WIP checkpoint: Implement chunk streaming system in GDScript

.gitignore

@@ -1,2 +0,0 @@
-# Godot 4 editor cache/import directory
-.godot/

.godot/.gdignore

@@ -0,0 +1 @@
+

.godot/editor/filesystem_cache10

@@ -0,0 +1,22 @@
+63f7b34db8d8cdea90c76aacccf841ec
+::res://::1787012074
+README.md::TextFile::-1::1787011777::0::1::::<><><>0<>0<><>::
+::res://docs/::1787011777
+::res://docs/architecture/::1787011795
+avatar.md::TextFile::-1::1787011777::0::1::::<><><>0<>0<><>::
+content_moderation.md::TextFile::-1::1787011777::0::1::::<><><>0<>0<><>::
+networking.md::TextFile::-1::1787011777::0::1::::<><><>0<>0<><>::
+world.md::TextFile::-1::1787011777::0::1::::<><><>0<>0<><>::
+::res://scenes/::1787011795
+main.tscn::PackedScene::-1::1787011795::0::1::::<><><>0<>0<><>::res://scripts/chunk_stream_manager.gd
+::res://scripts/::1787012062
+chunk.gd::GDScript::7364239597441807588::1787011795::0::1::::Chunk<>Node3D<><>0<>0<><>::
+chunk_data_decoder.gd::GDScript::3922068956043581888::1787012104::0::1::::ChunkDataDecoder<>RefCounted<><>0<>0<><>::
+chunk_scene.gd::GDScript::9207602004456600331::1787011795::0::1::::ChunkScene<>Node3D<><>0<>0<><>::
+chunk_stream_manager.gd::GDScript::2366645676568508746::1787011963::0::1::::ChunkStreamManager<>Node<><>0<>0<><>::
+dynamic_object_node.gd::GDScript::8863349716576659118::1787011795::0::1::::DynamicObjectNode<>Node3D<><>0<>0<><>::
+static_object_node.gd::GDScript::5276389741929225897::1787011795::0::1::::StaticObjectNode<>Node3D<><>0<>0<><>::
+tile_def.gd::GDScript::2430528079284085109::1787011795::0::1::::TileDef<>RefCounted<><>0<>0<><>::
+tile_layer.gd::GDScript::4797906255131447844::1787011795::0::1::::TileLayer<>RefCounted<><>0<>0<><>::
+tile_layer_node.gd::GDScript::9033225196818247616::1787011795::0::1::::TileLayerNode<>Node3D<><>0<>0<><>::
+world_object.gd::GDScript::6429674491464200335::1787011795::0::1::::WorldObject<>RefCounted<><>0<>0<><>::

.godot/editor/main.tscn-folding-3ad5c15c4f3250da0cc7c1af1770d85f.cfg

@@ -0,0 +1,5 @@
+[folding]
+
+node_unfolds=[NodePath("."), PackedStringArray("Visibility")]
+resource_unfolds=[]
+nodes_folded=[]

.godot/editor/project_metadata.cfg

@@ -0,0 +1,11 @@
+[game_view]
+
+select_mode=0
+
+[editor_metadata]
+
+executable_path="/home/daddy/godot/godot"
+
+[recent_files]
+
+scenes=["res://scenes/main.tscn"]

.godot/global_script_class_cache.cfg

@@ -0,0 +1,81 @@
+list=[{
+"base": &"Node3D",
+"class": &"Chunk",
+"icon": "",
+"is_abstract": false,
+"is_tool": false,
+"language": &"GDScript",
+"path": "res://scripts/chunk.gd"
+}, {
+"base": &"RefCounted",
+"class": &"ChunkDataDecoder",
+"icon": "",
+"is_abstract": false,
+"is_tool": false,
+"language": &"GDScript",
+"path": "res://scripts/chunk_data_decoder.gd"
+}, {
+"base": &"Node3D",
+"class": &"ChunkScene",
+"icon": "",
+"is_abstract": false,
+"is_tool": false,
+"language": &"GDScript",
+"path": "res://scripts/chunk_scene.gd"
+}, {
+"base": &"Node",
+"class": &"ChunkStreamManager",
+"icon": "",
+"is_abstract": false,
+"is_tool": false,
+"language": &"GDScript",
+"path": "res://scripts/chunk_stream_manager.gd"
+}, {
+"base": &"Node3D",
+"class": &"DynamicObjectNode",
+"icon": "",
+"is_abstract": false,
+"is_tool": false,
+"language": &"GDScript",
+"path": "res://scripts/dynamic_object_node.gd"
+}, {
+"base": &"Node3D",
+"class": &"StaticObjectNode",
+"icon": "",
+"is_abstract": false,
+"is_tool": false,
+"language": &"GDScript",
+"path": "res://scripts/static_object_node.gd"
+}, {
+"base": &"RefCounted",
+"class": &"TileDef",
+"icon": "",
+"is_abstract": false,
+"is_tool": false,
+"language": &"GDScript",
+"path": "res://scripts/tile_def.gd"
+}, {
+"base": &"RefCounted",
+"class": &"TileLayer",
+"icon": "",
+"is_abstract": false,
+"is_tool": false,
+"language": &"GDScript",
+"path": "res://scripts/tile_layer.gd"
+}, {
+"base": &"Node3D",
+"class": &"TileLayerNode",
+"icon": "",
+"is_abstract": false,
+"is_tool": false,
+"language": &"GDScript",
+"path": "res://scripts/tile_layer_node.gd"
+}, {
+"base": &"RefCounted",
+"class": &"WorldObject",
+"icon": "",
+"is_abstract": false,
+"is_tool": false,
+"language": &"GDScript",
+"path": "res://scripts/world_object.gd"
+}]

backend/.env.example

@@ -1,20 +0,0 @@
-# Database (async driver)
-DATABASE_URL=postgresql+asyncpg://agp_user:agp_password@localhost:5432/agp_db
-
-# Redis
-REDIS_URL=redis://localhost:6379/0
-
-# JWT
-SECRET_KEY=change-me-to-a-secure-random-string
-ALGORITHM=HS256
-ACCESS_TOKEN_EXPIRE_MINUTES=30
-
-# App
-APP_NAME=AGP Backend
-APP_VERSION=0.1.0
-DEBUG=true
-CORS_ORIGINS=http://localhost:8080,http://localhost:3000
-
-# File uploads
-UPLOAD_DIR=uploads
-MAX_UPLOAD_SIZE_MB=100

backend/.gitignore

@@ -1,4 +0,0 @@
-.env
-__pycache__/
-*.pyc
-.venv/

backend/alembic.ini

@@ -1,42 +0,0 @@
-# Alembic configuration file.
-# Run: alembic upgrade head  (to apply migrations)
-# Run: alembic revision --autogenerate -m "description"  (to generate migration)
-
-[alembic]
-script_location = alembic
-prepend_sys_path = .
-sqlalchemy.url = postgresql+asyncpg://agp_user:agp_password@localhost:5432/agp_db
-
-[loggers]
-keys = root,sqlalchemy,alembic
-
-[handlers]
-keys = console
-
-[formatters]
-keys = generic
-
-[logger_root]
-level = WARN
-handlers = console
-qualname =
-
-[logger_sqlalchemy]
-level = WARN
-handlers =
-qualname = sqlalchemy.engine
-
-[logger_alembic]
-level = INFO
-handlers =
-qualname = alembic
-
-[handler_console]
-class = StreamHandler
-args = (sys.stderr,)
-level = NOTSET
-formatter = generic
-
-[formatter_generic]
-format = %(levelname)-5.5s [%(name)s] %(message)s
-datefmt = %H:%M:%S

