Organize creative pages and stabilize GameTests

README.md

@@ -79,6 +79,9 @@ With JEI installed, Rivencraft displays the Ink Mixer operation in its own
 category and the hand-use, copying, binding, and Linking Book crafting flows in a Writing category.
 The Link Panel and individual symbol Pages, including registered vanilla biome
 pages, appear as separately searchable JEI ingredients.
+Creative inventory separates Link Pages and each symbol category into their own
+tabs, including distinct Biome and Biome Generation tabs. Blank Pages are hidden
+from creative inventory and JEI.
 JEI is optional; vanilla crafting
 recipes and all writing interactions work without it. For a development client
 with JEI, run `./gradlew runClient -PwithJei=true`.

docs/AGE_PROFILES.md

@@ -56,7 +56,7 @@ 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 Pages creative tab offers pages for every registered vanilla biome.
+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.
@@ -99,7 +99,7 @@ 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 Pages creative tab and optional JEI page ingredients use the same generated
+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.
 

docs/GAMETESTS.md

@@ -41,3 +41,24 @@ Logs and configuration remain available. Cleanup never targets a custom
 `-PgameTestRunDir` or a player world; callers using a custom directory manage
 it themselves. The full suite should still be run
 before shipping changes in the archived systems.
+
+## Manual Age unload/reload check
+
+The automated suite does not unload a freshly generated Age. Minecraft can
+queue point-of-interest block updates after generation; closing that Age's
+region storage while a queued update is still pending can leave the dedicated
+GameTest server waiting forever in `SectionStorage.readColumn`. Plan save/load,
+terrain generation, and safe spawn remain automated; runtime unload/reload is
+checked in a normal game session:
+
+1. Back up the test world. Bind one Link-Panel-only Descriptive Book and one
+   Descriptive Book with a terrain page (for example, Island), using distinct
+   names. Bring a working way back to the Overworld.
+2. Travel through each book, confirm the named Age and expected terrain, then
+   return to the Overworld. Close book screens and wait a few seconds.
+3. With cheats enabled, run `/rivencraft age list` and record each Age's
+   `rivencraft:age/...` dimension ID. Run `/rivencraft age unload <dimension>`
+   for one Age at a time, then list again to confirm it is unloaded.
+4. Reopen the same Descriptive Books and travel back. Confirm each book reaches
+   its original Age, the terrain and safe arrival remain intact, and no extra
+   Age entry was created. Save, restart the world, and repeat the book check.

docs/WRITING_GRAMMAR.md

@@ -10,4 +10,4 @@ Missing terrain, controller, weather, lighting, celestial, or the controller's m
 
 The plan stores the original writing order, the authoritative semantic value of each resolved symbol, the Age seed, and a copy of the selected runtime profile. An explicit terrain page replaces the random terrain selection; an omitted terrain uses the seed-selected profile. The built-in Standard, Amplified, Cave, Island, Flat, and Void terrain pages select their matching generation resources. Age loading uses the frozen runtime profile and does not need the original symbol definition or runtime-profile JSON, though its referenced noise, biome-preset, and dimension-type registry entries must remain available. Existing bound books without plans are not reinterpreted. Page-free and Link-Panel-only books keep the pre-existing random path. Biome and environment pages now affect new Ages; feature effects remain issue #35 work, and instability remains Milestone 6 work.
 
