Finish alpha.30.7 with natural island treasures, direct rails and dry ruins

README.md

@@ -21,6 +21,17 @@ le relief et les souterrains de la 24, retire la montgolfière et travaille les
 marais souterrains et la restauration de vrais modèles d’épaves vanilla. Voir le
 [chantier et ses limites](docs/generation-alpha27.md).
 
+## Alpha.30.7 — trésors aériens et vestiges asséchés
+
+Le relief de 30.6 est conservé. Les nouveaux morceaux de terrain aérien reçoivent
+les minerais et trésors des anciens îlots artificiels, retirés de la planification.
+Les rails privilégient les lignes directes. Une seconde traversée souterraine et
+quelques petites ruines océaniques asséchées sont cherchées lorsque le terrain
+les accueille.
+
+Voir [la génération](docs/generation-alpha30.7.md) et [les essais](docs/testing-alpha30.7.md).
+**Nouveau monde requis.**
+
 ## Alpha.30.6 — village souterrain et voies ramifiées
 
 La déformation du terrain 30.5 est légèrement renforcée. Un village vanilla

docs/generation-alpha30.7.md

@@ -0,0 +1,66 @@
+# Alpha.30.7 — dernières installations de la génération
+
+Cette passe conserve le relief et les morceaux de terrain naturel de l’alpha.30.6.
+Les fonctions de densité, cavités, rivières, biomes et tailles ne changent pas.
+Minecraft reste en 26.3-pre-2 ; plafond à Y640, Moyen 724 par défaut.
+Créer un nouveau monde pour voir la nouvelle répartition des installations.
+
+## Trésors dans le terrain aérien
+
+Les deux anciens îlots minéraux construits comme des structures ne sont plus
+planifiés dans les nouveaux mondes. Les deux morceaux naturels de Petit et Moyen,
+ou les trois de Grand, portent désormais chacun un coffre enterré et des filons.
+Le coffre utilise la table de richesses aériennes existante, uniquement vanilla.
+Aucun objet de quête n’est ajouté.
+
+L’enrichissement remplace seulement la roche existante entre Y300 et Y399 :
+charbon, cuivre et fer dans les couches supérieures ; or, lapis, redstone, diamant
+et émeraude plus à l’intérieur. La profondeur est mesurée dans chaque colonne de
+l’îlot. Les réserves sont finies, sans renouvellement après minage ou pillage.
+Le profil est volontairement très riche ; les comptages par minerai figurent
+dans les rapports aériens de l’atlas. La forme, le sol et la végétation de ces morceaux naturels restent ceux de 30.6.
+L’ancienne cascade artificielle disparaît avec son ancien îlot.
+
+Les deux navires restaurés restent près de leurs côtes. Les nouveaux trésors
+possèdent des départs natifs, des pièces sauvegardées et des réservations limitées
+à leurs emprises. Ils utilisent l’identifiant de localisation
+`sanctuary:aerial_mineral_islet`. Le terrain aérien naturel existe également quand
+les structures sont désactivées ; ses coffres et son enrichissement expérimental
+suivent les options de structures.
+
+## Rails et traversées
+
+Chaque prolongement ferroviaire garde son axe. Un terrain incompatible termine
+le parcours au lieu de provoquer une succession de virages. Les embranchements
+partent des longues lignes principales ; les extensions successives ne produisent
+plus de branches tournantes récursives. Une séparation évite les lignes presque
+parallèles autour d’une même voie. Cela peut réduire la longueur totale du réseau :
+les 6–8 % anciennement évoqués ne constituent pas un quota.
+
+Après la première traversée souterraine, une seconde recherche est effectuée dans
+l’espace restant. Elle respecte les mêmes règles de sol, couverture et accès,
+avec une séparation de 24 blocs autour des modules de la première. Si elle ne
+tient pas dans le terrain et le budget de recherche, la première reste conservée.
+Chaque traversée possède ses deux accès ; aucun croisement aveugle n’est creusé
+pour forcer la seconde.
+
+## Ruines d’un ancien fond marin
+
+`sanctuary:drained_ocean_ruin` place quelques petits templates vanilla de ruines
+océaniques chaudes dans les cavités sèches existantes entre Y60 et Y174. Trois
+emplacements sont recherchés, quatre en Grand, sans garantie de quantité. Les
+refus de sol, dégagement ou réservation sont journalisés. Aucun nouveau grand
+volume souterrain n’est creusé pour les accueillir.
+
+Les modèles vanilla habités (`warm_2`, `warm_3`, `warm_4`, `warm_5`, `warm_8`),
+leur dégradation et leurs tables de butin sont conservés.
+Les marqueurs d’habitants placent des zombies vanilla persistants ; des coraux
+morts complètent les vestiges et sont posés avec `waterlogged=false`. Les blocs
+gorgés d’eau sont asséchés. La protection contre la décoration ultérieure reste
+limitée à la petite emprise de chaque ruine. Les pièces
+sauvegardées conservent leur altitude souterraine au lieu de recalculer un fond
+océanique lors du rechargement. Ces ruines Sanctuary ont leur propre identifiant ;
+elles ne remplacent pas les ruines aquatiques des expansions océaniques.
+
+Voir [les vérifications](testing-alpha30.7.md). La structure envisagée à Y600 reste
+une idée ; cette livraison n’ajoute rien à cette hauteur.

docs/terrain-atlas.md

@@ -100,3 +100,29 @@ build/atlas-venv/bin/python scripts/structure_atlas.py \
   mods/sanctuary/build/run/gameTest/diagnostics/atlas306/terrain-724-0.json \
   --output build/atlas306/structures
 ```
+
+## Finition 30.7
+
+Le terrain de 30.6 est conservé. L’export natif est répété sur les neuf couples
+512 / 724 / 1 024 × 0 / 42 / -7228211907433324401 pour comparer exactement les
+colonnes et les coupes avant décoration. L’enrichissement des minerais et les
+petites structures n’appartiennent pas à ce champ de densité.
+
+`scripts/finishing_atlas.py` superpose les rails planifiés, les axes des traversées
+parcourues dans les blocs, les ruines asséchées et les réservations aériennes.
+Les rectangles représentent les emprises ; ils ne représentent pas des îlots
+rectangulaires. Le script refuse des rapports de graines ou tailles différentes
+et des témoins natifs non réussis.
+
+```sh
+build/atlas-venv/bin/python scripts/finishing_atlas.py \
+  --terrain build/atlas307/raw/terrain-724-0.json \
+  --village CHEMIN_DU_RAPPORT_VILLAGE \
+  --transit CHEMIN_DU_RAPPORT_TRANSIT \
+  --aerial CHEMIN_DU_RAPPORT_AERIEN \
+  --ruins CHEMIN_DU_RAPPORT_RUINES --output build/atlas307/installations
+```
+
+Les preuves, cartes PNG/PDF et leurs empreintes sont ajoutées à l’archive de
+livraison. Ces cartes sont des vues de diagnostic opérateur, pas des cartes
+automatiquement révélées aux joueurs.

docs/testing-alpha30.7.md

@@ -0,0 +1,91 @@
+# Vérifications alpha.30.7
+
+Essais automatisés sur macOS, Java 25, Minecraft 26.3-pre-2. Aucun essai Windows
+ni visite visuelle interactive de l’alpha.30.7 n’a été réalisé. Les mondes des
+fixtures restent dans le dossier de développement ignoré.
+
+## Témoins dans de vrais chunks
+
+| Témoin | Terrain aérien enrichi | Navires / villageois | Traversées praticables | Village abandonné | Mines |
+|---|---:|---:|---|---|---:|
+| Moyen 724, graine 0 | 2 corps, 2 coffres | 2 / 2 | 2, portées 272 et 204 blocs | 15 maisons, 99 pièces, 10 zombie-villageois | 1 |
+| Grand 1 024, graine -7228211907433324401 | 3 corps, 3 coffres | 2 / 2 | 1, portée 374 blocs | 12 maisons, 70 pièces, 9 zombie-villageois | 2 |
+
+La seconde traversée du Grand est refusée : aucun accès ne satisfait le contrôle
+civil. La première reste générée et parcourable. « Deux si la place le permet »
+ne signifie donc pas deux dans chaque monde.
+
+Les fixtures aériennes contrôlent les départs natifs, les coffres enterrés,
+les huit minerais dans chaque corps, la présence des deux villageois, puis
+pillent les coffres, minent un témoin et déplacent les habitants dans leur monde
+jetable. Les fixtures de traversée vérifient les blocs de circulation de chaque
+réseau séparément, ses accès et ses parois. Le village conserve ses pièces
+Jigsaw, ses coffres et ses habitants. Les rails sont mesurés comme plans et
+ballast : aucune circulation de wagonnet n’est certifiée sur les voies abandonnées.
+
+## Ruines asséchées
+
+Sur Moyen / 0 : trois ruines réellement posées, trois coffres, trois zombies
+persistants et neuf coraux morts. Le contrôle après ticks vérifie l’absence
+d’eau dans les emprises, les blocs vanilla et le roundtrip NBT des départs.
+
+Sur Grand / -7228211907433324401 : quatre ruines réellement posées, quatre
+coffres, cinq zombies persistants et douze coraux morts. La passe dédiée réussit
+en 3 min 21 s, dont 15 s d’exécution des deux tests après préparation du monde.
+
+Le test a révélé que les coraux morts ont un état `waterlogged=true` par défaut.
+Ils sont désormais explicitement posés secs. La correction est locale à la ruine ;
+aucun filtre étendu ne supprime les eaux ou la décoration des grottes voisines.
+
+Les sauvegardes de pièces et les marqueurs d’habitants sont contrôlés par
+sérialisation native. Une reprise complète dans un nouveau processus JVM après
+pillage et démolition n’a pas été rejouée pour cette livraison ; elle ne doit pas
+être confondue avec ce roundtrip NBT.
+
+## Commandes et portée
+
+Une première exécution complète de `check build` a réussi avec 26 GameTests.
+Après la correction finale des coraux, les contrôles purs et les cinq GameTests
+ciblant les comportements modifiés ont tous réussi (5 min 47 s) :
+
+```sh
+./gradlew check build \
+  -PsanctuaryFocusedTests=aerial,transit,village,drained \
+  -PsanctuaryAerial24Tests=true -PsanctuaryTransit29Tests=true
+```
+
+Le sélecteur `sanctuaryFocusedTests` limite seulement les fixtures natives ;
+les contrôles de `check` restent exécutés. Sans ce paramètre, la suite native
+complète conserve son fonctionnement habituel.
+
+Les témoins Grand pour les îlots, navires, traversée et village proviennent de
+la passe précédente de cette même livraison. Seuls la pose sèche des coraux et
+les contrôles locaux des ruines ont ensuite changé ; la validation dédiée des
+ruines Grand a réussi séparément avec la correction finale.
+
+Les durées ci-dessus sont celles des fixtures (préparation et lecture de milliers
+de blocs incluses), pas une mesure de FPS ni une promesse de durée de chargement.
+Les neuf graines/tailles de l’atlas ne constituent pas neuf visites complètes de
+structures. Les plafonds, reliefs et corps flottants restent ceux de 30.6.
+
+## Atlas et intégrité du terrain
+
+L’export natif final (3 min 42 s) a réussi pour les neuf couples
+512 / 724 / 1 024 × graines 0 / 42 / -7228211907433324401.