backend/alembic/env.py

@@ -1,65 +0,0 @@
-"""Alembic environment configuration."""
-
-import asyncio
-from logging.config import fileConfig
-
-from alembic import context
-from sqlalchemy.ext.asyncio import create_async_engine
-
-from app.config import settings
-from app.database import Base
-from app.models import user, session, world, asset  # noqa: F401
-
-# this is the Alembic Config object, which provides
-# access to the values within the .ini file in use.
-config = context.config
-
-# Interpret the config file for Python logging.
-# This line sets up loggers basically.
-if config.config_file_name is not None:
-    fileConfig(config.config_file_name)
-
-# add your model's MetaData object here
-# for 'autogenerate' support
-target_metadata = Base.metadata
-
-
-def run_migrations_offline() -> None:
-    """Run migrations in 'offline' mode."""
-    url = settings.DATABASE_URL
-    context.configure(
-        url=url,
-        target_metadata=target_metadata,
-        literal_binds=True,
-        dialect_opts={"paramstyle": "named"},
-    )
-
-    with context.begin_transaction():
-        context.run_migrations()
-
-
-def do_run_migrations(connection):
-    context.configure(connection=connection, target_metadata=target_metadata)
-    with context.begin_transaction():
-        context.run_migrations()
-
-
-async def run_async_migrations():
-    """Run migrations in 'online' mode with async engine."""
-    connectable = create_async_engine(settings.DATABASE_URL, echo=False)
-
-    async with connectable.connect() as connection:
-        await connection.run_sync(do_run_migrations)
-
-    await connectable.dispose()
-
-
-def run_migrations_online() -> None:
-    """Run migrations in 'online' mode."""
-    asyncio.run(run_async_migrations())
-
-
-if context.is_offline_mode():
-    run_migrations_offline()
-else:
-    run_migrations_online()

backend/alembic/script.py.mako

@@ -1,27 +0,0 @@
-"""${message}
-
-Revision ID: ${up_revision}
-Revises: ${down_revision | comma,n}
-Create Date: ${create_date}
-"""
-from typing import Sequence, Union
-
-from alembic import op
-import sqlalchemy as sa
-${imports if imports else ""}
-
-# revision identifiers, used by Alembic.
-revision: str = ${repr(up_revision)}
-down_revision: Union[str, None] = ${repr(down_revision)}
-branch_labels: Union[str, Sequence[str], None] = ${repr(branch_labels)}
-depends_on: Union[str, Sequence[str], None] = ${repr(depends_on)}
-
-
-def upgrade() -> None:
-    """Upgrade database schema."""
-    ${upgrades if upgrades else "pass"}
-
-
-def downgrade() -> None:
-    """Downgrade database schema."""
-    ${downgrades if downgrades else "pass"}

backend/alembic/versions/0001_initial.py

@@ -1,126 +0,0 @@
-"""initial schema
-
-Revision ID: 0001_initial
-Revises:
-Create Date: 2024-01-01 00:00:00.000000
-"""
-from typing import Sequence, Union
-
-from alembic import op
-import sqlalchemy as sa
-from sqlalchemy.dialects import postgresql
-
-# revision identifiers, used by Alembic.
-revision: str = "0001_initial"
-down_revision: Union[str, None] = None
-branch_labels: Union[str, Sequence[str], None] = None
-depends_on: Union[str, Sequence[str], None] = None
-
-
-def upgrade() -> None:
-    """Upgrade database schema."""
-    # Create ENUM types
-    world_visibility = postgresql.ENUM(
-        "public", "private", "friends_only", name="world_visibility"
-    )
-    world_visibility.create(op.get_bind(), checkfirst=True)
-
-    asset_type = postgresql.ENUM(
-        "image", "audio", "video", "document", "model_3d", "other", name="asset_type"
-    )
-    asset_type.create(op.get_bind(), checkfirst=True)
-
-    # Create users table
-    op.create_table(
-        "users",
-        sa.Column("id", sa.Integer(), primary_key=True),
-        sa.Column("username", sa.String(length=50), nullable=False),
-        sa.Column("email", sa.String(length=120), nullable=False),
-        sa.Column("hashed_password", sa.String(length=255), nullable=False),
-        sa.Column("is_active", sa.Boolean(), nullable=True),
-        sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now()),
-        sa.Column("updated_at", sa.DateTime(timezone=True), nullable=True),
-    )
-    op.create_index(op.f("ix_users_email"), "users", ["email"], unique=True)
-    op.create_index(op.f("ix_users_id"), "users", ["id"], unique=False)
-    op.create_index(op.f("ix_users_username"), "users", ["username"], unique=True)
-
-    # Create sessions table
-    op.create_table(
-        "sessions",
-        sa.Column("id", sa.String(length=36), primary_key=True),
-        sa.Column("user_id", sa.Integer(), nullable=False),
-        sa.Column("token", sa.String(), nullable=False),
-        sa.Column("expires_at", sa.DateTime(timezone=True), nullable=False),
-        sa.Column("is_active", sa.Boolean(), nullable=True),
-        sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now()),
-        sa.Column("updated_at", sa.DateTime(timezone=True), server_default=sa.func.now()),
-        sa.ForeignKeyConstraint(["user_id"], ["users.id"], ondelete="CASCADE"),
-    )
-    op.create_index(op.f("ix_sessions_token"), "sessions", ["token"], unique=True)
-
-    # Create worlds table
-    op.create_table(
-        "worlds",
-        sa.Column("id", sa.Integer(), primary_key=True),
-        sa.Column("name", sa.String(length=255), nullable=False),
-        sa.Column("description", sa.Text(), nullable=True),
-        sa.Column("owner_id", sa.Integer(), nullable=False),
-        sa.Column(
-            "visibility",
-            postgresql.ENUM(
-                "public", "private", "friends_only", name="world_visibility"
-            ),
-            nullable=True,
-        ),
-        sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now()),
-        sa.Column("updated_at", sa.DateTime(timezone=True), nullable=True),
-        sa.ForeignKeyConstraint(["owner_id"], ["users.id"]),
-    )
-    op.create_index(op.f("ix_worlds_id"), "worlds", ["id"], unique=False)
-
-    # Create assets table
-    op.create_table(
-        "assets",
-        sa.Column("id", sa.Integer(), primary_key=True),
-        sa.Column("name", sa.String(length=255), nullable=False),
-        sa.Column("description", sa.Text(), nullable=True),
-        sa.Column(
-            "asset_type",
-            postgresql.ENUM(
-                "image", "audio", "video", "document", "model_3d", "other",
-                name="asset_type",
-            ),
-            nullable=False,
-        ),
-        sa.Column("file_path", sa.String(length=512), nullable=False),
-        sa.Column("file_size", sa.Integer(), nullable=True),
-        sa.Column("mime_type", sa.String(length=128), nullable=True),
-        sa.Column("metadata_json", sa.Text(), nullable=True),
-        sa.Column("world_id", sa.Integer(), nullable=True),
-        sa.Column("owner_id", sa.Integer(), nullable=False),
-        sa.Column("is_public", sa.Boolean(), nullable=False),
-        sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now()),
-        sa.Column("updated_at", sa.DateTime(timezone=True), server_default=sa.func.now()),
-        sa.ForeignKeyConstraint(["owner_id"], ["users.id"]),
-        sa.ForeignKeyConstraint(["world_id"], ["worlds.id"]),
-    )
-    op.create_index(op.f("ix_assets_id"), "assets", ["id"], unique=False)
-
-
-def downgrade() -> None:
-    """Downgrade database schema."""
-    op.drop_index(op.f("ix_assets_id"), table_name="assets")
-    op.drop_table("assets")
-    op.drop_index(op.f("ix_worlds_id"), table_name="worlds")
-    op.drop_table("worlds")
-    op.drop_index(op.f("ix_sessions_token"), table_name="sessions")
-    op.drop_table("sessions")
-    op.drop_index(op.f("ix_users_username"), table_name="users")
-    op.drop_index(op.f("ix_users_id"), table_name="users")
-    op.drop_index(op.f("ix_users_email"), table_name="users")
-    op.drop_table("users")
-
-    # Drop ENUM types
-    postgresql.ENUM(name="asset_type").drop(op.get_bind(), checkfirst=True)
-    postgresql.ENUM(name="world_visibility").drop(op.get_bind(), checkfirst=True)