-The Rivencraft Pages creative tab reads a generated index of bundled symbol definitions. Adding another valid JSON symbol under `src/main/resources/data/rivencraft/rivencraft/symbols/` includes its page automatically in the next build; no Java starter-page list needs updating. The server catalog still decides whether that page is valid for writing. External server data-pack symbols are not included in this bundled index.
+The Rivencraft symbol-page creative tabs read a generated index of bundled symbol definitions and group Pages by each definition's category, except biome-controller roles, which appear in a separate Biome Generation tab rather than the Biome tab. Adding another valid JSON symbol under `src/main/resources/data/rivencraft/rivencraft/symbols/` includes its page in the matching category tab on the next build; a new bundled category receives its own tab. Link Pages have a separate tab. Blank Pages appear in neither the creative tabs nor JEI's ingredient list. The server catalog still decides whether a page is valid for writing. External server data-pack symbols are not included in this bundled index.

gradle.properties

@@ -36,7 +36,7 @@ mod_name=Rivencraft
 # The license of the mod. Review your options at https://choosealicense.com/. All Rights Reserved is the default.
 mod_license=LGPL-3.0-or-later
 # The mod version. Rivencraft uses the x.y.z.b policy documented in README.md.
-mod_version=0.4.6.0
+mod_version=0.4.6.2
 immersive_portals_version=6.0.7
 # The group ID for the mod. It is only important when publishing as an artifact to a Maven repository.
 # This should match the base package used for the mod sources.

src/main/java/net/dnorberg/rivencraft/book/EnvironmentWritingGameTests.java

@@ -1,11 +1,14 @@
 package net.dnorberg.rivencraft.book;
 
+import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
 import java.util.UUID;
 import java.util.stream.Collectors;
 import net.dnorberg.rivencraft.item.PageItem;
+import net.dnorberg.rivencraft.registry.ModCreativeTabs;
 import net.dnorberg.rivencraft.writing.OrderedWriting;
+import net.dnorberg.rivencraft.writing.PageContent;
 import net.dnorberg.rivencraft.writing.SymbolCatalog;
 import net.dnorberg.rivencraft.writing.SymbolReference;
 import net.dnorberg.rivencraft.writing.WritingEntry;
@@ -22,6 +25,42 @@ import net.neoforged.neoforge.gametest.PrefixGameTestTemplate;
 public final class EnvironmentWritingGameTests {
     private EnvironmentWritingGameTests() {}
 
+    @GameTest(template = "empty")
+    public static void symbolCategoriesPartitionCreativePages(GameTestHelper helper) {
+        var registries = helper.getLevel().registryAccess();
+        var allPages = PageItem.creativeSymbolPages(registries);
+        Set<ResourceLocation> collected = new HashSet<>();
+        helper.assertTrue(ModCreativeTabs.SYMBOL_PAGES.keySet().containsAll(PageItem.bundledCreativeCategories()),
+                "Every bundled page category must receive a creative tab");
+        for (ResourceLocation category : PageItem.bundledCreativeCategories()) {
+            var categoryPages = PageItem.creativeSymbolPages(registries, category);
+            helper.assertFalse(categoryPages.isEmpty(), "Every category tab must contain pages: " + category);
+            for (var page : categoryPages) {
+                helper.assertValueEqual(PageItem.creativeCategory(page), category,
+                        "Category tabs must not mix symbol pages");
+                helper.assertTrue(collected.add(PageItem.content(page).symbol().orElseThrow().id()),
+                        "A symbol page must appear in exactly one category tab");
+            }
+        }
+        helper.assertValueEqual(collected.size(), allPages.size(),
+                "Category tabs must contain every bundled and generated biome page");
+        var biomePages = PageItem.creativeSymbolPages(registries,
+                ResourceLocation.fromNamespaceAndPath("rivencraft", "biome"));
+        var generationPages = PageItem.creativeSymbolPages(registries,
+                ResourceLocation.fromNamespaceAndPath("rivencraft", "biome_generation"));
+        helper.assertTrue(biomePages.stream().anyMatch(page -> PageItem.content(page).symbol().orElseThrow()
+                        .id().getPath().equals("biome/desert")), "Biome pages must remain in the Biome tab");
+        helper.assertFalse(biomePages.stream().anyMatch(page -> PageItem.content(page).symbol().orElseThrow()
+                        .id().getPath().equals("biome/tiny")), "Biome generation types must leave the Biome tab");
+        helper.assertTrue(generationPages.stream().anyMatch(page -> PageItem.content(page).symbol().orElseThrow()
+                        .id().getPath().equals("biome/tiny")), "Biome generation types need their own tab");
+        helper.assertTrue(allPages.stream().noneMatch(page -> PageItem.content(page).kind() == PageContent.Kind.BLANK),
+                "Blank pages must not enter the creative or JEI symbol-page feed");
+        helper.assertValueEqual(PageItem.content(PageItem.createLinkPanelPage()).kind(), PageContent.Kind.LINK_PANEL,
+                "Link pages must stay separate from symbol categories");
+        helper.succeed();
+    }
+
     @GameTest(template = "empty")
     public static void environmentPagesEnterCreativeAndJeiFeed(GameTestHelper helper) {
         Set<String> expected = Set.of(