+Toutes les colonnes et coupes des quatre variantes sont **exactement égales** à
+l’export 30.6, avec les mêmes coordonnées et résolutions. La comparaison porte
+sur les tableaux de densité avant décoration, pas sur les matériaux enrichis ni
+sur les installations. Les empreintes des deux jeux de données sont archivées
+avec le rapport `density-306-307-comparison.json`.
+
+`./gradlew assemblePack -x :sanctuary:check` a réussi après le `check build` final.
+Le MRpack a été vérifié : version, dépendance exacte, tailles, empreintes, CRC,
+absence de sauvegardes personnelles et absence de second mécanisme de mise à jour.
+
+## Livraison
+
+Créer un **nouveau monde Sanctuary**. Le codec de prototype `sanctuary:island_v24`
+est conservé ; aucune migration ni régénération des sauvegardes n’est exécutée.
+Les réservations aériennes déjà enregistrées dans les anciens mondes sont gardées.
+Le pack reste sur Minecraft 26.3-pre-2, Fabric Loader 0.19.5 et Fabric API
+0.160.0+26.3. La réception publique et Prism est consignée dans `docs/packwiz.md`.

gradle.properties

@@ -8,6 +8,6 @@ loader_version=0.19.5
 loom_version=1.17.20
 fabric_api_version=0.160.0+26.3
 
-mod_version=0.1.0-alpha.30.6
-pack_version=0.1.0-alpha.30.6
+mod_version=0.1.0-alpha.30.7
+pack_version=0.1.0-alpha.30.7
 maven_group=fr.koka.sanctuary

mods/sanctuary/build.gradle

@@ -89,6 +89,11 @@ tasks.named('runGameTest') {
 
 tasks.named('processGametestResources') {
     def villageOnly = providers.gradleProperty('sanctuaryVillageOnly').map { it.toBoolean() }.getOrElse(false)
+    def focused = providers.gradleProperty('sanctuaryFocusedTests').getOrElse('').split(',').findAll { !it.isEmpty() }
+    def focusClasses = [aerial: 'Aerial24WorldGameTests', transit: 'Transit29WorldGameTests', village: 'Village306GameTests', drained: 'Drained307GameTests']
+    focused.each { if (!focusClasses.containsKey(it)) throw new GradleException('Unknown focused native test: ' + it) }
+    inputs.property('focusedNative', focused)
+
     inputs.property('villageOnly', villageOnly)
     def atlasOnly = providers.gradleProperty('sanctuaryAtlasOnly').map { it.toBoolean() }.getOrElse(false)
     inputs.property('atlasOnly', atlasOnly)
@@ -140,6 +145,10 @@ tasks.named('processGametestResources') {
             : unified ? 'fr.koka.sanctuary.gametest.UnifiedWorldGameTests'
             : 'fr.koka.sanctuary.gametest.SanctuaryWorldGameTests')
         if (atlasOnly || villageOnly) filter { line -> line.replaceAll(/("fabric-gametest": \["[^"]+")[^\]]*/, '$1') }
+        if (!focused.isEmpty()) filter { line ->
+            line.contains('"fabric-gametest":') ? '    "fabric-gametest": [' + focused.collect { '"fr.koka.sanctuary.gametest.' + focusClasses[it] + '"' }.join(', ') + '],' : line
+        }
+
     }
 }
 

mods/sanctuary/src/gametest/java/fr/koka/sanctuary/gametest/Aerial24WorldGameTests.java

@@ -69,9 +69,9 @@ public final class Aerial24WorldGameTests {
             helper.assertTrue(StructureCensusService.aerialSites(level).isEmpty(), "Disabled aerial sites are not presented as planned");
             report.put("passed", true); write(Path.of("diagnostics/aerial24/off.json"), report); helper.succeed(); return;
         }
-        helper.assertTrue(plan.sites().size() == 4, "All four initial aerial sites have a finite saved plan");
+        helper.assertTrue(plan.sites().size() == (generator.initialDiameter()==1024?5:4), "Both ships and all natural floating bodies have a saved plan");
         helper.assertTrue(plan.sites().stream().filter(AerialPlan24.Site::merchant).count() == 2, "Two merchant ships");
-        helper.assertTrue(plan.sites().stream().filter(AerialPlan24.Site::waterfall).count() == 1, "One waterfall site");
+        helper.assertTrue(plan.sites().stream().filter(AerialPlan24.Site::waterfall).count() == 0, "No artificial mineral-islet waterfall remains");
         if (generator.initialDiameter() == 724 && (level.getSeed() == 0 || level.getSeed() == 42))
             AerialRenderer24.writeDiagnostic(Path.of("diagnostics/aerial24/blocks.json"), plan.sites());
         report.put("geometry", JSON.toJsonTree(plan.sites())); report.put("claim_count", plan.claimsChunks().size());
@@ -121,6 +121,9 @@ public final class Aerial24WorldGameTests {
                 if (!tickets[0]) {
                     entityChunks.forEach(pos -> level.getChunkSource().addTicketWithRadius(TicketType.DRAGON, pos, 2)); tickets[0] = true;
                 }
+                // Other simultaneous fixtures may release a shared vanilla DRAGON ticket.
+                // Refresh our own still-required chunks until the lifecycle inspection completes.
+                entityChunks.forEach(pos -> level.getChunkSource().addTicketWithRadius(TicketType.DRAGON, pos, 2));
                 var occupants = occupants(level, plan);
                 var readiness = new TreeMap<String, Object>(); boolean entitiesReady = true;
                 for (var pos : entityChunks) {
@@ -171,7 +174,7 @@ public final class Aerial24WorldGameTests {
                 report.put("native_tags", tags); report.put("full_chunks", chunks.size());
                 report.put("blocks_after", countSites(level, plan));
                 var census = StructureCensusService.aerialSites(level);
-                helper.assertTrue(census.size() == 4 && census.stream().allMatch(site -> site.status() == StructureCensusService.AerialStatus.GENERATED),
+                helper.assertTrue(census.size() == plan.sites().size() && census.stream().allMatch(site -> site.status() == StructureCensusService.AerialStatus.GENERATED),
                     "Four historical generated sites remain indexed after loot, mining and demolition");
                 report.put("census_after", census);
                 helper.assertTrue(equalFiles(journalBefore, files(world.resolve("data").resolve(generator.journalDirectory()))), "Aerial tests never reserve or activate an expansion");
@@ -197,7 +200,7 @@ public final class Aerial24WorldGameTests {
                 double gap = AerialPlanner24.shoreDistance(site);
                 helper.assertTrue(gap >= 16 && gap <= 48, "Native ship is just off its verified shore");
                 helper.assertTrue(Math.abs(AerialGeometry24.entry(site).getY() - site.shoreY()) <= 4, "Boarding deck follows the nearby shore height");
-            } else {
+            } else if(site.kind()==AerialPlan24.Kind.MINERAL_ISLET) {
                 helper.assertTrue(root.ownsChunk(site.startChunkX(), site.startChunkZ()), "Mineral islet floats above Sanctuary terrain");
                 var column = generator.aerialBaseColumn24(site.shoreX(), site.shoreZ());
                 helper.assertTrue(column.getBlock(site.shoreY() - 1).isSolid(), "Overhead islet retains a real ground witness below it");
@@ -275,12 +278,12 @@ public final class Aerial24WorldGameTests {
                 helper.assertTrue(AerialRenderer24.loot(site).equals(chest.getLootTable()), "Aerial chest retains its unopened site-specific loot table");
                 for (var entry : model.entrySet()) if (!entry.getValue().isAir() && !entry.getValue().is(Blocks.WATER))
                     helper.assertTrue(level.getBlockState(entry.getKey()).is(entry.getValue().getBlock()), "Native FULL keeps authored material at " + site.id() + " " + entry.getKey());
-                for (var pos : AerialGeometry24.interiorChecks(site)) {
+                for (var pos : site.kind()==AerialPlan24.Kind.NATURAL_ISLET ? List.<BlockPos>of() : AerialGeometry24.interiorChecks(site)) {
                     helper.assertTrue(level.getBlockState(pos).getCollisionShape(level, pos).isEmpty()
                         && level.getBlockState(pos.above()).getCollisionShape(level, pos.above()).isEmpty(), "Usable two-block headroom at " + site.id());
                     helper.assertTrue(!level.getBlockState(pos.below()).getCollisionShape(level, pos.below()).isEmpty(), "Interior stands on a real floor");
                 }
-                if (site.kind() == AerialPlan24.Kind.MINERAL_ISLET) for (int dy = 1; dy <= 3; dy++)
+                if (!site.merchant()) for (int dy = 1; dy <= 3; dy++)
                     helper.assertTrue(level.getBlockState(chestAt.above(dy)).isSolid(), "Mineral chest needs excavation through three layers");
             } else helper.assertTrue(chest.getLootTable() == null && chest.isEmpty(), "Looted chest never refills on reload");
             if (site.kind() == AerialPlan24.Kind.MINERAL_ISLET)
@@ -299,9 +302,14 @@ public final class Aerial24WorldGameTests {
                 exterior.add(Map.of("position", coordinates(at), "observed_block", level.getBlockState(at).toString()));
             report.put(site.id() + "_exterior_observations", exterior);
         }
-        helper.assertTrue(chestCount == 4 && waterSources == 1, "Four physical chests and exactly one planned source");
+        helper.assertTrue(chestCount == plan.sites().size() && waterSources == 0, "One physical chest per site and no artificial waterfall");
         report.put("chests", chestCount); report.put("waterfall_sources", waterSources); report.put("blocks_before", countSites(level, plan));
         report.put("vegetation", vegetation);
+        if(fresh) for(var site:plan.sites()) if(site.kind()==AerialPlan24.Kind.NATURAL_ISLET) {
+            var blocks=countSites(level,plan).get(site.id());
+            for(String id:List.of("coal","iron","copper","gold","lapis","redstone","diamond","emerald"))
+                helper.assertTrue(blocks.getOrDefault("minecraft:"+id+"_ore",0)>0,"Finite "+id+" veins in "+site.id());
+        }
         return expected;
     }
 
@@ -359,8 +367,12 @@ public final class Aerial24WorldGameTests {
             for (int slot = 0; slot < chest.getContainerSize(); slot++) quantity += chest.getItem(slot).getCount();
             helper.assertTrue(quantity > 0, "Site-specific chest produces usable vanilla loot"); loot.put(site.id(), quantity);
             chest.clearContent(); chest.setChanged(); emptied.add(coordinates(at));
-            if (site.kind() == AerialPlan24.Kind.MINERAL_ISLET) {
-                var ores = models.get(site.id()).entrySet().stream().filter(entry -> ore(entry.getValue())).sorted(Map.Entry.comparingByKey(
+            if (!site.merchant()) {
+                var body = new HashMap<>(models.get(site.id()));