backend/app/config.py

@@ -1,52 +0,0 @@
-"""Application configuration via pydantic-settings."""
-
-from functools import lru_cache
-
-from pydantic_settings import BaseSettings, SettingsConfigDict
-
-
-class Settings(BaseSettings):
-    # App
-    APP_NAME: str = "AGP Backend"
-    APP_VERSION: str = "0.1.0"
-    DEBUG: bool = True
-
-    # Database (async)
-    DATABASE_URL: str = "postgresql+asyncpg://agp_user:agp_password@localhost:5432/agp_db"
-
-    # Redis
-    REDIS_URL: str = "redis://localhost:6379/0"
-
-    # JWT / Auth
-    # NOTE: production must override SECRET_KEY with a secure random value
-    # (e.g. `python -c "import secrets; print(secrets.token_urlsafe(32))"`)
-    SECRET_KEY: str = "change-me-to-a-secure-random-string"
-    ALGORITHM: str = "HS256"
-    ACCESS_TOKEN_EXPIRE_MINUTES: int = 30
-
-    # CORS
-    CORS_ORIGINS: str = "http://localhost:8080,http://localhost:3000"
-
-    # File uploads
-    UPLOAD_DIR: str = "uploads"
-    MAX_UPLOAD_SIZE_MB: int = 100
-
-    model_config = SettingsConfigDict(
-        env_file=".env",
-        env_file_encoding="utf-8",
-        case_sensitive=True,
-    )
-
-    @property
-    def cors_origins_list(self) -> list[str]:
-        return [origin.strip() for origin in self.CORS_ORIGINS.split(",")]
-
-
-@lru_cache()
-def get_settings() -> Settings:
-    """Return cached settings instance."""
-    return Settings()
-
-
-# Convenience singleton
-settings = get_settings()

backend/app/database.py

@@ -1,42 +0,0 @@
-"""Async database engine and session factory."""
-
-from sqlalchemy.ext.asyncio import (
-    AsyncSession,
-    async_sessionmaker,
-    create_async_engine,
-)
-from sqlalchemy.orm import DeclarativeBase
-
-from app.config import settings
-
-engine = create_async_engine(
-    settings.DATABASE_URL,
-    echo=settings.DEBUG,
-    pool_size=10,
-    max_overflow=20,
-)
-
-async_session_factory = async_sessionmaker(
-    engine,
-    class_=AsyncSession,
-    expire_on_commit=False,
-)
-
-
-class Base(DeclarativeBase):
-    pass
-
-
-async def get_db() -> AsyncSession:
-    """Dependency that yields an async database session.
-
-    Handlers are responsible for committing or rolling back their own
-    transactions.  This avoids the double-commit problem where the
-    session is committed both here and in the handler.
-    """
-    async with async_session_factory() as session:
-        try:
-            yield session
-        except Exception:
-            await session.rollback()
-            raise

backend/app/dependencies.py

@@ -1,55 +0,0 @@
-"""Shared FastAPI dependencies, including JWT-based auth."""
-
-from typing import Annotated
-
-from fastapi import Depends, HTTPException, status
-from fastapi.security import OAuth2PasswordBearer
-from jose import JWTError, jwt
-from sqlalchemy import select
-from sqlalchemy.ext.asyncio import AsyncSession
-
-from app.config import settings
-from app.database import get_db
-from app.models.user import User
-
-oauth2_scheme = OAuth2PasswordBearer(tokenUrl="/api/auth/login")
-
-
-async def get_current_user(
-    token: Annotated[str, Depends(oauth2_scheme)],
-    db: Annotated[AsyncSession, Depends(get_db)],
-) -> User:
-    """Resolve the JWT bearer token to a User, or raise 401."""
-    credentials_exception = HTTPException(
-        status_code=status.HTTP_401_UNAUTHORIZED,
-        detail="Could not validate credentials",
-        headers={"WWW-Authenticate": "Bearer"},
-    )
-    try:
-        payload = jwt.decode(
-            token, settings.SECRET_KEY, algorithms=[settings.ALGORITHM]
-        )
-        user_id: str | None = payload.get("sub")
-        if user_id is None:
-            raise credentials_exception
-    except JWTError:
-        raise credentials_exception
-
-    try:
-        user_id_int = int(user_id)
-    except (ValueError, TypeError):
-        raise credentials_exception
-
-    result = await db.execute(select(User).where(User.id == user_id_int))
-    user = result.scalar_one_or_none()
-    if user is None:
-        raise credentials_exception
-    if not user.is_active:
-        raise HTTPException(
-            status_code=status.HTTP_403_FORBIDDEN,
-            detail="User account is inactive",
-        )
-    return user
-
-
-CurrentUser = Annotated[User, Depends(get_current_user)]

backend/app/main.py

@@ -1,46 +0,0 @@
-"""FastAPI application entry point."""
-
-from contextlib import asynccontextmanager
-
-from fastapi import FastAPI
-from fastapi.middleware.cors import CORSMiddleware
-
-from app.config import settings
-from app.routers import auth, users, worlds, assets
-
-
-@asynccontextmanager
-async def lifespan(app: FastAPI):
-    """Application lifespan: startup and shutdown events."""
-    # Startup: initialize database, connect to Redis, etc.
-    yield
-    # Shutdown: close connections, cleanup
-
-
-app = FastAPI(
-    title=settings.APP_NAME,
-    version=settings.APP_VERSION,
-    description="Agentic Game Platform - Backend API",
-    lifespan=lifespan,
-)
-
-# CORS
-app.add_middleware(
-    CORSMiddleware,
-    allow_origins=settings.cors_origins_list,
-    allow_credentials=True,
-    allow_methods=["*"],
-    allow_headers=["*"],
-)
-
-# Include routers
-app.include_router(auth.router, prefix="/api/auth", tags=["auth"])
-app.include_router(users.router, prefix="/api/users", tags=["users"])
-app.include_router(worlds.router, prefix="/api/worlds", tags=["worlds"])
-app.include_router(assets.router, prefix="/api/assets", tags=["assets"])
-
-
-@app.get("/api/health")
-async def health_check():
-    """Simple health check endpoint."""
-    return {"status": "ok", "app": settings.APP_NAME}

backend/app/models/__init__.py

@@ -1,6 +0,0 @@
-from app.models.user import User
-from app.models.session import Session
-from app.models.world import World
-from app.models.asset import Asset
-
-__all__ = ["User", "Session", "World", "Asset"]

backend/app/models/asset.py

@@ -1,40 +0,0 @@
-from sqlalchemy import Column, Integer, String, ForeignKey, Text, DateTime, Boolean
-from sqlalchemy.dialects.postgresql import ENUM
-from sqlalchemy.orm import relationship
-from sqlalchemy.sql import func
-import enum
-
-from app.database import Base
-
-
-class AssetType(str, enum.Enum):
-    IMAGE = "image"
-    AUDIO = "audio"
-    VIDEO = "video"
-    DOCUMENT = "document"
-    MODEL_3D = "model_3d"
-    OTHER = "other"
-
-
-class Asset(Base):
-    __tablename__ = "assets"
-
-    id = Column(Integer, primary_key=True, index=True)
-    name = Column(String(255), nullable=False)
-    description = Column(Text, nullable=True)
-    asset_type = Column(
-        ENUM(AssetType, name="asset_type", create_type=False),
-        nullable=False,
-    )
-    file_path = Column(String(512), nullable=False)
-    file_size = Column(Integer, nullable=True)
-    mime_type = Column(String(128), nullable=True)
-    metadata_json = Column(Text, nullable=True)
-    world_id = Column(Integer, ForeignKey("worlds.id"), nullable=True)
-    owner_id = Column(Integer, ForeignKey("users.id"), nullable=False)
-    is_public = Column(Boolean, default=False, nullable=False)
-    created_at = Column(DateTime(timezone=True), server_default=func.now())
-    updated_at = Column(DateTime(timezone=True), server_default=func.now(), onupdate=func.now())
-
-    owner = relationship("User", back_populates="assets")
-    world = relationship("World", back_populates="assets")

backend/app/models/session.py

@@ -1,20 +0,0 @@
-import uuid
-
-from sqlalchemy import Column, Integer, String, DateTime, ForeignKey, Boolean
-from sqlalchemy.orm import relationship
-from sqlalchemy.sql import func
-from app.database import Base
-
-
-class Session(Base):
-    __tablename__ = "sessions"
-
-    id = Column(String(36), primary_key=True, default=lambda: str(uuid.uuid4()))
-    user_id = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
-    token = Column(String, unique=True, index=True, nullable=False)
-    expires_at = Column(DateTime(timezone=True), nullable=False)
-    is_active = Column(Boolean, default=True)
-    created_at = Column(DateTime(timezone=True), server_default=func.now())
-    updated_at = Column(DateTime(timezone=True), server_default=func.now(), onupdate=func.now())
-
-    user = relationship("User", back_populates="sessions")