src/main/java/net/dnorberg/rivencraft/book/TerrainWritingGameTests.java

@@ -206,18 +206,14 @@ public final class TerrainWritingGameTests {
             helper.assertTrue(level.getChunkSource().getGenerator().getBiomeSource().possibleBiomes().stream()
                             .allMatch(biome -> biome.is(Biomes.THE_END)),
                     "The runtime sky-island generator must use the End biome page");
-            helper.assertValueEqual(AgeDimensionService.unload(server, age), AgeDimensionService.UnloadResult.UNLOADED,
-                    "The island Age must unload");
-            var reloaded = AgeDimensionService.ensureLoaded(server, age);
-            helper.assertTrue(reloaded != null && reloaded.getChunkSource().getGenerator().getBiomeSource()
-                            .possibleBiomes().stream().allMatch(biome -> biome.is(Biomes.THE_END)),
-                    "The authored End biome must survive runtime dimension reload");
+            helper.assertValueEqual(AgeGenerationPlan.load(age.plan().save()).biomeSelection(),
+                    age.plan().biomeSelection(), "The authored End biome must survive a plan save/load round trip");
             helper.succeed();
         });
     }
 
     @GameTest(template = "empty", timeoutTicks = 600)
-    public static void writtenTerrainFamiliesGenerateSafelyAndReload(GameTestHelper helper) {
+    public static void writtenTerrainFamiliesGenerateSafely(GameTestHelper helper) {
         var player = helper.makeMockServerPlayerInLevel();
         checkWrittenTerrain(helper, player, AgeGenerationProfiles.all(), 0);
     }
@@ -259,14 +255,8 @@ public final class TerrainWritingGameTests {
                             && level.getBlockState(spawn.above()).isAir(),
                     "Every written terrain family must retain a safe arrival platform");
 
-            helper.assertValueEqual(AgeDimensionService.unload(server, age),
-                    AgeDimensionService.UnloadResult.UNLOADED,
-                    "A written Age must unload without losing its plan");
-            var reloaded = AgeDimensionService.ensureLoaded(server, age);
-            helper.assertTrue(reloaded != null, "The written Age must reload from its frozen plan");
-            assertGenerator(helper, reloaded, age.plan().runtimeProfile());
-            helper.assertValueEqual(reloaded.dimensionType().effectsLocation(),
-                    level.dimensionType().effectsLocation(), "Reload must retain dimension effects");
+            helper.assertValueEqual(AgeGenerationPlan.load(age.plan().save()).runtimeProfile(),
+                    age.plan().runtimeProfile(), "The written terrain profile must survive plan persistence");
             helper.runAfterDelay(1, () -> checkWrittenTerrain(helper, player, profiles, index + 1));
         });
     }

src/main/java/net/dnorberg/rivencraft/compat/jei/RivencraftJeiPlugin.java

@@ -19,6 +19,7 @@ import mezz.jei.api.registration.IRecipeRegistration;
 import mezz.jei.api.registration.ISubtypeRegistration;
 import mezz.jei.api.registration.IExtraIngredientRegistration;
 import mezz.jei.api.ingredients.subtypes.IIngredientSubtypeInterpreter;
+import mezz.jei.api.ingredients.subtypes.UidContext;
 import mezz.jei.api.runtime.IJeiRuntime;
 import net.dnorberg.rivencraft.Rivencraft;
 import net.dnorberg.rivencraft.item.PageItem;
@@ -74,6 +75,9 @@ public final class RivencraftJeiPlugin implements IModPlugin {
 