+                if(site.kind()==AerialPlan24.Kind.NATURAL_ISLET) for(var pos:BlockPos.betweenClosed(site.minX(),site.minY(),site.minZ(),site.maxX(),site.maxY(),site.maxZ())) {
+                    var state=level.getBlockState(pos); if(ore(state)) body.put(pos.immutable(),state);
+                }
+                var ores = body.entrySet().stream().filter(entry -> ore(entry.getValue())).sorted(Map.Entry.comparingByKey(
                     Comparator.<BlockPos>comparingInt(BlockPos::getX).thenComparingInt(BlockPos::getY).thenComparingInt(BlockPos::getZ))).limit(16).toList();
                 helper.assertTrue(!ores.isEmpty(), "Each mineral island contains actual finite veins");
                 for (var entry : ores) { level.setBlock(entry.getKey(), Blocks.AIR.defaultBlockState(), 2); removed.add(coordinates(entry.getKey())); }

mods/sanctuary/src/gametest/java/fr/koka/sanctuary/gametest/Drained307GameTests.java

@@ -0,0 +1,62 @@
+package fr.koka.sanctuary.gametest;
+
+import com.google.gson.GsonBuilder;
+import fr.koka.sanctuary.worldgen.SanctuaryChunkGenerator;
+import java.nio.file.*;
+import java.util.*;
+import net.fabricmc.fabric.api.gametest.v1.GameTest;
+import net.minecraft.core.BlockPos;
+import net.minecraft.core.registries.BuiltInRegistries;
+import net.minecraft.gametest.framework.GameTestHelper;
+import net.minecraft.world.level.chunk.status.ChunkStatus;
+import net.minecraft.world.level.levelgen.structure.StructureStart;
+import net.minecraft.world.level.levelgen.structure.pieces.StructurePieceSerializationContext;
+
+public final class Drained307GameTests {
+    @GameTest(maxTicks=12000)
+    public void nativeRuinsRemainDryAndKeepMarkers(GameTestHelper helper) throws Exception {
+        var level=helper.getLevel();var host=(SanctuaryChunkGenerator)level.getChunkSource().getGenerator();
+        if(host.rootGeneration()!=24){helper.succeed();return;}
+        var plans=host.dryRuins307();
+        if(!level.structureManager().shouldGenerateStructures()||!host.experimentalStructures()) {
+            helper.assertTrue(plans.isEmpty(),"Disabled structures reserve no dry ruins");helper.succeed();return;
+        }
+        var report=new LinkedHashMap<String,Object>();report.put("seed",Long.toString(level.getSeed()));report.put("diameter",host.initialDiameter());
+        report.put("planned",plans.size());report.put("bounds",plans.stream().map(s->s.getBoundingBox().toString()).toList());
+        Path out=Path.of("diagnostics/drained307",host.initialDiameter()+"-"+level.getSeed()+".json");Files.createDirectories(out.getParent());
+        Files.writeString(out,new GsonBuilder().setPrettyPrinting().create().toJson(report));
+        if(Boolean.getBoolean("sanctuary.test.village306.planOnly")) {helper.succeed();return;}
+        var chunks=new LinkedHashSet<net.minecraft.world.level.ChunkPos>();plans.forEach(s->s.getBoundingBox().intersectingChunks().forEach(chunks::add));
+        var iterator=chunks.iterator();Runnable[] step=new Runnable[1];boolean[] tickets={false};int[] wait={0};
+        step[0]=()->{try {
+            if(iterator.hasNext()) {var cp=iterator.next();level.getChunk(cp.x(),cp.z(),ChunkStatus.FULL,true);helper.runAtTickTime(helper.getTick()+1,()->step[0].run());return;}
+            if(!tickets[0]){chunks.forEach(cp->level.getChunkSource().addTicketWithRadius(net.minecraft.server.level.TicketType.DRAGON,cp,2));tickets[0]=true;}
+            if(wait[0]++<40){helper.runAtTickTime(helper.getTick()+1,()->step[0].run());return;}
+            var counts=new TreeMap<String,Integer>();var saved=new ArrayList<String>();int zombies=0,chests=0,corals=0;
+            var ctx=StructurePieceSerializationContext.fromLevel(level);
+            for(var planned:plans) {
+                var cp=planned.getChunkPos();var actual=level.getChunk(cp.x(),cp.z()).getStartForStructure(planned.getStructure());
+                helper.assertTrue(actual!=null&&actual.isValid(),"Dry ruin has a native start");
+                var tag=actual.createTag(ctx,cp);var restored=StructureStart.loadStaticStart(ctx,tag,level.getSeed());
+                helper.assertTrue(restored!=null&&tag.equals(restored.createTag(ctx,cp)),"Ruin floor, orientation, seed and occupant flags survive native serialization");
+                saved.add(tag.toString());var box=planned.getBoundingBox();
+                for(var at:BlockPos.betweenClosed(box.minX(),box.minY(),box.minZ(),box.maxX(),box.maxY(),box.maxZ())) {
+                    var state=level.getBlockState(at);var id=BuiltInRegistries.BLOCK.getKey(state.getBlock()).toString();
+                    if(!state.isAir())counts.merge(id,1,Integer::sum);
+                    helper.assertTrue(state.getFluidState().isEmpty(),"Drained ruin has no water or waterlogged block at "+at);
+                    if(id.contains("dead_")&&id.contains("coral"))corals++;
+                    if(level.getBlockEntity(at) instanceof net.minecraft.world.level.block.entity.RandomizableContainerBlockEntity chest) {
+                        chests++;helper.assertTrue(net.minecraft.world.level.storage.loot.BuiltInLootTables.UNDERWATER_RUIN_SMALL.equals(chest.getLootTable()),"Native ocean loot retained");
+                    }
+                }
+                var inhabitants=level.getEntitiesOfClass(net.minecraft.world.entity.monster.zombie.Zombie.class,net.minecraft.world.phys.AABB.of(box).inflate(8));
+                zombies+=inhabitants.stream().filter(z->z.isPersistenceRequired()).count();
+            }
+            report.put("blocks",counts);report.put("chests",chests);report.put("dead_corals",corals);report.put("persistent_zombies",zombies);report.put("saved_starts",saved);
+            if(!plans.isEmpty()) {helper.assertTrue(chests>0,"Native treasure marker placed");helper.assertTrue(corals>0,"Dead coral accents present");helper.assertTrue(zombies>0,"Persistent vanilla zombie occupants present");}
+            report.put("passed",true);Files.writeString(out,new GsonBuilder().setPrettyPrinting().create().toJson(report));
+            chunks.forEach(cp->level.getChunkSource().removeTicketWithRadius(net.minecraft.server.level.TicketType.DRAGON,cp,2));helper.succeed();
+        }catch(Exception e){throw new IllegalStateException(e);}};
+        helper.runAtTickTime(helper.getTick()+1,()->step[0].run());
+    }
+}

mods/sanctuary/src/gametest/java/fr/koka/sanctuary/gametest/Transit29WorldGameTests.java

@@ -39,9 +39,9 @@ public final class Transit29WorldGameTests {
             }
             helper.assertFalse(plan.isEmpty(), "A structures-enabled Sanctuary world must retain its main traversal: " + plan.diagnostic());
             var accesses = plan.modules().stream().filter(m -> m.kind() == TransitPlan21.Kind.ACCESS).toList();
-            helper.assertTrue(accesses.size() == 2, "The complete traversal has two independent surface accesses");
-            int span = Math.max(Math.abs(accesses.getFirst().centerX() - accesses.getLast().centerX()),
-                Math.abs(accesses.getFirst().centerZ() - accesses.getLast().centerZ()));
+            helper.assertTrue(List.of(2,4).contains(accesses.size()), "The complete traversal has two independent surface accesses");
+            int span = Math.max(Math.abs(accesses.getFirst().centerX() - accesses.get(1).centerX()),
+                Math.abs(accesses.getFirst().centerZ() - accesses.get(1).centerZ()));
             helper.assertTrue(span >= generator.initialDiameter() / 4, "The main route spans at least a quarter of the island diameter");
             report.put("span", span);
             var holder = level.registryAccess().lookupOrThrow(Registries.STRUCTURE).getOrThrow(TransitStructures21.KEY);
@@ -72,7 +72,7 @@ public final class Transit29WorldGameTests {
                         for (int z = module.minZ() - 3; z < module.minZ(); z++) chunks.add(new ChunkPos(x >> 4, z >> 4));
                 }
             }
-            helper.assertTrue(chunks.size() <= 160, "The native traversal witness stays inside its bounded footprint");
+            helper.assertTrue(chunks.size() <= 320, "The native traversal witness stays inside its bounded footprint");
             report.put("local_starts", starts.size()); report.put("planned_footprint_chunks", chunks.size());
             boolean planOnly = Boolean.getBoolean("sanctuary.test.transit29.planOnly");
             report.put("plan_only", planOnly);
@@ -107,7 +107,18 @@ public final class Transit29WorldGameTests {
                             }
                     report.put("closed_wall_checks", closedWallChecks);
                     report.put("module_biomes", biomes);
-                    report.put("walk", Transit21WorldGameTests.verifyAccess(helper, plan));
+                    var walks=new ArrayList<Object>();
+                    var remaining=new ArrayList<>(plan.modules());
+                    while(!remaining.isEmpty()) {
+                        var group=new ArrayList<TransitPlan21.Module>();group.add(remaining.removeFirst());
+                        boolean grew;
+                        do {grew=false;for(var candidate:List.copyOf(remaining)) if(group.stream().anyMatch(m->
+                            m.minX()<=candidate.maxX()+1&&m.maxX()+1>=candidate.minX()&&m.minZ()<=candidate.maxZ()+1&&m.maxZ()+1>=candidate.minZ())) {
+                                group.add(candidate);remaining.remove(candidate);grew=true;
+                            }}while(grew);
+                        walks.add(Transit21WorldGameTests.verifyAccess(helper,new TransitPlan21(group,0,"accepted29 native component")));
+                    }
+                    report.put("walk",walks);
                     var nearest = TransitStructures21.findNearest(level, HolderSet.direct(holder), net.minecraft.core.BlockPos.ZERO, 128, false);
                     helper.assertTrue(nearest != null && accesses.stream().anyMatch(m -> TransitPiece21.locator(m).equals(nearest.getFirst())),
                         "The real structure locator returns one of the walkable surface gates");

mods/sanctuary/src/gametest/resources/fabric.mod.json

@@ -6,7 +6,7 @@
   "environment": "*",
   "license": "GPL-3.0-or-later",
   "entrypoints": {