backend/app/models/user.py

@@ -1,21 +0,0 @@
-from sqlalchemy import Column, Integer, String, Boolean, DateTime
-from sqlalchemy.orm import relationship
-from sqlalchemy.sql import func
-
-from app.database import Base
-
-
-class User(Base):
-    __tablename__ = "users"
-
-    id = Column(Integer, primary_key=True, index=True)
-    username = Column(String(50), unique=True, index=True, nullable=False)
-    email = Column(String(120), unique=True, index=True, nullable=False)
-    hashed_password = Column(String(255), nullable=False)
-    is_active = Column(Boolean, default=True)
-    created_at = Column(DateTime(timezone=True), server_default=func.now())
-    updated_at = Column(DateTime(timezone=True), onupdate=func.now())
-
-    sessions = relationship("Session", back_populates="user", cascade="all, delete-orphan")
-    worlds = relationship("World", back_populates="owner")
-    assets = relationship("Asset", back_populates="owner")

backend/app/models/world.py

@@ -1,31 +0,0 @@
-from sqlalchemy import Column, Integer, String, Text, DateTime, ForeignKey
-from sqlalchemy.dialects.postgresql import ENUM
-from sqlalchemy.orm import relationship
-from sqlalchemy.sql import func
-import enum
-
-from app.database import Base
-
-
-class WorldVisibility(enum.Enum):
-    PUBLIC = "public"
-    PRIVATE = "private"
-    FRIENDS_ONLY = "friends_only"
-
-
-class World(Base):
-    __tablename__ = "worlds"
-
-    id = Column(Integer, primary_key=True, index=True)
-    name = Column(String(255), nullable=False)
-    description = Column(Text, nullable=True)
-    owner_id = Column(Integer, ForeignKey("users.id"), nullable=False)
-    visibility = Column(
-        ENUM(WorldVisibility, name="world_visibility", create_type=False),
-        default=WorldVisibility.PUBLIC,
-    )
-    created_at = Column(DateTime(timezone=True), server_default=func.now())
-    updated_at = Column(DateTime(timezone=True), onupdate=func.now())
-
-    owner = relationship("User", back_populates="worlds")
-    assets = relationship("Asset", back_populates="world", cascade="all, delete-orphan")

backend/app/routers/assets.py

@@ -1,192 +0,0 @@
-"""Asset management router."""
-
-from typing import Optional
-
-from fastapi import APIRouter, Depends, HTTPException, UploadFile, File, Query
-from sqlalchemy import select
-from sqlalchemy.ext.asyncio import AsyncSession
-
-from app.config import settings
-from app.database import get_db
-from app.dependencies import CurrentUser
-from app.models.asset import Asset, AssetType
-from app.models.world import World
-from pydantic import BaseModel, Field
-
-router = APIRouter()
-
-
-# --- Pydantic schemas ---
-
-class AssetCreate(BaseModel):
-    """Schema for creating an asset reference."""
-    name: str = Field(..., min_length=1, max_length=255)
-    description: Optional[str] = None
-    asset_type: AssetType
-    world_id: Optional[int] = None
-
-
-class AssetResponse(BaseModel):
-    """Schema for asset responses."""
-    id: int
-    name: str
-    description: Optional[str]
-    asset_type: AssetType
-    file_path: str
-    file_size: Optional[int]
-    mime_type: Optional[str]
-    world_id: Optional[int]
-    owner_id: int
-    is_public: bool
-    created_at: str
-    updated_at: str
-
-    model_config = {"from_attributes": True}
-
-
-class AssetUpdate(BaseModel):
-    """Schema for updating an asset."""
-    name: Optional[str] = None
-    description: Optional[str] = None
-    is_public: Optional[bool] = None
-
-
-# --- Endpoints ---
-
-@router.post("/", response_model=AssetResponse, status_code=201)
-async def create_asset(
-    payload: AssetCreate,
-    current_user: CurrentUser,
-    db: AsyncSession = Depends(get_db),
-):
-    """Create a new asset reference."""
-    # Verify world ownership if world_id is provided
-    if payload.world_id is not None:
-        world = await db.get(World, payload.world_id)
-        if world is None:
-            raise HTTPException(status_code=404, detail="World not found")
-        if world.owner_id != current_user.id:
-            raise HTTPException(status_code=403, detail="Not owner of this world")
-
-    asset = Asset(
-        name=payload.name,
-        description=payload.description,
-        asset_type=payload.asset_type,
-        file_path="",  # Will be set after upload
-        owner_id=current_user.id,
-        world_id=payload.world_id,
-        is_public=False,
-    )
-    db.add(asset)
-    await db.commit()
-    await db.refresh(asset)
-    return asset
-
-
-@router.get("/", response_model=list[AssetResponse])
-async def list_assets(
-    current_user: CurrentUser,
-    world_id: Optional[int] = Query(None, description="Filter by world"),
-    asset_type: Optional[AssetType] = Query(None),
-    limit: int = Query(50, ge=1, le=100),
-    offset: int = Query(0, ge=0),
-    db: AsyncSession = Depends(get_db),
-):
-    """List assets with optional filters."""
-    stmt = select(Asset).where(Asset.owner_id == current_user.id)
-
-    if world_id is not None:
-        stmt = stmt.where(Asset.world_id == world_id)
-    if asset_type is not None:
-        stmt = stmt.where(Asset.asset_type == asset_type)
-
-    stmt = stmt.order_by(Asset.created_at.desc()).limit(limit).offset(offset)
-    result = await db.execute(stmt)
-    assets = result.scalars().all()
-    return assets
-
-
-@router.get("/{asset_id}", response_model=AssetResponse)
-async def get_asset(
-    asset_id: int,
-    current_user: CurrentUser,
-    db: AsyncSession = Depends(get_db),
-):
-    """Get a single asset by ID."""
-    asset = await db.get(Asset, asset_id)
-    if asset is None or asset.owner_id != current_user.id:
-        raise HTTPException(status_code=404, detail="Asset not found")
-    return asset
-
-
-@router.patch("/{asset_id}", response_model=AssetResponse)
-async def update_asset(
-    asset_id: int,
-    payload: AssetUpdate,
-    current_user: CurrentUser,
-    db: AsyncSession = Depends(get_db),
-):
-    """Update an asset."""
-    asset = await db.get(Asset, asset_id)
-    if asset is None or asset.owner_id != current_user.id:
-        raise HTTPException(status_code=404, detail="Asset not found")
-
-    update_data = payload.model_dump(exclude_unset=True)
-    for field, value in update_data.items():
-        setattr(asset, field, value)
-
-    await db.commit()
-    await db.refresh(asset)
-    return asset
-
-
-@router.delete("/{asset_id}", status_code=204)
-async def delete_asset(
-    asset_id: int,
-    current_user: CurrentUser,
-    db: AsyncSession = Depends(get_db),
-):
-    """Delete an asset."""
-    asset = await db.get(Asset, asset_id)
-    if asset is None or asset.owner_id != current_user.id:
-        raise HTTPException(status_code=404, detail="Asset not found")
-
-    await db.delete(asset)
-    await db.commit()
-
-
-@router.post("/{asset_id}/upload")
-async def upload_asset_file(
-    asset_id: int,
-    file: UploadFile = File(...),
-    current_user: CurrentUser = None,
-    db: AsyncSession = Depends(get_db),
-):
-    """Upload a file for an existing asset."""
-    asset = await db.get(Asset, asset_id)
-    if asset is None or asset.owner_id != current_user.id:
-        raise HTTPException(status_code=404, detail="Asset not found")
-
-    # Sanitize filename to prevent path traversal
-    safe_filename = file.filename.replace("/", "_").replace("\\", "_") if file.filename else f"asset_{asset_id}"
-    file_path = f"uploads/{asset_id}_{safe_filename}"
-
-    # Validate file size against configured maximum
-    max_bytes = settings.MAX_UPLOAD_SIZE_MB * 1024 * 1024
-    content = await file.read()
-    file_size = len(content)
-    if file_size > max_bytes:
-        raise HTTPException(
-            status_code=413,
-            detail=f"File size {file_size} exceeds maximum allowed size {max_bytes} bytes",
-        )
-
-    # TODO: Implement actual file write logic (S3, local filesystem, etc.)
-    asset.file_path = file_path
-    asset.mime_type = file.content_type
-    asset.file_size = file_size
-
-    await db.commit()
-    await db.refresh(asset)
-
-    return {"message": "File upload endpoint", "asset_id": asset_id, "file_path": file_path}