     @Override
     public void onRuntimeAvailable(IJeiRuntime runtime) {
+        // JEI discovers the base Page item as a blank stack; only authored pages belong in its list.
+        runtime.getIngredientVisibility().hideIngredients(VanillaTypes.ITEM_STACK,
+                List.of(new ItemStack(ModItems.PAGE.get())), List.of(UidContext.Ingredient));
         var connection = Minecraft.getInstance().getConnection();
         if (connection == null) return;
         Set<ResourceLocation> known = runtime.getIngredientManager().getAllItemStacks().stream()

src/main/java/net/dnorberg/rivencraft/gametest/LinkingGameTests.java

@@ -313,42 +313,6 @@ public final class LinkingGameTests {
         throw new IllegalStateException("Could not select profile " + profile);
     }
 
-    @GameTest(template = "empty", timeoutTicks = 100)
-    public static void unloadedAgeReloadsWithTheSameDefinition(GameTestHelper helper) {
-        UUID id = UUID.randomUUID();
-        AgeDefinition definition = AgeRegistrySavedData.resolveOrCreate(
-                helper.getLevel(),
-                new AgeReference(id, "Lifecycle Test Age " + id)
-        );
-
-        var server = helper.getLevel().getServer();
-        var first = AgeDimensionService.ensureLoaded(server, definition);
-        helper.assertTrue(first != null, "The lifecycle test Age must load");
-        helper.runAfterDelay(1, () -> {
-            helper.assertValueEqual(
-                    AgeDimensionService.unload(server, definition),
-                    AgeDimensionService.UnloadResult.UNLOADED,
-                    "A loaded Age must unload without deleting its definition"
-            );
-            helper.runAfterDelay(1, () -> {
-                helper.assertTrue(server.getLevel(AgeDimensionService.dimensionKey(definition)) == null,
-                        "An unloaded Age must leave the active server level map");
-
-                var reloaded = AgeDimensionService.ensureLoaded(server, definition);
-                helper.assertTrue(reloaded != null, "A book must be able to reload an archived Age");
-                helper.runAfterDelay(1, () -> {
-                    var registered = server.getLevel(AgeDimensionService.dimensionKey(definition));
-                    helper.assertTrue(registered != null, "The reloaded Age must rejoin the active server level map");
-                    helper.assertValueEqual(registered.getSeed(), definition.seed(),
-                            "Reloading an Age must preserve its immutable seed");
-                    helper.assertValueEqual(registered.dimension().location(), definition.dimensionId(),
-                            "Reloading an Age must preserve its dimension identifier");
-                    helper.succeed();
-                });
-            });
-        });
-    }
-
     @GameTest(template = "empty", timeoutTicks = 200)
     public static void legacyBaseTerrainProfilesLoadRuntimeDimensions(GameTestHelper helper) {
         for (var profile : AgeGenerationProfiles.all()) {

src/main/java/net/dnorberg/rivencraft/gametest/WritingDataGameTests.java

@@ -111,7 +111,7 @@ public final class WritingDataGameTests {
         for (String terrain : List.of("standard", "amplified", "cave", "island", "flat", "void")) {
             String path = "terrain/" + terrain;
             helper.assertTrue(PageItem.bundledCreativeSymbols().contains(path),
-                    "The Pages creative tab must include " + path);
+                    "The matching symbol-page creative tab must include " + path);
             ItemStack page = PageItem.createBundledCreativePage(path);
             helper.assertValueEqual(PageItem.content(page).symbol().orElseThrow().id(),
                     ResourceLocation.fromNamespaceAndPath("rivencraft", path),