-    "fabric-gametest": ["${gametest_entrypoint}", "fr.koka.sanctuary.gametest.Swamp27WorldGameTests", "fr.koka.sanctuary.gametest.Caves28WorldGameTests", "fr.koka.sanctuary.gametest.Terraces29WorldGameTests", "fr.koka.sanctuary.gametest.River30WorldGameTests", "fr.koka.sanctuary.gametest.Transit29WorldGameTests", "fr.koka.sanctuary.gametest.Alpha28NativeStructuresGameTests", "fr.koka.sanctuary.gametest.Village306GameTests", "fr.koka.sanctuary.gametest.BlockKnowledgeGameTests", "fr.koka.sanctuary.gametest.CensusGameTestsTerrain", "fr.koka.sanctuary.gametest.CensusStockGameTests", "fr.koka.sanctuary.gametest.MaterialActivityGameTests"],
+    "fabric-gametest": ["${gametest_entrypoint}", "fr.koka.sanctuary.gametest.Swamp27WorldGameTests", "fr.koka.sanctuary.gametest.Caves28WorldGameTests", "fr.koka.sanctuary.gametest.Terraces29WorldGameTests", "fr.koka.sanctuary.gametest.River30WorldGameTests", "fr.koka.sanctuary.gametest.Transit29WorldGameTests", "fr.koka.sanctuary.gametest.Alpha28NativeStructuresGameTests", "fr.koka.sanctuary.gametest.Village306GameTests", "fr.koka.sanctuary.gametest.Drained307GameTests", "fr.koka.sanctuary.gametest.BlockKnowledgeGameTests", "fr.koka.sanctuary.gametest.CensusGameTestsTerrain", "fr.koka.sanctuary.gametest.CensusStockGameTests", "fr.koka.sanctuary.gametest.MaterialActivityGameTests"],
     "fabric-client-gametest": ["fr.koka.sanctuary.gametest.SanctuaryClientRenderTests"]
   },
   "mixins": ["sanctuary-gametest.mixins.json"],

mods/sanctuary/src/main/java/fr/koka/sanctuary/SanctuaryMod.java

@@ -80,6 +80,7 @@ public final class SanctuaryMod implements ModInitializer {
         Registry.register(BuiltInRegistries.BIOME_SOURCE, id("island_v24"), SanctuaryBiomeSource.AERIAL24_CODEC);
         fr.koka.sanctuary.worldgen.aerial.AerialStructures24.register();
         fr.koka.sanctuary.worldgen.underground306.Village306.register();
+        fr.koka.sanctuary.worldgen.drained307.DryOcean307.register();
         fr.koka.sanctuary.worldgen.mineral.MineralSanctuaryStructures23.register();
         fr.koka.sanctuary.worldgen.transit.TransitStructures21.register();
         fr.koka.sanctuary.worldgen.city.LostCityUndergroundStructures22.register();

mods/sanctuary/src/main/java/fr/koka/sanctuary/expansion/ExpansionChunkGenerator.java

@@ -138,6 +138,12 @@ public class ExpansionChunkGenerator extends ChunkGenerator {
                 if (existing == null || !existing.isValid()) structures.setStartForStructure(planned.getStructure(), planned, chunk);
             }
         }
+        if (this instanceof fr.koka.sanctuary.worldgen.SanctuaryChunkGenerator host && structures.shouldGenerateStructures() && Level.OVERWORLD.equals(dimension)) {
+            for (var planned : host.dryRuins307()) if (planned.getChunkPos().equals(chunk.getPos())) {
+                var existing = structures.getStartForStructure(planned.getStructure(), chunk);
+                if (existing == null || !existing.isValid()) structures.setStartForStructure(planned.getStructure(), planned, chunk);
+            }
+        }
         ExpansionStructures.generate(this, registries, state, structures, chunk, templates, dimension);
     }
     @Override public void spawnOriginalMobs(WorldGenRegion region) {

mods/sanctuary/src/main/java/fr/koka/sanctuary/expansion/ExpansionStructures23.java

@@ -554,6 +554,7 @@ public final class ExpansionStructures23 {
         if (generator.village306().start() != null) {
             var village = generator.village306().start().getChunkPos(); addPosition(positions, village.x(), village.z());
         }
+        generator.dryRuins307().forEach(s -> addPosition(positions, s.getChunkPos().x(), s.getChunkPos().z()));
         var mineral = generator.mineralSanctuary23();
         if (!mineral.isEmpty()) addPosition(positions, mineral.chamber().startChunkX(), mineral.chamber().startChunkZ());
         if (generator.rootGeneration() == 24) generator.aerialPlan24().sites()

mods/sanctuary/src/main/java/fr/koka/sanctuary/mixin/UnifiedDecorationProtectionMixin.java

@@ -21,6 +21,10 @@ public abstract class UnifiedDecorationProtectionMixin {
         if (!(region.getLevel().getChunkSource().getGenerator() instanceof SanctuaryChunkGenerator generator)
                 || !fr.koka.sanctuary.expansion.ExpansionIsland.spatialGeneration(generator.rootGeneration())) return;
         // Aerial pieces write in genuine void chunks, within their own immutable site and current chunk only.
+        if (fr.koka.sanctuary.worldgen.drained307.DryOcean307.isPlacing()) {
+            if (!fr.koka.sanctuary.worldgen.drained307.DryOcean307.mayWrite(pos)) callback.setReturnValue(false);
+            return;
+        }
         if (fr.koka.sanctuary.worldgen.underground306.Village306.isPlacing()) {
             if (!fr.koka.sanctuary.worldgen.underground306.Village306.mayWrite(pos)) callback.setReturnValue(false);
             return;
@@ -48,6 +52,10 @@ public abstract class UnifiedDecorationProtectionMixin {
         if (!(region.getLevel().getChunkSource().getGenerator() instanceof SanctuaryChunkGenerator generator)) return;
         // Vanilla rejects writes outside its region before reading the destination chunk.
         if (!region.isWithinWriteZone(pos)) return;
+        if (fr.koka.sanctuary.worldgen.drained307.DryOcean307.isPlacing()) {
+            if (!fr.koka.sanctuary.worldgen.drained307.DryOcean307.mayWrite(pos)) callback.setReturnValue(false);
+            return;
+        }
         if (fr.koka.sanctuary.worldgen.underground306.Village306.isPlacing()) {
             if (!fr.koka.sanctuary.worldgen.underground306.Village306.mayWrite(pos)) callback.setReturnValue(false);
             return;
@@ -56,6 +64,11 @@ public abstract class UnifiedDecorationProtectionMixin {
             if (!fr.koka.sanctuary.worldgen.aerial.AerialStructures24.mayWrite(pos)) callback.setReturnValue(false);
             return;
         }
+        // Native vegetation patches may call setBlock without ensureCanWrite, including
+        // from a neighbouring chunk after this ruin was placed. Preserve its dry footprint.
+        if (generator.protectsDryRuin307(pos)) {
+            callback.setReturnValue(false); return;
+        }
         if ((generator.rootGeneration() == 23 || generator.rootGeneration() == 24)) {
             if (fr.koka.sanctuary.worldgen.mineral.MineralSanctuaryStructures23.isPlacing()) return;
             var island = generator.islandAt(pos.getX(), pos.getZ());

mods/sanctuary/src/main/java/fr/koka/sanctuary/worldgen/SanctuaryChunkGenerator.java

@@ -104,6 +104,16 @@ public final class SanctuaryChunkGenerator extends ExpansionChunkGenerator {
         prepareHeritage(root);
         prepareTransit(root);
     }
+    public java.util.List<FloatingTerrain306.Mass> naturalMasses306(ServerLevel level) {
+        int players=initialDiameter()==512?5:initialDiameter()==724?10:20;
+        var field=level.registryAccess().lookupOrThrow(net.minecraft.core.registries.Registries.DENSITY_FUNCTION)
+            .getOrThrow(net.minecraft.resources.ResourceKey.create(net.minecraft.core.registries.Registries.DENSITY_FUNCTION,
+                SanctuaryMod.id("population_"+players))).value();
+        var sampler=originContext.random().getSampler(field);
+        if(sampler instanceof DetachedRock302 detached) sampler=detached.input();
+        if(!(sampler instanceof FloatingTerrain306 floating)) throw new IllegalStateException("Missing natural upper terrain sampler");
+        return floating.masses(net.minecraft.world.level.levelgen.densityfunction.SamplerContext.builder().enableCaches().build());
+    }
     public net.minecraft.world.level.NoiseColumn aerialBaseColumn24(int x, int z) {
         var current = originContext;
         if (current == null || heightAccessor == null) throw new IllegalStateException("Aerial sampling before world attachment");
@@ -140,6 +150,12 @@ public final class SanctuaryChunkGenerator extends ExpansionChunkGenerator {
     private volatile fr.koka.sanctuary.worldgen.underground306.Village306.Plan village306 = fr.koka.sanctuary.worldgen.underground306.Village306.Plan.EMPTY;
     private boolean villagePrepared306;
     private boolean minesPrepared306;
+    private boolean dryRuinsPrepared307;
+    private volatile java.util.List<net.minecraft.world.level.levelgen.structure.StructureStart> dryRuins307 = java.util.List.of();
+    public java.util.List<net.minecraft.world.level.levelgen.structure.StructureStart> dryRuins307() { return dryRuins307; }
+    public boolean protectsDryRuin307(net.minecraft.core.BlockPos pos) {
+        return dryRuins307.stream().anyMatch(s -> s.getBoundingBox().isInside(pos));
+    }
     private volatile java.util.List<fr.koka.sanctuary.expansion.ExpansionStructures23.Accepted> starterMines306 = java.util.List.of();
     public java.util.List<fr.koka.sanctuary.expansion.ExpansionStructures23.Accepted> starterMines306() { return starterMines306; }
     public fr.koka.sanctuary.worldgen.underground306.Village306.Plan village306() { return village306; }
@@ -196,6 +212,7 @@ public final class SanctuaryChunkGenerator extends ExpansionChunkGenerator {
     public fr.koka.sanctuary.worldgen.heritage.HeritagePlan19 heritagePlan19() { return heritagePlan19; }
     public boolean intersectsExperimentalStructures(int minX, int minY, int minZ, int maxX, int maxY, int maxZ) {
         if (village306.intersects(minX,minY,minZ,maxX,maxY,maxZ)) return true;
+        for (var ruin : dryRuins307) if (ruin.getBoundingBox().intersects(new net.minecraft.world.level.levelgen.structure.BoundingBox(minX,minY,minZ,maxX,maxY,maxZ))) return true;
         for (var mine : starterMines306) for(var piece : mine.start().getPieces())
             if(piece.getBoundingBox().intersects(new net.minecraft.world.level.levelgen.structure.BoundingBox(minX,minY,minZ,maxX,maxY,maxZ))) return true;
         if (generation == 24) for (var site : aerialPlan24.sites()) {
@@ -263,6 +280,10 @@ public final class SanctuaryChunkGenerator extends ExpansionChunkGenerator {
             minesPrepared306 = true;
             starterMines306 = fr.koka.sanctuary.expansion.ExpansionStructures23.starterMines306(level,this,islands.stream().filter(ExpansionIsland::origin).findFirst().orElseThrow());
         }
+        if (!dryRuinsPrepared307 && generation == 24 && cityStructuresEnabled && experimentalStructures) {
+            dryRuinsPrepared307 = true;
+            dryRuins307 = fr.koka.sanctuary.worldgen.drained307.DryOcean307.plan(level, this);
+        }
     }
     @Override public void setIslands(List<ExpansionIsland> islands) {
         // Complete and publish city geometry before workers can observe the new owner list.