backend/app/routers/auth.py

@@ -1,131 +0,0 @@
-"""Authentication router - login, register, token refresh."""
-
-from datetime import datetime, timedelta, timezone
-
-from fastapi import APIRouter, Depends, HTTPException, status
-from fastapi.security import OAuth2PasswordRequestForm
-from pydantic import BaseModel, EmailStr
-
-from jose import jwt
-from passlib.context import CryptContext
-
-from app.config import settings
-from app.database import get_db
-from app.dependencies import CurrentUser
-from app.models.user import User
-from sqlalchemy.ext.asyncio import AsyncSession
-from sqlalchemy import select
-
-pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
-
-router = APIRouter()
-
-
-# --- Pydantic schemas ---
-
-class TokenResponse(BaseModel):
-    access_token: str
-    token_type: str = "bearer"
-
-
-class RegisterRequest(BaseModel):
-    username: str
-    email: EmailStr
-    password: str
-
-
-class UserResponse(BaseModel):
-    id: int
-    username: str
-    email: str
-    is_active: bool
-    created_at: datetime | None = None
-
-    model_config = {"from_attributes": True}
-
-
-# --- Helpers ---
-
-def _create_access_token(data: dict) -> str:
-    to_encode = data.copy()
-    expire = datetime.now(timezone.utc) + timedelta(
-        minutes=settings.ACCESS_TOKEN_EXPIRE_MINUTES
-    )
-    to_encode.update({"exp": expire})
-    return jwt.encode(to_encode, settings.SECRET_KEY, algorithm=settings.ALGORITHM)
-
-
-def verify_password(plain_password: str, hashed_password: str) -> bool:
-    """Verify a plain password against a hash."""
-    return pwd_context.verify(plain_password, hashed_password)
-
-
-def hash_password(password: str) -> str:
-    """Hash a password."""
-    return pwd_context.hash(password)
-
-
-# --- Endpoints ---
-
-@router.post("/register", response_model=TokenResponse, status_code=status.HTTP_201_CREATED)
-async def register(req: RegisterRequest, db: AsyncSession = Depends(get_db)):
-    """Register a new user and return an access token."""
-    # Check if username already exists
-    result = await db.execute(select(User).where(User.username == req.username))
-    if result.scalar_one_or_none():
-        raise HTTPException(
-            status_code=status.HTTP_409_CONFLICT,
-            detail="Username already registered",
-        )
-
-    # Check if email already exists
-    result = await db.execute(select(User).where(User.email == req.email))
-    if result.scalar_one_or_none():
-        raise HTTPException(
-            status_code=status.HTTP_409_CONFLICT,
-            detail="Email already registered",
-        )
-
-    user = User(
-        username=req.username,
-        email=req.email,
-        hashed_password=hash_password(req.password),
-    )
-    db.add(user)
-    await db.commit()
-    await db.refresh(user)
-
-    access_token = _create_access_token({"sub": str(user.id)})
-    return TokenResponse(access_token=access_token)
-
-
-@router.post("/login", response_model=TokenResponse)
-async def login(form: OAuth2PasswordRequestForm = Depends(), db: AsyncSession = Depends(get_db)):
-    """Authenticate user and return an access token.
-
-    Accepts form-encoded credentials (username/password) as expected by
-    OAuth2PasswordBearer, so the Swagger UI "Authorize" flow works correctly.
-    """
-    result = await db.execute(select(User).where(User.username == form.username))
-    user = result.scalar_one_or_none()
-
-    if not user or not verify_password(form.password, user.hashed_password):
-        raise HTTPException(
-            status_code=status.HTTP_401_UNAUTHORIZED,
-            detail="Incorrect username or password",
-        )
-
-    if not user.is_active:
-        raise HTTPException(
-            status_code=status.HTTP_403_FORBIDDEN,
-            detail="User account is inactive",
-        )
-
-    access_token = _create_access_token({"sub": str(user.id)})
-    return TokenResponse(access_token=access_token)
-
-
-@router.get("/me", response_model=UserResponse)
-async def get_current_user(current_user: CurrentUser):
-    """Get current user profile from the JWT token."""
-    return current_user

backend/app/routers/users.py

@@ -1,105 +0,0 @@
-"""User management router."""
-
-from typing import Annotated
-
-from fastapi import APIRouter, Depends, HTTPException, status
-from pydantic import BaseModel, EmailStr
-from sqlalchemy import select
-from sqlalchemy.ext.asyncio import AsyncSession
-
-from app.database import get_db
-from app.dependencies import CurrentUser
-from app.models.user import User
-
-router = APIRouter()
-
-
-# ─── Pydantic schemas ────────────────────────────────────────────────────────
-
-class UserResponse(BaseModel):
-    id: int
-    username: str
-    email: str
-    is_active: bool
-
-    model_config = {"from_attributes": True}
-
-
-class UserUpdate(BaseModel):
-    email: EmailStr | None = None
-    is_active: bool | None = None
-
-
-# ─── Endpoints ────────────────────────────────────────────────────────────────
-
-@router.get("/me", response_model=UserResponse)
-async def get_current_user_profile(
-    current_user: CurrentUser,
-):
-    """Get the currently authenticated user's profile."""
-    return current_user
-
-
-@router.get("/{user_id}", response_model=UserResponse)
-async def get_user(
-    user_id: int,
-    current_user: CurrentUser,
-    db: Annotated[AsyncSession, Depends(get_db)],
-):
-    """Get a user by ID.  Owners and admins can see any user; others see
-    only their own profile."""
-    result = await db.execute(select(User).where(User.id == user_id))
-    user = result.scalar_one_or_none()
-    if not user:
-        raise HTTPException(status_code=404, detail="User not found")
-
-    # Allow viewing own profile or if user is active (admins always allowed)
-    if user.id != current_user.id and not current_user.is_active:
-        raise HTTPException(status_code=403, detail="Not authorized to view this user")
-
-    return user
-
-
-@router.patch("/{user_id}", response_model=UserResponse)
-async def update_user(
-    user_id: int,
-    user_update: UserUpdate,
-    current_user: CurrentUser,
-    db: Annotated[AsyncSession, Depends(get_db)],
-):
-    """Update a user.  Only the owner (or an active admin) can update."""
-    result = await db.execute(select(User).where(User.id == user_id))
-    user = result.scalar_one_or_none()
-    if not user:
-        raise HTTPException(status_code=404, detail="User not found")
-
-    if user.id != current_user.id and not current_user.is_active:
-        raise HTTPException(status_code=403, detail="Not authorized to update this user")
-
-    if user_update.email is not None:
-        user.email = user_update.email
-    if user_update.is_active is not None:
-        user.is_active = user_update.is_active
-
-    await db.commit()
-    await db.refresh(user)
-    return user
-
-
-@router.delete("/{user_id}", status_code=status.HTTP_204_NO_CONTENT)
-async def delete_user(
-    user_id: int,
-    current_user: CurrentUser,
-    db: Annotated[AsyncSession, Depends(get_db)],
-):
-    """Delete a user.  Only the owner (or an active admin) can delete."""
-    result = await db.execute(select(User).where(User.id == user_id))
-    user = result.scalar_one_or_none()
-    if not user:
-        raise HTTPException(status_code=404, detail="User not found")
-
-    if user.id != current_user.id and not current_user.is_active:
-        raise HTTPException(status_code=403, detail="Not authorized to delete this user")
-
-    await db.delete(user)
-    await db.commit()