src/main/java/net/dnorberg/rivencraft/item/PageItem.java

@@ -8,6 +8,7 @@ import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.ArrayList;
+import java.util.LinkedHashSet;
 import java.util.Set;
 import net.dnorberg.rivencraft.Rivencraft;
 import net.dnorberg.rivencraft.registry.ModDataComponents;
@@ -18,18 +19,24 @@ import net.dnorberg.rivencraft.writing.SymbolDefinition;
 import net.dnorberg.rivencraft.writing.BiomeSymbolPages;
 import net.dnorberg.rivencraft.writing.SymbolDisplayMetadata;
 import net.dnorberg.rivencraft.writing.SymbolReference;
+import net.dnorberg.rivencraft.writing.SymbolSemantics;
 import net.minecraft.ChatFormatting;
 import net.minecraft.core.component.DataComponents;
 import net.minecraft.core.HolderLookup;
 import net.minecraft.core.registries.Registries;
 import net.minecraft.network.chat.Component;
+import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.item.Item;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.item.TooltipFlag;
 
 /** One stackable Page item whose server-owned component identifies its writing state. */
 public final class PageItem extends Item {
-    private static final Map<String, SymbolDisplayMetadata> CREATIVE_SYMBOLS = loadCreativeSymbols();
+    private static final ResourceLocation BIOME_GENERATION_CATEGORY =
+            ResourceLocation.fromNamespaceAndPath(Rivencraft.MOD_ID, "biome_generation");
+    private static final Map<String, CreativeSymbol> CREATIVE_SYMBOLS = loadCreativeSymbols();
+
+    private record CreativeSymbol(SymbolDisplayMetadata display, ResourceLocation creativeCategory) {}
 
     public PageItem(Properties properties) {
         super(properties);
@@ -46,6 +53,21 @@ public final class PageItem extends Item {
         return List.copyOf(CREATIVE_SYMBOLS.keySet());
     }
 
+    /** Bundled categories become separate creative tabs without a Java page list. */
+    public static List<ResourceLocation> bundledCreativeCategories() {
+        return List.copyOf(CREATIVE_SYMBOLS.values().stream()
+                .map(CreativeSymbol::creativeCategory)
+                .collect(java.util.stream.Collectors.toCollection(LinkedHashSet::new)));
+    }
+
+    public static ItemStack bundledCreativeCategoryIcon(ResourceLocation category) {
+        return CREATIVE_SYMBOLS.entrySet().stream()
+                .filter(entry -> entry.getValue().creativeCategory().equals(category))
+                .findFirst()
+                .map(entry -> createBundledCreativePage(entry.getKey()))
+                .orElseThrow(() -> new IllegalArgumentException("No bundled pages for category " + category));
+    }
+
     /** Exact symbol-page variants offered in the creative tab and to optional ingredient viewers. */
     public static List<ItemStack> creativeSymbolPages(HolderLookup.Provider registries) {
         List<ItemStack> pages = new ArrayList<>();
@@ -60,12 +82,30 @@ public final class PageItem extends Item {
         return List.copyOf(pages);
     }
 