@@ -372,7 +393,7 @@ public final class SanctuaryChunkGenerator extends ExpansionChunkGenerator {
                 || ruinsPlan17.protects(pos.getX(), pos.getY(), pos.getZ()) || heritagePlan19.protects(pos.getX(), pos.getY(), pos.getZ()));
         long start = System.nanoTime();
         transitPlan21 = generation == 24
-            ? fr.koka.sanctuary.worldgen.transit.TransitPlanner29.plan(root.seed(), root.centerX(), root.centerZ(), root.diameter(), sampled)
+            ? fr.koka.sanctuary.worldgen.transit.TransitPlanner29.plan307(root.seed(), root.centerX(), root.centerZ(), root.diameter(), sampled)
             : generation >= 22
             ? fr.koka.sanctuary.worldgen.transit.TransitPlanner22.plan(root.seed(), root.centerX(), root.centerZ(), root.diameter(), sampled)
             : fr.koka.sanctuary.worldgen.transit.TransitPlanner21.plan(root.seed(), root.centerX(), root.centerZ(), root.diameter(), sampled);
@@ -570,6 +591,7 @@ public final class SanctuaryChunkGenerator extends ExpansionChunkGenerator {
     }
     public boolean protectsCityDecoration(net.minecraft.core.BlockPos pos) {
         if (village306.cavern() != null && village306.cavern().getBoundingBox().isInside(pos)) return true;
+        for (var ruin : dryRuins307) if (ruin.getBoundingBox().isInside(pos)) return true;
         if (generation == 24 && aerialPlan24.protects(pos)) return true;
         if ((generation == 23 || generation == 24) && mineralSanctuary23.protects(pos.getX(), pos.getY(), pos.getZ())) return true;
         if (generation == 16 || generation == 17 || generation == 19 || generation == 20 || generation == 21 || generation == 22 || (generation == 23 || generation == 24)) return cityProtection16.contains(pos.getX(), pos.getY(), pos.getZ())

mods/sanctuary/src/main/java/fr/koka/sanctuary/worldgen/aerial/AerialGeometry24.java

@@ -15,6 +15,7 @@ public final class AerialGeometry24 {
     public static BlockPos chest(AerialPlan24.Site s) {
         return switch (s.kind()) {
             case MERCHANT_PROVISIONS, MERCHANT_TOOLS -> world(s, 7, 4, 24);
+            case NATURAL_ISLET -> world(s, s.width()/2, s.height()/2, s.depth()/2);
             case MINERAL_ISLET -> {
                 int x = s.width() / 2 + 4, z = s.depth() / 2 + 2;
                 yield world(s, x, terrainTop(s, x, z) - 3, z);
@@ -37,6 +38,7 @@ public final class AerialGeometry24 {
     public static BlockPos entry(AerialPlan24.Site s) {
         return switch (s.kind()) {
             case MERCHANT_PROVISIONS, MERCHANT_TOOLS -> world(s, 3, 5, 13);
+            case NATURAL_ISLET -> chest(s);
             case MINERAL_ISLET -> world(s, s.width() / 2, terrainTop(s, s.width() / 2, s.depth() / 2) + 1, s.depth() / 2);
         };
     }

mods/sanctuary/src/main/java/fr/koka/sanctuary/worldgen/aerial/AerialPiece24.java

@@ -75,6 +75,7 @@ public final class AerialPiece24 extends StructurePiece {
     @Override public void postProcess(WorldGenLevel level, StructureManager manager, ChunkGenerator generator,
             RandomSource random, BoundingBox clip, ChunkPos chunk, BlockPos pivot) {
         AerialStructures24.placing(site, () -> {
+            if(site.kind()==AerialPlan24.Kind.NATURAL_ISLET) NaturalIslet307.enrich(level,site,clip);
             AerialRenderer24.render(site, new LostCityRenderer.BlockWriter() {
                 private BlockPos position(int x, int y, int z) { return new BlockPos(site.minX() + x, site.minY() + y, site.minZ() + z); }
                 @Override public void set(int x, int y, int z, BlockState state) {

mods/sanctuary/src/main/java/fr/koka/sanctuary/worldgen/aerial/AerialPlan24.java

@@ -19,16 +19,19 @@ public final class AerialPlan24 {
     private final List<Site> sites;
     private final Set<Long> claims;
 
-    public enum Kind { MERCHANT_PROVISIONS, MERCHANT_TOOLS, MINERAL_ISLET }
+    public enum Kind { MERCHANT_PROVISIONS, MERCHANT_TOOLS, MINERAL_ISLET, NATURAL_ISLET }
 
     public AerialPlan24(List<Site> sites) {
         this.sites = List.copyOf(sites);
-        if (!sites.isEmpty() && (sites.size() != 4
-                || sites.stream().filter(s -> s.kind() == Kind.MERCHANT_PROVISIONS).count() != 1
-                || sites.stream().filter(s -> s.kind() == Kind.MERCHANT_TOOLS).count() != 1
-                || sites.stream().filter(s -> s.kind() == Kind.MINERAL_ISLET).count() != 2
-                || sites.stream().filter(Site::waterfall).count() != 1))
-            throw new IllegalArgumentException("An aerial plan contains all four sites and exactly one waterfall, or is disabled");
+        boolean legacy = sites.size()==4 && sites.stream().filter(s -> s.kind()==Kind.MINERAL_ISLET).count()==2
+            && sites.stream().filter(Site::waterfall).count()==1;
+        boolean natural = (sites.size()==4 || sites.size()==5)
+            && sites.stream().filter(s -> s.kind()==Kind.NATURAL_ISLET).count()==sites.size()-2
+            && sites.stream().noneMatch(Site::waterfall);
+        if (!sites.isEmpty() && (!(legacy || natural)
+            || sites.stream().filter(s -> s.kind()==Kind.MERCHANT_PROVISIONS).count()!=1
+            || sites.stream().filter(s -> s.kind()==Kind.MERCHANT_TOOLS).count()!=1))
+            throw new IllegalArgumentException("Incomplete aerial sites");
         var ids = new HashSet<String>();
         var columns = new HashSet<Long>();
         for (Site site : sites) {
@@ -55,7 +58,8 @@ public final class AerialPlan24 {
         }
         return false;
     }
-    public boolean protects(BlockPos pos) { return sites.stream().anyMatch(s -> s.mayWrite(pos)); }
+    public boolean protects(BlockPos pos) { return sites.stream().anyMatch(s -> s.kind()==Kind.NATURAL_ISLET
+        ? AerialGeometry24.chest(s).distManhattan(pos)<=2 : s.mayWrite(pos)); }
 
     /** Width and depth are local dimensions; facing rotates them around the world-space bounding-box minimum. */
     public record Site(String id, Kind kind, int minX, int minY, int minZ, int width, int height, int depth,
@@ -64,8 +68,8 @@ public final class AerialPlan24 {
             if (id == null || !id.matches("[a-z][a-z0-9_]{0,47}") || kind == null || facing < 0 || facing > 3
                     || Math.abs((long) minX) > 2048 || Math.abs((long) minZ) > 2048
                     || Math.abs((long) shoreX) > 1024 || Math.abs((long) shoreZ) > 1024
-                    || shoreY < 1 || shoreY > 383 || minY < 32 || height < 8 || height > 35 + VEGETATION_HEADROOM || minY + height > 350
-                    || width < 7 || width > 64 || depth < 7 || depth > 64
+                    || shoreY < 1 || shoreY > 383 || minY < 32 || height < 8 || height > (kind==Kind.NATURAL_ISLET ? 110 : 35 + VEGETATION_HEADROOM) || minY + height > (kind==Kind.NATURAL_ISLET ? 430 : 350)
+                    || width < 7 || width > (kind==Kind.NATURAL_ISLET ? 136 : 64) || depth < 7 || depth > (kind==Kind.NATURAL_ISLET ? 136 : 64)
                     || waterfall && kind != Kind.MINERAL_ISLET)
                 throw new IllegalArgumentException("Invalid aerial site geometry");
             if (kind == Kind.MINERAL_ISLET && (width < 40 || depth < 40 || height < 20 + VEGETATION_HEADROOM)

mods/sanctuary/src/main/java/fr/koka/sanctuary/worldgen/aerial/AerialPlanner24.java

@@ -38,10 +38,14 @@ public final class AerialPlanner24 {
             @Override public boolean reserved(int x, int z, int minY, int maxY) {
                 return generator.intersectsExperimentalStructures(x, minY, z, x, maxY, z);
             }
-        });
+        }, generator.naturalMasses306(level));
     }
 
     public static AerialPlan24 plan(long seed, int diameter, Terrain terrain) {
+        return plan(seed,diameter,terrain,null);
+    }
+    private static AerialPlan24 plan(long seed,int diameter,Terrain terrain,
+            java.util.List<fr.koka.sanctuary.worldgen.FloatingTerrain306.Mass> natural) {
         if (diameter != 512 && diameter != 724 && diameter != 1024) throw new IllegalArgumentException("Unsupported aerial root size");
         int radius = diameter == 724 ? 395 : diameter / 2 + 32;
         var probe = new Probe(terrain, radius);
@@ -50,7 +54,7 @@ public final class AerialPlanner24 {
         Kind[] kinds = {Kind.MERCHANT_PROVISIONS, Kind.MERCHANT_TOOLS, Kind.MINERAL_ISLET, Kind.MINERAL_ISLET};
         String[] ids = {"merchant_provisions", "merchant_tools", "mineral_islet_water", "mineral_islet_dry"};
         double initialAngle = unit(mix(seed ^ 0xA24AE21AL)) * Math.PI * 2;
-        for (int ordinal = 0; ordinal < kinds.length; ordinal++) {
+        for (int ordinal = 0; ordinal < (natural==null ? kinds.length : 2); ordinal++) {
             long siteSeed = ExpansionIsland.deriveSeed(seed ^ 0xA24AE21AL, ids[ordinal]);
             boolean merchant = ordinal < 2;
             int width = merchant ? 11 : 40 + 4 * (int) Math.floorMod(siteSeed, 7);
@@ -153,6 +157,26 @@ public final class AerialPlanner24 {
             sites.add(accepted);
             accepted.claimedChunks().forEach(c -> claimed.add(c.pack()));
         }
+        if(natural!=null) {
+            if(natural.size()!=(diameter==1024?3:2)) throw new IllegalStateException("Missing natural upper terrain");
+            for(int i=0;i<natural.size();i++) {
+                var m=natural.get(i);
+                var coast=shore(probe,Math.atan2(m.z(),m.x()),radius);
+                if(coast==null) throw new IllegalStateException("No shore witness for natural islet");
+                int rx=(int)Math.ceil(m.rx()*1.8),rz=(int)Math.ceil(m.rz()*1.8),half=(int)Math.ceil(m.depth()*1.5);
+                var site=new Site("natural_islet_"+i,Kind.NATURAL_ISLET,m.x()-rx,m.y()-half,m.z()-rz,
+                    rx*2+1,half*2+1,rz*2+1,0,ExpansionIsland.deriveSeed(seed,"natural_islet_"+i),
+                    coast.x,coast.y,coast.z,false);
+                // A chest replaces one existing rock block; the surrounding body must already exist.