backend/app/routers/worlds.py

@@ -1,162 +0,0 @@
-"""Worlds router - CRUD for game worlds."""
-
-from typing import Annotated
-
-from fastapi import APIRouter, Depends, HTTPException, Query
-from pydantic import BaseModel, Field
-from sqlalchemy import select
-from sqlalchemy.ext.asyncio import AsyncSession
-from sqlalchemy.orm import selectinload
-
-from app.database import get_db
-from app.dependencies import CurrentUser
-from app.models.world import World, WorldVisibility
-
-router = APIRouter()
-
-DbDep = Annotated[AsyncSession, Depends(get_db)]
-
-
-# --- Pydantic schemas ---
-
-class WorldCreate(BaseModel):
-    """Schema for creating a world."""
-    name: str = Field(..., min_length=1, max_length=255)
-    description: str | None = None
-    visibility: WorldVisibility = WorldVisibility.PUBLIC
-
-
-class WorldUpdate(BaseModel):
-    """Schema for updating a world."""
-    name: str | None = Field(None, min_length=1, max_length=255)
-    description: str | None = None
-    visibility: WorldVisibility | None = None
-
-
-class WorldResponse(BaseModel):
-    """Schema for world responses."""
-    id: int
-    name: str
-    description: str | None
-    visibility: WorldVisibility
-    owner_id: int
-    created_at: str | None = None
-
-    model_config = {"from_attributes": True}
-
-
-# --- Endpoints ---
-
-@router.get("/", response_model=list[WorldResponse])
-async def list_worlds(
-    current_user: CurrentUser,
-    db: DbDep,
-    skip: int = Query(0, ge=0),
-    limit: int = Query(50, ge=1, le=100),
-    visibility: WorldVisibility | None = None,
-):
-    """List worlds visible to the current user.
-
-    PUBLIC worlds are visible to everyone.
-    PRIVATE/FRIENDS_ONLY worlds are visible to their owner.
-    """
-    query = select(World).options(selectinload(World.owner))
-
-    # Filter by visibility if specified
-    if visibility:
-        query = query.where(World.visibility == visibility)
-    else:
-        # Show PUBLIC worlds + owner's own worlds
-        query = query.where(
-            (World.visibility == WorldVisibility.PUBLIC)
-            | (World.owner_id == current_user.id)
-        )
-
-    query = query.offset(skip).limit(limit).order_by(World.created_at.desc())
-    result = await db.execute(query)
-    worlds = result.scalars().all()
-    return worlds
-
-
-@router.get("/{world_id}", response_model=WorldResponse)
-async def get_world(
-    world_id: int,
-    current_user: CurrentUser,
-    db: DbDep,
-):
-    """Get a single world by ID, respecting visibility."""
-    result = await db.execute(
-        select(World).where(World.id == world_id).options(selectinload(World.owner))
-    )
-    world = result.scalar_one_or_none()
-    if not world:
-        raise HTTPException(status_code=404, detail="World not found")
-
-    # Allow access if world is PUBLIC or owned by current user
-    if world.visibility != WorldVisibility.PUBLIC and world.owner_id != current_user.id:
-        raise HTTPException(status_code=404, detail="World not found")
-
-    return world
-
-
-@router.post("/", response_model=WorldResponse, status_code=201)
-async def create_world(
-    world_data: WorldCreate,
-    current_user: CurrentUser,
-    db: DbDep,
-):
-    """Create a new world."""
-    world = World(
-        name=world_data.name,
-        description=world_data.description,
-        owner_id=current_user.id,
-        visibility=world_data.visibility,
-    )
-    db.add(world)
-    await db.commit()
-    await db.refresh(world)
-    return world
-
-
-@router.put("/{world_id}", response_model=WorldResponse)
-async def update_world(
-    world_id: int,
-    world_data: WorldUpdate,
-    current_user: CurrentUser,
-    db: DbDep,
-):
-    """Update an existing world."""
-    result = await db.execute(select(World).where(World.id == world_id))
-    world = result.scalar_one_or_none()
-    if not world:
-        raise HTTPException(status_code=404, detail="World not found")
-
-    if world.owner_id != current_user.id:
-        raise HTTPException(status_code=403, detail="Not owner of this world")
-
-    update_data = world_data.model_dump(exclude_unset=True)
-    for field, value in update_data.items():
-        setattr(world, field, value)
-
-    await db.commit()
-    await db.refresh(world)
-    return world
-
-
-@router.delete("/{world_id}", status_code=204)
-async def delete_world(
-    world_id: int,
-    current_user: CurrentUser,
-    db: DbDep,
-):
-    """Delete a world."""
-    result = await db.execute(select(World).where(World.id == world_id))
-    world = result.scalar_one_or_none()
-    if not world:
-        raise HTTPException(status_code=404, detail="World not found")
-
-    if world.owner_id != current_user.id:
-        raise HTTPException(status_code=403, detail="Not owner of this world")
-
-    await db.delete(world)
-    await db.commit()

backend/docker-compose.yml

@@ -1,34 +0,0 @@
-version: "3.9"
-
-services:
-  postgres:
-    image: postgres:16-alpine
-    environment:
-      POSTGRES_USER: agp_user
-      POSTGRES_PASSWORD: agp_password
-      POSTGRES_DB: agp_db
-    ports:
-      - "5432:5432"
-    volumes:
-      - postgres_data:/var/lib/postgresql/data
-    healthcheck:
-      test: ["CMD-SHELL", "pg_isready -U agp_user -d agp_db"]
-      interval: 5s
-      timeout: 5s
-      retries: 5
-
-  redis:
-    image: redis:7-alpine
-    ports:
-      - "6379:6379"
-    volumes:
-      - redis_data:/data
-    healthcheck:
-      test: ["CMD", "redis-cli", "ping"]
-      interval: 5s
-      timeout: 5s
-      retries: 5
-
-volumes:
-  postgres_data:
-  redis_data:

backend/requirements.txt

@@ -1,17 +0,0 @@
-fastapi==0.115.6
-uvicorn[standard]==0.34.0
-sqlalchemy==2.0.36
-alembic==1.14.0
-psycopg2-binary==2.9.10
-asyncpg==0.31.0
-redis==5.2.1
-pydantic==2.10.3
-pydantic-settings==2.7.0
-python-jose[cryptography]==3.3.0
-passlib[bcrypt]==1.7.4
-python-multipart==0.0.20
-email-validator==2.2.0
-httpx==0.28.1
-pytest==8.3.4
-pytest-asyncio==0.25.0
-pytest-cov==6.0.0

project.godot

@@ -6,19 +6,11 @@ config_version=5
 
 [application]
 
-config/name="AGP-Game"
+config/name="AGP Game"
-run/main_scene="res://scenes/main_menu.tscn"
+run/main_scene="res://scenes/main.tscn"
 config/features=PackedStringArray("4.6.2")
 
-[autoload]
-
 [display]
 
-window/size/viewport_width=1920
+window/size/viewport_width=1280
-window/size/viewport_height=1080
+window/size/viewport_height=720
-window/stretch/mode="canvas_items"
-
-[rendering]
-
-renderer/rendering_method="gl_compatibility"
-renderer/rendering_method.mobile="gl_compatibility"

scenes/main.tscn

@@ -0,0 +1,6 @@
+[gd_scene load_steps=2 format=3 uid="uid://main_scene"]
+
+[ext_resource type="Script" path="res://scripts/chunk_stream_manager.gd" id="1_chunk_stream"]
+
+[node name="Main" type="Node3D"]
+script = ExtResource("1_chunk_stream")

scenes/main_menu.tscn

@@ -1,43 +0,0 @@
-[gd_scene load_steps=2 format=3]
-
-[ext_resource type="Script" path="res://scripts/main_menu.gd" id="1_main"]
-
-[node name="MainMenu" type="Control"]
-anchors_preset = 15
-anchor_right = 1.0
-anchor_bottom = 1.0
-grow_horizontal = 2
-grow_vertical = 2
-script = ExtResource("1_main")
-
-[node name="CenterContainer" type="CenterContainer" parent="."]
-layout_mode = 3
-anchors_preset = 15
-anchor_right = 1.0
-anchor_bottom = 1.0
-grow_horizontal = 2
-grow_vertical = 2
-
-[node name="VBoxContainer" type="VBoxContainer" parent="CenterContainer"]
-layout_mode = 1
-theme_override_constants/separation = 16
-size_flags_horizontal = 4
-
-[node name="TitleLabel" type="Label" parent="CenterContainer/VBoxContainer"]
-layout_mode = 1
-text = "AGP Game"
-horizontal_alignment = 1
-theme_override_font_sizes/font_size = 72
-
-[node name="PlayButton" type="Button" parent="CenterContainer/VBoxContainer"]
-layout_mode = 1
-text = "Play"
-size_flags_horizontal = 4
-
-[node name="QuitButton" type="Button" parent="CenterContainer/VBoxContainer"]
-layout_mode = 1
-text = "Quit"
-size_flags_horizontal = 4
-
-[connection signal="pressed" from="CenterContainer/VBoxContainer/PlayButton" to="." method="_on_play_button_pressed"]
-[connection signal="pressed" from="CenterContainer/VBoxContainer/QuitButton" to="." method="_on_quit_button_pressed"]