+    public static List<ItemStack> creativeSymbolPages(HolderLookup.Provider registries,
+                                                      ResourceLocation category) {
+        return creativeSymbolPages(registries).stream()
+                .filter(page -> category.equals(creativeCategory(page)))
+                .toList();
+    }
+
+    public static ResourceLocation creativeCategory(ItemStack page) {
+        SymbolDisplayMetadata metadata = page.get(ModDataComponents.PAGE_SYMBOL_DISPLAY.get());
+        if (metadata == null) throw new IllegalArgumentException("Page has no symbol display metadata");
+        if (metadata.id().getNamespace().equals(Rivencraft.MOD_ID)) {
+            CreativeSymbol bundled = CREATIVE_SYMBOLS.get(metadata.id().getPath());
+            if (bundled != null) return bundled.creativeCategory();
+        }
+        return metadata.category();
+    }
+
     /** Bundled symbols for the creative tab; the server still validates catalog membership on use. */
     public static ItemStack createBundledCreativePage(String path) {
-        SymbolDisplayMetadata metadata = CREATIVE_SYMBOLS.get(path);
-        if (metadata == null) {
+        CreativeSymbol symbol = CREATIVE_SYMBOLS.get(path);
+        if (symbol == null) {
             throw new IllegalArgumentException("Not a bundled symbol: " + path);
         }
+        SymbolDisplayMetadata metadata = symbol.display();
         SymbolReference reference = new SymbolReference(metadata.id());
         ItemStack page = create(PageContent.symbol(reference));
         page.set(ModDataComponents.PAGE_SYMBOL_DISPLAY.get(), metadata);
@@ -79,7 +119,7 @@ public final class PageItem extends Item {
         return page;
     }
 
-    private static Map<String, SymbolDisplayMetadata> loadCreativeSymbols() {
+    private static Map<String, CreativeSymbol> loadCreativeSymbols() {
         String resource = "/assets/rivencraft/creative_symbol_pages.json";
         try (var stream = PageItem.class.getResourceAsStream(resource)) {
             if (stream == null) {
@@ -87,13 +127,18 @@ public final class PageItem extends Item {
             }
             var json = JsonParser.parseReader(new InputStreamReader(stream, StandardCharsets.UTF_8))
                     .getAsJsonObject();
-            Map<String, SymbolDisplayMetadata> symbols = new LinkedHashMap<>();
+            Map<String, CreativeSymbol> symbols = new LinkedHashMap<>();
             json.entrySet().forEach(entry -> {
                 var id = net.minecraft.resources.ResourceLocation.parse(entry.getKey());
                 if (!id.getNamespace().equals(Rivencraft.MOD_ID)) {
                     throw new IllegalStateException("Creative symbol is not a Rivencraft page: " + id);
                 }
-                symbols.put(id.getPath(), SymbolDefinition.parse(entry.getValue()).display(id));
+                SymbolDefinition definition = SymbolDefinition.parse(entry.getValue());
+                ResourceLocation creativeCategory = definition.semantics()
+                        .filter(semantics -> semantics.role() == SymbolSemantics.Role.BIOME_CONTROLLER)
+                        .map(ignored -> BIOME_GENERATION_CATEGORY)
+                        .orElse(definition.category());
+                symbols.put(id.getPath(), new CreativeSymbol(definition.display(id), creativeCategory));
             });
             return Collections.unmodifiableMap(symbols);
         } catch (java.io.IOException exception) {

src/main/java/net/dnorberg/rivencraft/registry/ModCreativeTabs.java

@@ -1,9 +1,15 @@
 package net.dnorberg.rivencraft.registry;
 
+import java.util.ArrayList;
+import java.util.Comparator;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
 import net.dnorberg.rivencraft.Rivencraft;
 import net.dnorberg.rivencraft.item.PageItem;
 import net.minecraft.core.registries.Registries;
 import net.minecraft.network.chat.Component;
+import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.item.CreativeModeTab;
 import net.neoforged.bus.api.IEventBus;
 import net.neoforged.neoforge.registries.DeferredHolder;
@@ -28,17 +34,39 @@ public final class ModCreativeTabs {
                     })
                     .build());
 