+                var chest=AerialGeometry24.chest(site);
+                for(int dx=-1;dx<=1;dx++)for(int dz=-1;dz<=1;dz++)for(int dy=-1;dy<=2;dy++)
+                    if(!probe.column(chest.getX()+dx,chest.getZ()+dz).getBlock(chest.getY()+dy).isSolid())
+                        throw new IllegalStateException("Natural treasure has no stable rock cover: "+site.id());
+                if(site.claimedChunks().stream().anyMatch(c->claimed.contains(c.pack())))
+                    throw new IllegalStateException("Natural treasure reservation overlaps another aerial site");
+                sites.add(site);site.claimedChunks().forEach(c->claimed.add(c.pack()));
+            }
+        }
         var result = new AerialPlan24(sites);
         System.getLogger(AerialPlanner24.class.getName()).log(System.Logger.Level.INFO,
             "Aerial24 seed=" + seed + " diameter=" + diameter + " sites=" + result.sites().size()

mods/sanctuary/src/main/java/fr/koka/sanctuary/worldgen/aerial/AerialRenderer24.java

@@ -60,7 +60,7 @@ public final class AerialRenderer24 {
         return Map.copyOf(blocks);
     }
     public static ResourceKey<LootTable> loot(AerialPlan24.Site s) {
-        return ResourceKey.create(Registries.LOOT_TABLE, SanctuaryMod.id("chests/aerial24/" + s.kind().name().toLowerCase(java.util.Locale.ROOT)));
+        return ResourceKey.create(Registries.LOOT_TABLE, SanctuaryMod.id("chests/aerial24/" + (s.kind()==AerialPlan24.Kind.NATURAL_ISLET ? "mineral_islet" : s.kind().name().toLowerCase(java.util.Locale.ROOT))));
     }
     public static void render(AerialPlan24.Site s, LostCityRenderer.BlockWriter out) { render(s, out, s.bounds()); }
     public static void render(AerialPlan24.Site s, LostCityRenderer.BlockWriter out, BoundingBox clip) {
@@ -74,12 +74,13 @@ public final class AerialRenderer24 {
                 if (clip.isInside(s.minX() + x, s.minY() + y, s.minZ() + z)) out.chest(x, y, z, table, seed);
             }
         };
-        var connected = s.kind() == AerialPlan24.Kind.MINERAL_ISLET ? null : ConnectedBlocks20.buffer(clipped);
+        var connected = !s.merchant() ? null : ConnectedBlocks20.buffer(clipped);
         var destination = connected == null ? clipped : connected;
         var b = new Builder(s, destination, connected == null ? clip : s.bounds());
         switch (s.kind()) {
             case MERCHANT_PROVISIONS, MERCHANT_TOOLS -> b.ship();
             case MINERAL_ISLET -> b.islet();
+            case NATURAL_ISLET -> { /* Existing density owns the whole natural silhouette. */ }
         }
         var chest = AerialGeometry24.chest(s);
         destination.chest(chest.getX() - s.minX(), chest.getY() - s.minY(), chest.getZ() - s.minZ(), loot(s), s.seed() ^ 0x24C4E57L);

mods/sanctuary/src/main/java/fr/koka/sanctuary/worldgen/aerial/AerialStructures24.java

@@ -36,10 +36,10 @@ public final class AerialStructures24 {
     private static ResourceKey<Structure> key(String id) { return ResourceKey.create(Registries.STRUCTURE, SanctuaryMod.id(id)); }
     public static void register() {}
     public static String family(AerialPlan24.Site site) {
-        return switch (site.kind()) { case MINERAL_ISLET -> "mineral_islet"; default -> "merchant_ship"; };
+        return switch (site.kind()) { case MINERAL_ISLET, NATURAL_ISLET -> "mineral_islet"; default -> "merchant_ship"; };
     }
     public static ResourceKey<Structure> key(AerialPlan24.Site site) {
-        return switch (site.kind()) { case MINERAL_ISLET -> MINERAL_ISLET; default -> MERCHANT_SHIP; };
+        return switch (site.kind()) { case MINERAL_ISLET, NATURAL_ISLET -> MINERAL_ISLET; default -> MERCHANT_SHIP; };
     }
     public static String structureId(AerialPlan24.Site site) { return key(site).identifier().toString(); }
     public static boolean isPlacing() { return PLACING.get() != null; }

mods/sanctuary/src/main/java/fr/koka/sanctuary/worldgen/aerial/NaturalIslet307.java

@@ -0,0 +1,39 @@
+package fr.koka.sanctuary.worldgen.aerial;
+
+import net.minecraft.core.BlockPos;
+import net.minecraft.tags.BlockTags;
+import net.minecraft.world.level.WorldGenLevel;
+import net.minecraft.world.level.block.Block;
+import net.minecraft.world.level.block.Blocks;
+import net.minecraft.world.level.levelgen.structure.BoundingBox;
+
+/** Finite seams replace only the existing rock. The accepted30.6 density is untouched. */
+public final class NaturalIslet307 {
+    private NaturalIslet307() {}
+    public static void enrich(WorldGenLevel level,AerialPlan24.Site site,BoundingBox clip) {
+        for(int x=Math.max(site.minX(),clip.minX());x<=Math.min(site.maxX(),clip.maxX());x++)
+            for(int z=Math.max(site.minZ(),clip.minZ());z<=Math.min(site.maxZ(),clip.maxZ());z++) {
+                int top=-1,bottom=-1;
+                for(int y=Math.min(399,site.maxY());y>=Math.max(300,site.minY());y--) {
+                    var state=level.getBlockState(new BlockPos(x,y,z));
+                    if(state.is(BlockTags.BASE_STONE_OVERWORLD)) {if(top<0)top=y;bottom=y;}
+                }
+                if(top<0)continue;
+                for(int y=bottom;y<=top;y++) {
+                    var at=new BlockPos(x,y,z);var state=level.getBlockState(at);
+                    if(!state.is(BlockTags.BASE_STONE_OVERWORLD))continue;
+                    var ore=ore(site.seed(),x,y,z,(top-y)/(double)Math.max(1,top-bottom));
+                    if(ore!=null)level.setBlock(at,ore.defaultBlockState(),2);
+                }
+            }
+    }
+    static Block ore(long seed,int x,int y,int z,double depth) {
+        long cell=AerialGeometry24.mix(seed ^ ((long)Math.floorDiv(x,4)<<42)
+            ^ ((long)Math.floorDiv(z,4)<<21) ^ Math.floorDiv(y,3));
+        int roll=(int)Math.floorMod(cell,100);
+        if(roll>=37)return null;
+        if(depth<.27)return roll<15?Blocks.COAL_ORE:roll<27?Blocks.COPPER_ORE:Blocks.IRON_ORE;
+        if(depth<.60)return roll<13?Blocks.IRON_ORE:roll<21?Blocks.GOLD_ORE:roll<29?Blocks.LAPIS_ORE:Blocks.COAL_ORE;
+        return roll<10?Blocks.IRON_ORE:roll<19?Blocks.REDSTONE_ORE:roll<27?Blocks.GOLD_ORE:roll<34?Blocks.DIAMOND_ORE:Blocks.EMERALD_ORE;
+    }
+}

mods/sanctuary/src/main/java/fr/koka/sanctuary/worldgen/drained307/DryOcean307.java

@@ -0,0 +1,71 @@
+package fr.koka.sanctuary.worldgen.drained307;
+
+import fr.koka.sanctuary.SanctuaryMod;
+import fr.koka.sanctuary.worldgen.SanctuaryChunkGenerator;
+import java.util.*;
+import net.minecraft.core.*;
+import net.minecraft.core.registries.*;
+import net.minecraft.resources.ResourceKey;
+import net.minecraft.server.level.ServerLevel;
+import net.minecraft.world.level.*;
+import net.minecraft.world.level.block.Rotation;
+import net.minecraft.world.level.levelgen.structure.*;
+import net.minecraft.world.level.levelgen.structure.pieces.*;
+
+/** Sparse dry remnants on existing lower cave floors; no new cavern or ocean density. */
+public final class DryOcean307 {
+    public static final ResourceKey<Structure> KEY=ResourceKey.create(Registries.STRUCTURE,SanctuaryMod.id("drained_ocean_ruin"));
+    public static final StructureType<DryOceanStructure307> TYPE=Registry.register(BuiltInRegistries.STRUCTURE_TYPE,
+        SanctuaryMod.id("drained_ocean_v307"),()->DryOceanStructure307.CODEC);
+    public static final StructurePieceType PIECE=Registry.register(BuiltInRegistries.STRUCTURE_PIECE,
+        SanctuaryMod.id("drained_ocean_piece_v307"),DryOceanPiece307::new);
+    private static final ThreadLocal<BoundingBox> PLACING=new ThreadLocal<>();
+    private DryOcean307(){}
+    public static void register(){}
+    public static boolean isPlacing(){return PLACING.get()!=null;}
+    public static boolean mayWrite(BlockPos pos){return PLACING.get()!=null&&PLACING.get().isInside(pos);}
+    static void placing(BoundingBox box,Runnable action){var old=PLACING.get();PLACING.set(box);try{action.run();}finally{if(old==null)PLACING.remove();else PLACING.set(old);}}
+    public static List<StructureStart> plan(ServerLevel level,SanctuaryChunkGenerator host) {
+        var result=new ArrayList<StructureStart>();var columns=new HashMap<Long,NoiseColumn>();var reasons=new TreeMap<String,Integer>();
+        var random=new Random(level.getSeed() ^ 0x3070CEA1L);
+        java.util.function.BiFunction<Integer,Integer,NoiseColumn> column=(x,z)->{
+            long key=BlockPos.asLong(x,0,z);var c=columns.get(key);
+            if(c==null){if(columns.size()>=8000)throw new Budget();c=host.aerialBaseColumn24(x,z);columns.put(key,c);}return c;
+        };
+        int target=host.initialDiameter()==1024?4:3;
+        try {
+            outer:for(int attempt=0;attempt<512 && result.size()<target;attempt++) {
+                double a=random.nextDouble()*Math.PI*2,r=host.initialDiameter()*(.10+random.nextDouble()*.27);
+                int x=(int)(Math.cos(a)*r),z=(int)(Math.sin(a)*r);
+                if(result.stream().anyMatch(s->Math.hypot(s.getBoundingBox().getCenter().getX()-x,s.getBoundingBox().getCenter().getZ()-z)<48))continue;
+                var center=column.apply(x,z);
+                for(int floor=60;floor<=174;floor++) {
+                    if(!center.getBlock(floor-1).isSolid()||!center.getBlock(floor).isAir()||!center.getBlock(floor+6).isAir())continue;
+                    String template="underwater_ruin/warm_"+new int[]{2,3,4,5,8}[random.nextInt(5)];
+                    var piece=new DryOceanPiece307(level.getStructureTemplateManager(),template,new BlockPos(x,floor,z),
+                        Rotation.values()[random.nextInt(4)],random.nextLong());
+                    var box=piece.getBoundingBox();
+                    if(host.intersectsExperimentalStructures(box.minX()-1,box.minY()-2,box.minZ()-1,box.maxX()+1,box.maxY()+2,box.maxZ()+1)) {
+                        reasons.merge("reserved",1,Integer::sum);continue;
+                    }
+                    int support=0,total=0;boolean fits=true;
+                    for(int px=box.minX();fits&&px<=box.maxX();px++)for(int pz=box.minZ();fits&&pz<=box.maxZ();pz++) {
+                        var c=column.apply(px,pz);total++;
+                        if(c.getBlock(floor-1).isSolid()&&c.getBlock(floor-2).isSolid())support++;
+                        for(int py=floor;py<=box.maxY()+1;py++)
+                            if(!c.getBlock(py).isAir()||host.protectsDecoration(new BlockPos(px,py,pz))) {fits=false;break;}
+                    }
+                    if(!fits||support*100<total*90){reasons.merge("cave-floor-or-clearance",1,Integer::sum);continue;}
+                    var cp=new ChunkPos(x>>4,z>>4);
+                    if(result.stream().anyMatch(s->s.getChunkPos().equals(cp)))continue;
+                    result.add(new StructureStart(level.registryAccess().lookupOrThrow(Registries.STRUCTURE).getOrThrow(KEY).value(),
+                        cp,0,new PiecesContainer(List.of(piece))));
+                    continue outer;
+                }
+            }
+        }catch(Budget exhausted){reasons.merge("column-budget",1,Integer::sum);}
+        SanctuaryMod.LOGGER.info("Drained307 seed {}: {} / {} dry ruins, {} columns; {}",level.getSeed(),result.size(),target,columns.size(),reasons);
+        return List.copyOf(result);
+    }
+    private static final class Budget extends RuntimeException {}
+}

mods/sanctuary/src/main/java/fr/koka/sanctuary/worldgen/drained307/DryOceanPiece307.java

@@ -0,0 +1,102 @@
+package fr.koka.sanctuary.worldgen.drained307;
+
+import java.nio.charset.StandardCharsets;
+import java.util.*;
+import net.minecraft.core.BlockPos;
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.resources.Identifier;
+import net.minecraft.util.RandomSource;
+import net.minecraft.util.valueproviders.ConstantInt;
+import net.minecraft.world.entity.EntitySpawnReason;
+import net.minecraft.world.entity.EntityTypes;
+import net.minecraft.world.level.*;
+import net.minecraft.world.level.block.*;
+import net.minecraft.world.level.block.entity.ChestBlockEntity;
+import net.minecraft.world.level.block.state.properties.BlockStateProperties;
+import net.minecraft.world.level.chunk.ChunkGenerator;
+import net.minecraft.world.level.levelgen.structure.*;
+import net.minecraft.world.level.levelgen.structure.pieces.StructurePieceSerializationContext;
+import net.minecraft.world.level.levelgen.structure.templatesystem.*;
+import net.minecraft.world.level.levelgen.structure.templatesystem.rule.blockentity.AppendLoot;
+import net.minecraft.world.level.storage.loot.BuiltInLootTables;
+
+/** Native ocean-ruin templates at a certified cave floor, with dry markers and native loot. */
+public final class DryOceanPiece307 extends TemplateStructurePiece {
+    private final long seed;
+    private final Set<Long> occupants=new HashSet<>();
+    public DryOceanPiece307(StructureTemplateManager manager,String template,BlockPos at,Rotation rotation,long seed) {
+        super(DryOcean307.PIECE,0,manager,Identifier.withDefaultNamespace(template),template,settings(rotation),at);
+        this.seed=seed;
+    }
+    public DryOceanPiece307(StructurePieceSerializationContext context,CompoundTag tag) {
+        super(DryOcean307.PIECE,tag,context.structureTemplateManager(),ignored->settings(tag.read("Rot",Rotation.LEGACY_CODEC).orElseThrow()));
+        seed=tag.getLong("Seed").orElseThrow();
+        for(long pos:tag.getLongArray("Occupants").orElseThrow())occupants.add(pos);
+        if(!templateName.matches("underwater_ruin/warm_[1-8]") || occupants.size()>16)
+            throw new IllegalArgumentException("Invalid drained ruin");
+    }
+    private static StructurePlaceSettings settings(Rotation rotation) {
+        // Same warm-ruin archaeology recipe: up to five native suspicious sand blocks.