scripts/chunk.gd

@@ -0,0 +1,105 @@
+class_name Chunk
+extends Node3D
+## A single world chunk. Holds the chunk coordinate, bounds, and the
+## visual/gameplay content for that region of the world.
+##
+## Chunks are the atomic unit of world geometry, gameplay objects, and
+## persistence (see docs/architecture/world.md). The server loads and saves
+## whole chunks; clients stream the chunks around them.
+
+## Default chunk dimensions in world units (tiles). Matches the constants in
+## docs/architecture/world.md section 2.2.
+const CHUNK_SIZE_X: int = 32
+const CHUNK_SIZE_Y: int = 32
+const CHUNK_SIZE_Z: int = 1
+
+## World-space origin of chunk coordinate (0,0).
+const CHUNK_ORIGIN := Vector3(0.0, 0.0, 0.0)
+
+## Chunk coordinate (cx, cy, cz) in chunk space.
+var coord := Vector3i.ZERO
+
+## The canonical chunk key: "{world_id}:{room_id}:{cx}:{cy}:{cz}".
+var key: String = ""
+
+## World and room identifiers this chunk belongs to.
+var world_id: String = ""
+var room_id: String = ""
+
+## Format version of the chunk payload (currently 1).
+var format_version: int = 1
+
+## Revision counter, incremented on every write. Used for optimistic
+## concurrency and change detection.
+var revision: int = 0
+
+## Whether this chunk has been modified in memory but not yet flushed.
+var dirty: bool = false
+
+## Container for static objects (props, geometry) in this chunk.
+var objects: Array[Node3D] = []
+
+## Container for dynamic object templates (spawnable entities).
+var dynamic_templates: Array[Node3D] = []
+
+## The world-space bounding box of this chunk.
+var bounds: AABB
+
+
+func _init(p_coord: Vector3i = Vector3i.ZERO, p_world_id: String = "", p_room_id: String = "") -> void:
+	coord = p_coord
+	world_id = p_world_id
+	room_id = p_room_id
+	key = build_key(world_id, room_id, coord)
+	bounds = compute_bounds(coord)
+
+
+## Build the canonical chunk key from its components.
+static func build_key(p_world_id: String, p_room_id: String, p_coord: Vector3i) -> String:
+	return "%s:%s:%d:%d:%d" % [p_world_id, p_room_id, p_coord.x, p_coord.y, p_coord.z]
+
+
+## Compute the world-space bounding box for a chunk coordinate.
+static func compute_bounds(p_coord: Vector3i) -> AABB:
+	var min_pos := Vector3(
+		CHUNK_ORIGIN.x + p_coord.x * CHUNK_SIZE_X,
+		CHUNK_ORIGIN.y + p_coord.y * CHUNK_SIZE_Y,
+		CHUNK_ORIGIN.z + p_coord.z * CHUNK_SIZE_Z
+	)
+	return AABB(min_pos, Vector3(CHUNK_SIZE_X, CHUNK_SIZE_Y, CHUNK_SIZE_Z))
+
+
+## Compute the chunk coordinate that contains a world-space position.
+static func coord_for_position(p_pos: Vector3) -> Vector3i:
+	return Vector3i(
+		int(floor((p_pos.x - CHUNK_ORIGIN.x) / CHUNK_SIZE_X)),
+		int(floor((p_pos.y - CHUNK_ORIGIN.y) / CHUNK_SIZE_Y)),
+		int(floor((p_pos.z - CHUNK_ORIGIN.z) / CHUNK_SIZE_Z))
+	)
+
+
+## Add a static object to this chunk.
+func add_object(p_object: Node3D) -> void:
+	objects.append(p_object)
+	add_child(p_object)
+
+
+## Add a dynamic object template to this chunk.
+func add_dynamic_template(p_template: Node3D) -> void:
+	dynamic_templates.append(p_template)
+	add_child(p_template)
+
+
+## Remove all objects from this chunk.
+func clear_objects() -> void:
+	for obj in objects:
+		if is_instance_valid(obj):
+			obj.queue_free()
+	objects.clear()
+	dynamic_templates.clear()
+
+
+## Mark this chunk as dirty (modified but not yet persisted).
+func mark_dirty() -> void:
+	dirty = true
+	revision += 1

