precipitation rendering cannot reproduce those Legacy distinctions yet, and Snow remains planned for the optional season integrations. A data pack that supplies these unsupported weather choices receives a binding error rather than a false success.
The category creative tabs and optional JEI page ingredients use the same generated index of bundled environment symbols. Existing Age definitions and page-free random Ages retain their saved or seeded environment unchanged.
Persistence and reload behavior
An Age permanently stores its selected profile ID, generation version, seed,
and rolled traits. For an authored Age, the generation plan also stores a
copy of the resolved runtime profile: terrain shape, noise settings, biome
preset, and dimension type. /reload cannot reinterpret that plan; an unloaded
authored Age uses the saved profile snapshot when it loads, even if the defining
symbol or profile JSON has since changed. An older, page-free Age has no plan
and continues to resolve its saved profile ID at load time.
Registered noise, biome-preset, and dimension-type IDs are validated when profiles load. Before loading an authored Age, the saved references are checked again. If a data pack supplying one has been removed, the dimension stays unloaded and the log identifies the missing resource; the Age's plan is not silently replaced. Restore the pack to load that Age. A custom dimension type retains its own skylight capability: normal lighting cannot make a Nether-style type skylit.
A profile removed after a page-free Age was created resolves to rivencraft:standard.
The legacy rivencraft:random_vanilla alias also resolves to standard.
Rivencraft logs this fallback. Invalid built-in overrides do not replace the
required built-in definitions; a reload fails if a required built-in profile
is absent after resource resolution.
Only schema version 1 is accepted. A future schema change must add an explicit migration path before incrementing the version. The saved Age generation version remains independent of this data-pack schema and is never silently rewritten.