+        var archaeology=new CappedProcessor(new RuleProcessor(List.of(new ProcessorRule(
+            new BlockMatchTest(Blocks.SAND),AlwaysTrueTest.INSTANCE,PosAlwaysTrueTest.INSTANCE,
+            Blocks.SUSPICIOUS_SAND.defaultBlockState(),new AppendLoot(BuiltInLootTables.OCEAN_RUIN_WARM_ARCHAEOLOGY)))),ConstantInt.of(5));
+        return new StructurePlaceSettings().setRotation(rotation).addProcessor(new BlockRotProcessor(.8F))
+            .addProcessor(BlockIgnoreProcessor.STRUCTURE_AND_AIR).addProcessor(archaeology);
+    }
+    @Override protected void addAdditionalSaveData(StructurePieceSerializationContext context,CompoundTag tag) {
+        super.addAdditionalSaveData(context,tag);tag.store("Rot",Rotation.LEGACY_CODEC,placeSettings.getRotation());
+        tag.putLong("Seed",seed);tag.putLongArray("Occupants",occupants.stream().sorted().mapToLong(Long::longValue).toArray());
+    }
+    @Override protected synchronized void handleDataMarker(String marker,BlockPos pos,ServerLevelAccessor level,RandomSource random,BoundingBox clip) {
+        if(!clip.isInside(pos))return;
+        if(marker.equals("chest")) {
+            if(level.getBlockState(pos).is(Blocks.CHEST))return;
+            level.setBlock(pos,Blocks.CHEST.defaultBlockState(),2);
+            if(level.getBlockEntity(pos) instanceof ChestBlockEntity chest)
+                chest.setLootTable(BuiltInLootTables.UNDERWATER_RUIN_SMALL,seed ^ pos.asLong());
+        } else if(marker.equals("drowned")) {
+            level.setBlock(pos,Blocks.AIR.defaultBlockState(),2);
+            if(!occupants.add(pos.asLong()))return;
+            var zombie=EntityTypes.ZOMBIE.create(level.getLevel(),EntitySpawnReason.STRUCTURE);
+            if(zombie==null)throw new IllegalStateException("Missing ruin zombie");
+            zombie.snapTo(pos,0,0);zombie.finalizeSpawn(level,level.getCurrentDifficultyAt(pos),EntitySpawnReason.STRUCTURE,null);
+            zombie.setPersistenceRequired();zombie.setUUID(UUID.nameUUIDFromBytes(("sanctuary:drained307:"+seed+":"+pos.asLong()).getBytes(StandardCharsets.UTF_8)));
+            level.addFreshEntityWithPassengers(zombie);
+        }
+    }
+    @Override public synchronized void postProcess(WorldGenLevel level,StructureManager manager,ChunkGenerator generator,
+            RandomSource random,BoundingBox clip,ChunkPos chunk,BlockPos pivot) {
+        DryOcean307.placing(getBoundingBox(),()->{
+            super.postProcess(level,manager,generator,RandomSource.create(seed ^ chunk.pack()),clip,chunk,pivot);
+            var box=getBoundingBox();
+            for(int x=Math.max(box.minX(),clip.minX());x<=Math.min(box.maxX(),clip.maxX());x++)
+                for(int z=Math.max(box.minZ(),clip.minZ());z<=Math.min(box.maxZ(),clip.maxZ());z++) {
+                    for(int y=box.minY();y<=box.maxY();y++) {
+                        var pos=new BlockPos(x,y,z);var state=level.getBlockState(pos);
+                        if(state.is(Blocks.WATER))level.setBlock(pos,Blocks.AIR.defaultBlockState(),2);
+                        else if(state.hasProperty(BlockStateProperties.WATERLOGGED)&&state.getValue(BlockStateProperties.WATERLOGGED))
+                            level.setBlock(pos,state.setValue(BlockStateProperties.WATERLOGGED,false),2);
+                    }
+                    long roll=mix(seed ^ BlockPos.asLong(x,0,z));
+                    if(Math.floorMod(roll,7)!=0)continue;
+                    for(int y=box.minY()+1;y<box.maxY();y++) {
+                        var pos=new BlockPos(x,y,z);var below=level.getBlockState(pos.below());
+                        if(level.getBlockState(pos).isAir() && below.isFaceSturdy(level,pos.below(),net.minecraft.core.Direction.UP)
+                            && !below.is(Blocks.CHEST)) {
+                            Block coral=switch((int)Math.floorMod(roll>>>8,4)) {
+                                case 0->Blocks.DEAD_BRAIN_CORAL_BLOCK;case 1->Blocks.DEAD_TUBE_CORAL;
+                                case 2->Blocks.DEAD_FIRE_CORAL;default->Blocks.DEAD_BUBBLE_CORAL;
+                            };
+                            var dry=coral.defaultBlockState();
+                            // Coral plants default to waterlogged even when already dead.
+                            // A broken support would otherwise release a new water source here.
+                            if(dry.hasProperty(BlockStateProperties.WATERLOGGED)) dry=dry.setValue(BlockStateProperties.WATERLOGGED,false);
+                            if(dry.canSurvive(level,pos))level.setBlock(pos,dry,2);
+                            break;
+                        }
+                    }
+                }
+        });
+    }
+    private static long mix(long n){n=(n^n>>>30)*0xbf58476d1ce4e5b9L;n=(n^n>>>27)*0x94d049bb133111ebL;return n^n>>>31;}
+}

mods/sanctuary/src/main/java/fr/koka/sanctuary/worldgen/drained307/DryOceanStructure307.java

@@ -0,0 +1,11 @@
+package fr.koka.sanctuary.worldgen.drained307;
+import com.mojang.serialization.MapCodec;
+import java.util.Optional;
+import net.minecraft.world.level.levelgen.structure.Structure;
+import net.minecraft.world.level.levelgen.structure.StructureType;
+public final class DryOceanStructure307 extends Structure {
+    public static final MapCodec<DryOceanStructure307> CODEC=simpleCodec(DryOceanStructure307::new);
+    public DryOceanStructure307(StructureSettings settings){super(settings);}
+    @Override protected Optional<GenerationStub> findGenerationPoint(GenerationContext context){return Optional.empty();}
+    @Override public StructureType<?> type(){return DryOcean307.TYPE;}
+}

mods/sanctuary/src/main/java/fr/koka/sanctuary/worldgen/heritage/HeritagePlanner23.java

@@ -240,13 +240,14 @@ public final class HeritagePlanner23 {
                 for(int step=0;step<target/8;step++) {
                     RouteDraft chosen=null; List<XZ> chosenPath=null; int chosenFace=face;
                     var last=path.getLast();
-                    for(int turn:new int[]{0,1,-1}) {
+                    for(int turn:new int[]{0}) {
                         int direction=(face+turn+4)&3;
-                        // Give long straight runs priority, with curves only where the grade needs them.
+                        // A branch stays on its initial axis. An obstruction ends it instead of curling back.
                         var end=last.move(direction,8);int top=p.surface(end.x(),end.z());
                         if(top<14||top>350)continue;
                         if(path.stream().anyMatch(at->Math.abs(at.x()-end.x())+Math.abs(at.z()-end.z())<5))continue;
-                        if(cells.containsKey(key(end.x(),end.z())))continue;
+                        // Keep a real separation from existing parallel routes, outside the shared junction.
+                        if(proposedNearRoute307(path.getFirst(), end, cells)) continue;
                         var proposed=new ArrayList<>(path);line(proposed,end);
                         var endEntry=new Entry(end.x(),top+1,end.z(),(direction+2)&3);
                         var historical=landmarks.stream().filter(l->!l.id().startsWith("natural_rail_")&&!l.id().startsWith("rail_branch_")).toList();
@@ -260,7 +261,7 @@ public final class HeritagePlanner23 {
                 var end=best.path().getLast();
                 var terminal=new Landmark(id,LandmarkKind.MINE,new Entry(end.x(),end.floorY()+1,end.z(),face));
                 landmarks.add(terminal);
-                if(best.path().size() >= 49 && landmarks.size() < 15 && links.size() < 19) {
+                if(arm.depth()==0 && best.path().size() >= 65 && landmarks.size() < 15 && links.size() < 19) {
                     int middle=best.path().size()/2;var at=best.path().get(middle);var after=best.path().get(middle+1);
                     int tangent=direction(at.x(),at.z(),after.x(),after.z());
                     var fork=new Landmark(id+"_fork",LandmarkKind.MINE,new Entry(at.x(),at.floorY()+1,at.z(),tangent));
@@ -279,11 +280,18 @@ public final class HeritagePlanner23 {
                 }
                 serial++;
                 // Forward continuation and a lateral branch share their ballast; the switch is repairable.