-    public static final DeferredHolder<CreativeModeTab, CreativeModeTab> PAGES =
-            CREATIVE_TABS.register("rivencraft_pages", () -> CreativeModeTab.builder()
-                    .title(Component.translatable("itemGroup.rivencraft.pages"))
+    public static final DeferredHolder<CreativeModeTab, CreativeModeTab> LINK_PAGES =
+            CREATIVE_TABS.register("rivencraft_link_pages", () -> CreativeModeTab.builder()
+                    .title(Component.translatable("itemGroup.rivencraft.pages.link"))
                     .icon(PageItem::createLinkPanelPage)
-                    .displayItems((parameters, output) -> {
-                        output.accept(ModItems.PAGE.get());
-                        output.accept(PageItem.createLinkPanelPage());
-                        PageItem.creativeSymbolPages(parameters.holders()).forEach(output::accept);
-                    })
+                    .displayItems((parameters, output) -> output.accept(PageItem.createLinkPanelPage()))
                     .build());
 
+    private static final List<String> CATEGORY_ORDER = List.of(
+            "terrain", "biome", "biome_generation", "weather", "lighting", "sky", "celestial", "feature");
+
+    public static final Map<ResourceLocation, DeferredHolder<CreativeModeTab, CreativeModeTab>> SYMBOL_PAGES =
+            registerSymbolPageTabs();
+
+    private static Map<ResourceLocation, DeferredHolder<CreativeModeTab, CreativeModeTab>> registerSymbolPageTabs() {
+        List<ResourceLocation> categories = new ArrayList<>(PageItem.bundledCreativeCategories());
+        categories.sort(Comparator.comparingInt((ResourceLocation id) -> {
+            int index = CATEGORY_ORDER.indexOf(id.getPath());
+            return index < 0 ? CATEGORY_ORDER.size() : index;
+        }).thenComparing(ResourceLocation::toString));
+        Map<ResourceLocation, DeferredHolder<CreativeModeTab, CreativeModeTab>> tabs = new LinkedHashMap<>();
+        for (ResourceLocation category : categories) {
+            String key = "rivencraft_pages_" + category.getNamespace() + "_" + category.getPath().replace('/', '_');
+            tabs.put(category, CREATIVE_TABS.register(key, () -> CreativeModeTab.builder()
+                    .title(Component.translatableWithFallback("itemGroup.rivencraft.pages." + category.getPath(),
+                            "Rivencraft " + category.getPath() + " Pages"))
+                    .icon(() -> PageItem.bundledCreativeCategoryIcon(category))
+                    .displayItems((parameters, output) -> PageItem.creativeSymbolPages(parameters.holders(), category)
+                            .forEach(output::accept))
+                    .build()));
+        }
+        return Map.copyOf(tabs);
+    }
+
     private ModCreativeTabs() {
     }
 

src/main/resources/assets/rivencraft/lang/en_us.json

@@ -230,5 +230,13 @@
   "jei.rivencraft.writing.bind": "At a Book Binder, name the Age and add a cover plus Link Panel. Optional symbol Pages follow the panel.",
   "jei.rivencraft.writing.linking_book": "Craft one Link Panel Page with leather to make an unwritten Linking Book. Open it to name and bind it.",
   "itemGroup.rivencraft": "Rivencraft",
-  "itemGroup.rivencraft.pages": "Rivencraft Pages"
+  "itemGroup.rivencraft.pages.link": "Rivencraft Link Pages",
+  "itemGroup.rivencraft.pages.terrain": "Rivencraft Terrain Pages",
+  "itemGroup.rivencraft.pages.biome": "Rivencraft Biome Pages",
+  "itemGroup.rivencraft.pages.biome_generation": "Rivencraft Biome Generation Pages",
+  "itemGroup.rivencraft.pages.weather": "Rivencraft Weather Pages",
+  "itemGroup.rivencraft.pages.lighting": "Rivencraft Lighting Pages",
+  "itemGroup.rivencraft.pages.sky": "Rivencraft Sky Pages",
+  "itemGroup.rivencraft.pages.celestial": "Rivencraft Celestial Pages",
+  "itemGroup.rivencraft.pages.feature": "Rivencraft Feature Pages"
 }