-                if(arm.depth()<2){queue.addFirst(new Arm(terminal,(face+(serial%2==0?1:3))&3,arm.depth()+1));queue.addLast(new Arm(terminal,face,arm.depth()+1));}
+                if(arm.depth()==0) queue.addLast(new Arm(terminal,face,1));
             }
         } catch(BudgetExceeded exhausted){p.reject("branched-rail-budget");}
     }
 
+    private static boolean proposedNearRoute307(XZ start, XZ end, Map<Long, OwnedCell> cells) {
+        if(Math.abs(start.x()-end.x())+Math.abs(start.z()-end.z()) <= 16) return false;
+        for(int dx=-10;dx<=10;dx++) for(int dz=-10;dz<=10;dz++)
+            if(cells.containsKey(key(end.x()+dx,end.z()+dz))) return true;
+        return false;
+    }
+
     private static List<Candidate> candidates(long seed, Kind kind, int cx, int cz, int diameter,
             List<Site> sites, List<Landmark> landmarks, Probe probe) {
         double angle = unit(mix(seed ^ 0x19ACEL)) * Math.PI * 2 + kind.ordinal() * 2.399963229728653;

mods/sanctuary/src/main/java/fr/koka/sanctuary/worldgen/transit/TransitPlan21.java

@@ -64,8 +64,8 @@ public record TransitPlan21(List<Module> modules, int samples, String diagnostic
         modules = List.copyOf(modules);
         if (modules.size() > 64 || samples < 0 || samples > MAX_SAMPLES || diagnostic == null || diagnostic.length() > 1024)
             throw new IllegalArgumentException("Invalid transit planning result");
-        if (!modules.isEmpty() && modules.stream().filter(m -> m.kind() == Kind.ACCESS).count() != 2)
-            throw new IllegalArgumentException("A through-gallery needs two surface accesses");
+        if (!modules.isEmpty() && !List.of(2L,4L).contains(modules.stream().filter(m -> m.kind() == Kind.ACCESS).count()))
+            throw new IllegalArgumentException("Each through-gallery needs two surface accesses");
         for (int i = 0; i < modules.size(); i++) for (int j = i + 1; j < modules.size(); j++) {
             var a = modules.get(i); var b = modules.get(j);
             if (a.minX() <= b.maxX() && a.maxX() >= b.minX() && a.minZ() <= b.maxZ() && a.maxZ() >= b.minZ())

mods/sanctuary/src/main/java/fr/koka/sanctuary/worldgen/transit/TransitPlanner29.java

@@ -12,6 +12,27 @@ public final class TransitPlanner29 {
     public static final int MAX_COLUMNS = 12_000;
     private TransitPlanner29() {}
 
+    public static TransitPlan21 plan307(long seed, int cx, int cz, int diameter, Terrain terrain) {
+        var first=plan(seed,cx,cz,diameter,terrain);
+        if(first.isEmpty()) return first;
+        Terrain remaining=new Terrain() {
+            @Override public boolean owns(int x,int z) {return terrain.owns(x,z);}
+            @Override public boolean solid(int x,int y,int z) {return terrain.solid(x,y,z);}
+            @Override public int surfaceY(int x,int z) {return terrain.surfaceY(x,z);}
+            @Override public boolean protectedAt(int x,int y,int z) {
+                // Separate corridors and their entrances, with untouched rock between them.
+                for(var m:first.modules()) if(x>=m.minX()-24&&x<=m.maxX()+24&&z>=m.minZ()-24&&z<=m.maxZ()+24) return true;
+                return terrain.protectedAt(x,y,z);
+            }
+        };
+        var second=plan(seed ^ 0x3077A115L,cx,cz,diameter,remaining);
+        if(second.isEmpty() || first.modules().size()+second.modules().size()>64
+            || first.samples()+second.samples()>TransitPlan21.MAX_SAMPLES)
+            return new TransitPlan21(first.modules(),first.samples(),first.diagnostic()+"; second-refused="+second.diagnostic());
+        var modules=new ArrayList<>(first.modules());modules.addAll(second.modules());
+        return new TransitPlan21(modules,first.samples()+second.samples(),"two-traversals; "+first.diagnostic()+"; "+second.diagnostic());
+    }
+
     public static TransitPlan21 plan(long seed, int cx, int cz, int diameter, Terrain terrain) {
         if (!List.of(512, 724, 1024).contains(diameter)) throw new IllegalArgumentException("Unsupported transit diameter");
         var p = new Probe(terrain); int layouts = 0; String reason = "no natural entrance pair";

mods/sanctuary/src/main/resources/assets/sanctuary/lang/en_us.json

@@ -238,5 +238,6 @@
   "sanctuary.structures.census.aerial.status.unknown": "unknown",
   "structure.sanctuary.aerial_merchant_ship": "Merchant ship",
   "structure.sanctuary.aerial_mineral_islet": "Mineral islet",
-  "biome.sanctuary.swamp27_caves": "Underground swamp"
+  "biome.sanctuary.swamp27_caves": "Underground swamp",
+  "structure.sanctuary.drained_ocean_ruin": "Drained Ocean Ruins"
 }

mods/sanctuary/src/main/resources/assets/sanctuary/lang/fr_fr.json

@@ -238,5 +238,6 @@
   "sanctuary.structures.census.aerial.status.unknown": "inconnu",
   "structure.sanctuary.aerial_merchant_ship": "Bateau marchand",
   "structure.sanctuary.aerial_mineral_islet": "Îlot minéral",
-  "biome.sanctuary.swamp27_caves": "Marais souterrain"
+  "biome.sanctuary.swamp27_caves": "Marais souterrain",
+  "structure.sanctuary.drained_ocean_ruin": "Ruines océaniques asséchées"
 }

mods/sanctuary/src/main/resources/data/sanctuary/worldgen/structure/drained_ocean_ruin.json

@@ -0,0 +1,7 @@
+{
+  "type": "sanctuary:drained_ocean_v307",
+  "biomes": "#minecraft:is_overworld",
+  "step": "top_layer_modification",
+  "terrain_adaptation": "none",
+  "spawn_overrides": {}
+}

packwiz/pack.toml

@@ -1,6 +1,6 @@
 name = "Sanctuary"
 author = "KOKA99CAB"
-version = "0.1.0-alpha.30.6"
+version = "0.1.0-alpha.30.7"
 pack-format = "packwiz:1.1.0"
 
 [index]

scripts/archive_terrain_atlas.py

@@ -57,7 +57,7 @@ def main():
         raise SystemExit("Empty atlas or duplicate seed/size")
     for name in ("scripts/terrain_atlas.py", "scripts/terrain-atlas-requirements.txt",
                  "scripts/archive_terrain_atlas.py", "docs/terrain-atlas.md",
-                 "scripts/structure_atlas.py", f"docs/generation-alpha{version.split('alpha.')[-1]}.md", f"docs/testing-alpha{version.split('alpha.')[-1]}.md"):
+                 "scripts/structure_atlas.py", "scripts/finishing_atlas.py", f"docs/generation-alpha{version.split('alpha.')[-1]}.md", f"docs/testing-alpha{version.split('alpha.')[-1]}.md"):
         files[name] = (ROOT / name).read_bytes()
     for path in args.extra:
         key = "structures/" + path.name

scripts/finishing_atlas.py

@@ -0,0 +1,46 @@
+#!/usr/bin/env python3
+"""Archive native 30.7 structure witnesses over the unchanged 30.6 terrain field."""
+import argparse, hashlib, json, re
+from pathlib import Path
+import matplotlib
+matplotlib.use('Agg')
+import matplotlib.pyplot as plt
+from matplotlib.patches import Rectangle
+import numpy as np
+
+p=argparse.ArgumentParser(description=__doc__)
+for name in ('terrain','village','transit','aerial','ruins','output'): p.add_argument('--'+name,type=Path,required=True)
+a=p.parse_args()
+data={name:json.loads(getattr(a,name).read_text()) for name in ('terrain','village','transit','aerial','ruins')}
+t=data['terrain']; seed=str(t['seed']); size=t['diameter']
+for name in ('village','transit','aerial','ruins'):
+ d=data[name]
+ if str(d['seed'])!=seed or d['diameter']!=size or not d.get('passed'): raise ValueError('Unmatched/failed '+name)
+cols=np.asarray(t['variants']['current306']['columns']);xs,zs=np.unique(cols[:,0]),np.unique(cols[:,1]);g=cols.reshape(len(zs),len(xs),5)
+fig,ax=plt.subplots(figsize=(11,10),layout='constrained')
+step=t['map_step'];extent=(xs[0]-step/2,xs[-1]+step/2,zs[-1]+step/2,zs[0]-step/2)
+im=ax.imshow(np.ma.masked_where(g[:,:,2]==0,g[:,:,2]),extent=extent,cmap='terrain',vmin=0,vmax=400,interpolation='nearest')
+for link in data['village']['rail_links']:
+ if link['kind']=='FREIGHT': ax.plot([v['x'] for v in link['points']],[v['z'] for v in link['points']],color='#962427',lw=2)
+walks=data['transit'].get('walk',[])
+if isinstance(walks,dict): walks=[walks]
+for walk in walks:
+ gates=[v['gate'] for v in walk['surface_accesses']]
+ ax.plot([v[0] for v in gates],[v[2] for v in gates],color='#223494',lw=2,ls='--',marker='s',ms=4)
+for b in data['ruins']['bounds']:
+ v={k:int(n) for k,n in re.findall(r'(minX|minZ|maxX|maxZ)=(-?\d+)',b)}
+ ax.add_patch(Rectangle((v['minX'],v['minZ']),v['maxX']-v['minX']+1,v['maxZ']-v['minZ']+1,fill=False,edgecolor='#02abb2',linewidth=2))
+for site in data['aerial']['geometry']:
+ width,depth=(site['width'],site['depth']) if site['facing']%2==0 else (site['depth'],site['width'])
+ colour='#8a4196' if site['kind']=='NATURAL_ISLET' else '#41301f'
+ ax.add_patch(Rectangle((site['minX'],site['minZ']),width,depth,fill=False,edgecolor=colour,linewidth=1.3))
+ ax.scatter([site['minX']+width//2],[site['minZ']+depth//2],color=colour,s=20,marker='x')
+ax.scatter([0],[0],marker='+',s=70,color='black')
+for label,color,style in [('Rails prévus — lacunes réparables','#962427','-'),('Axes des traversées parcourues','#223494','--'),('Ruines asséchées — emprises','#02abb2','-'),('Trésors du terrain aérien — emprises','#8a4196','-'),('Navires restaurés — emprises','#41301f','-')]:ax.plot([],[],color=color,ls=style,label=label)
+ax.legend(loc='upper left',fontsize=8);ax.set(xlabel='X (blocs)',ylabel='Z (blocs) · nord en haut',aspect='equal')
+ax.set_title(f'Sanctuary alpha.30.7 · {size} · graine {seed}\nInstallations sur le relief natif inchangé de 30.6')
+fig.colorbar(im,ax=ax,shrink=.7,label='Altitude du terrain Y')
+fig.supxlabel('Relief échantillonné ; rails planifiés. Traversées, coffres et ruines contrôlés dans les chunks FULL.\nLes rectangles indiquent des réservations, pas la forme construite ni les frontières des biomes.',fontsize=9)
+a.output.mkdir(parents=True,exist_ok=True)
+for ext in ('png','pdf'):fig.savefig(a.output/f'installations-{size}-{seed}.{ext}',dpi=160)
+(a.output/f'installations-{size}-{seed}-provenance.json').write_text(json.dumps({k:{'path':str(getattr(a,k)),'sha256':hashlib.sha256(getattr(a,k).read_bytes()).hexdigest()} for k in data},indent=2)+'\n')