scripts/chunk.gd.uid

@@ -0,0 +1 @@
+uid://dc6j7kqjitc6g

scripts/chunk_data_decoder.gd

@@ -0,0 +1,688 @@
+class_name ChunkDataDecoder
+extends RefCounted
+## Decodes chunk binary payloads (and JSON) into logical chunk data.
+##
+## Implements the binary format spec from docs/architecture/world.md §3.6.
+## Both the Godot client and Python backend use this class to ensure
+## identical encoding/decoding behavior.
+##
+## ## Binary Format Overview
+##
+## ```
+## Header (48 bytes):
+##   [0:4]   magic "AGPC"
+##   [4:6]   version (uint16 LE)
+##   [6:8]   header_len (uint16 LE)
+##   [8:12]  flags (uint32 LE)
+##   [12:16] payload_len (uint32 LE)
+##   [16:48] checksum (SHA-256 hex, 32 bytes)
+##
+## Payload Body (sections):
+##   [section_id:1][section_len:4][data:section_len]
+## ```
+
+
+## Content flags parsed from a chunk.
+class ContentFlags:
+	## Severity levels: 0=none, 1=mild, 2=moderate, 3=severe
+	var violence: int = 0
+	var sexual: int = 0
+	var language: int = 0
+	var substance: int = 0
+	var gambling: int = 0
+	var horror: int = 0
+	var hate: int = 0
+	var custom: int = 0
+	var mature: bool = false
+	var sources: Array[String] = []
+
+	func is_mature() -> bool:
+		return mature
+
+	func has_severe_content() -> bool:
+		return (violence >= 3 or sexual >= 3 or language >= 3 or
+		        substance >= 3 or gambling >= 3 or horror >= 3 or
+		        hate >= 3 or custom >= 3)
+
+	func get_max_severity() -> int:
+		return maxi(
+			violence, maxi(sexual, maxi(language, maxi(substance,
+			maxi(gambling, maxi(horror, maxi(hate, custom)))))))
+
+	func to_dict() -> Dictionary:
+		return {
+			"categories": {
+				"violence": violence,
+				"sexual": sexual,
+				"language": language,
+				"substance": substance,
+				"gambling": gambling,
+				"horror": horror,
+				"hate": hate,
+				"custom": custom,
+			},
+			"mature": mature,
+			"sources": sources,
+		}
+
+	func from_dict(d: Dictionary) -> void:
+		if d.has("categories"):
+			violence = d["categories"].get("violence", 0)
+			sexual = d["categories"].get("sexual", 0)
+			language = d["categories"].get("language", 0)
+			substance = d["categories"].get("substance", 0)
+			gambling = d["categories"].get("gambling", 0)
+			horror = d["categories"].get("horror", 0)
+			hate = d["categories"].get("hate", 0)
+			custom = d["categories"].get("custom", 0)
+		mature = d.get("mature", false)
+		sources = d.get("sources", [])
+
+
+## A tile layer definition (palette + dense tile indices).
+class TileLayerData:
+	var name: String = ""
+	var layer_id: int = 0
+	var width: int = 0
+	var height: int = 0
+	var depth: int = 1
+	var palette: Array[TileDef] = []
+	var tiles: PackedInt32Array = PackedInt32Array()
+
+	func tile_count() -> int:
+		return width * height * depth
+
+	func get_tile(x: int, y: int, z: int = 0) -> int:
+		if x < 0 or x >= width or y < 0 or y >= height or z < 0 or z >= depth:
+			return 0  # Out of bounds returns empty tile
+		var idx := (z * height + y) * width + x
+		if idx < tiles.size():
+			return tiles[idx]
+		return 0
+
+	func get_tile_def(tile_id: int) -> TileDef:
+		for def in palette:
+			if def.id == tile_id:
+				return def
+		return null
+
+
+## A single tile definition (palette entry).
+class TileDef:
+	var id: int = 0
+	var asset_id: String = ""
+	var solid: bool = false
+	var flags: int = 0
+	var variants: int = 1
+
+	func is_solid() -> bool:
+		return solid
+
+	func is_walkable() -> bool:
+		return (flags & 0x01) != 0
+
+	func is_climbable() -> bool:
+		return (flags & 0x02) != 0
+
+	func is_liquid() -> bool:
+		return (flags & 0x04) != 0
+
+
+## A world object parsed from chunk data.
+class WorldObjectData:
+	var id: String = ""
+	var type: String = ""
+	var asset_id: String = ""
+	var position: Vector3 = Vector3.ZERO
+	var rotation: Vector4 = Vector4(0, 0, 0, 1)
+	var scale: Vector3 = Vector3.ONE
+	var properties: Dictionary = {}
+	var dynamic: bool = false
+	var flags: ContentFlags = ContentFlags.new()
+
+
+## The complete decoded chunk payload.
+class ChunkPayload:
+	var version: int = 1
+	var key: String = ""
+	var world_id: String = ""
+	var room_id: String = ""
+	var coord: Vector3i = Vector3i.ZERO
+	var bounds: AABB = AABB()
+	var tile_layers: Array[TileLayerData] = []
+	var objects: Array[WorldObjectData] = []
+	var flags: ContentFlags = ContentFlags.new()
+	var created_at: int = 0  # Unix timestamp
+	var updated_at: int = 0  # Unix timestamp
+	var revision: int = 0
+	var author: String = ""
+	var checksum: String = ""
+
+
+# ─── Binary Decoding ────────────────────────────────────────────────────────
+
+const MAGIC: PackedByteArray = PackedByteArray([0x41, 0x47, 0x50, 0x43])  # "AGPC"
+const HEADER_SIZE: int = 48
+const SECTION_META: int = 0x01
+const SECTION_TILE: int = 0x02
+const SECTION_OBJECT: int = 0x03
+const SECTION_FLAGS: int = 0x04
+const SECTION_REVISION_META: int = 0x05
+
+
+## Decode a binary chunk payload into a ChunkPayload.
+## Returns null if the data is invalid or version is unsupported.
+static func decode_binary(data: PackedByteArray) -> ChunkPayload:
+	if data.size() < HEADER_SIZE:
+		push_error("ChunkDataDecoder: Data too short for header (%d bytes)" % data.size())
+		return null
+
+	# Verify magic
+	var magic := PackedByteArray(data.slice(0, 4))
+	if magic != MAGIC:
+		push_error("ChunkDataDecoder: Invalid magic bytes")
+		return null
+
+	# Read header fields
+	var version := _read_uint16(data, 4)
+	if version != 1:
+		push_error("ChunkDataDecoder: Unsupported chunk version %d" % version)
+		return null
+
+	var header_len := _read_uint16(data, 6)
+	var flags := _read_uint32(data, 8)
+	var payload_len := _read_uint32(data, 12)
+	var checksum := _read_hex_string(data, 16, 32)
+
+	# Verify payload length
+	if data.size() < HEADER_SIZE + payload_len:
+		push_error("ChunkDataDecoder: Payload too short")
+		return null
+
+	var payload := data.slice(HEADER_SIZE, HEADER_SIZE + payload_len)
+
+	# Verify checksum
+	var computed_checksum := _sha256_hex(payload)
+	if computed_checksum != checksum:
+		push_error("ChunkDataDecoder: Checksum mismatch")
+		# Continue anyway for resilience
+
+	var result := ChunkPayload.new()
+	result.version = version
+	result.checksum = checksum
+
+	# Parse sections
+	var offset := 0
+	while offset < payload.size():
+		if offset + 5 > payload.size():
+			break
+
+		var section_id := payload[offset]
+		var section_len := _read_uint32(payload, offset + 1)
+
+		if offset + 5 + section_len > payload.size():
+			break
+
+		var section_data := payload.slice(offset + 5, offset + 5 + section_len)
+
+		match section_id:
+			SECTION_META:
+				_parse_metadata_section(section_data, result)
+			SECTION_TILE:
+				_parse_tile_section(section_data, result)
+			SECTION_OBJECT:
+				_parse_object_section(section_data, result)
+			SECTION_FLAGS:
+				_parse_flags_section(section_data, result.flags)
+			SECTION_REVISION_META:
+				_parse_revision_meta_section(section_data, result)
+
+		offset += 5 + section_len
+
+	return result
+
+
+## Encode a ChunkPayload into binary format.
+static func encode_binary(payload: ChunkPayload) -> PackedByteArray:
+	var sections := PackedByteArray()
+
+	# Build metadata section
+	sections.append_array(_build_metadata_section(payload))
+	# Build tile sections
+	for layer in payload.tile_layers:
+		sections.append_array(_build_tile_section(layer))
+	# Build object sections
+	for obj in payload.objects:
+		sections.append_array(_build_object_section(obj))
+	# Build flags section
+	sections.append_array(_build_flags_section(payload.flags))
+	# Build revision meta section
+	sections.append_array(_build_revision_meta_section(payload))
+
+	var payload_bytes := PackedByteArray(sections)
+	var checksum := _sha256_hex(payload_bytes)
+
+	# Build header
+	var header := PackedByteArray()
+	header.append_array(MAGIC)
+	header.append_array(_write_uint16(1))  # version
+	header.append_array(_write_uint16(0))  # header_len (after this field)
+	header.append_array(_write_uint32(0))  # flags
+	header.append_array(_write_uint32(payload_bytes.size()))
+	header.append_array(_hex_to_bytes(checksum))
+
+	return header + payload_bytes
+
+
+# ─── Section Parsers ────────────────────────────────────────────────────────
+
+static func _parse_metadata_section(data: PackedByteArray, result: ChunkPayload) -> void:
+	var offset := 0
+
+	# world_id (length-prefixed string)
+	var world_id_len := _read_uint16(data, offset)
+	offset += 2
+	result.world_id = data.slice(offset, offset + world_id_len).get_string_from_utf8()
+	offset += world_id_len
+
+	# room_id (length-prefixed string)
+	var room_id_len := _read_uint16(data, offset)
+	offset += 2
+	result.room_id = data.slice(offset, offset + room_id_len).get_string_from_utf8()
+	offset += room_id_len
+
+	# coord (3 × int32)
+	result.coord = Vector3i(
+		_read_int32(data, offset),
+		_read_int32(data, offset + 4),
+		_read_int32(data, offset + 8)
+	)
+	offset += 12
+
+	# bounds (6 × float32)
+	var min_pos := Vector3(
+		_read_float32(data, offset),
+		_read_float32(data, offset + 4),
+		_read_float32(data, offset + 8)
+	)
+	var max_pos := Vector3(
+		_read_float32(data, offset + 12),
+		_read_float32(data, offset + 16),
+		_read_float32(data, offset + 20)
+	)
+	result.bounds = AABB(min_pos, max_pos - min_pos)
+
+
+static func _parse_tile_section(data: PackedByteArray, result: ChunkPayload) -> void:
+	var layer := TileLayerData.new()
+	var offset := 0
+
+	# name (length-prefixed string)
+	var name_len := _read_uint16(data, offset)
+	offset += 2
+	layer.name = data.slice(offset, offset + name_len).get_string_from_utf8()
+	offset += name_len
+
+	# layer_id (uint16)
+	layer.layer_id = _read_uint16(data, offset)
+	offset += 2
+
+	# dimensions (3 × uint16)
+	layer.width = _read_uint16(data, offset)
+	offset += 2
+	layer.height = _read_uint16(data, offset)
+	offset += 2
+	layer.depth = _read_uint16(data, offset)
+	offset += 2
+
+	# palette
+	var palette_count := _read_uint16(data, offset)
+	offset += 2
+	for _i in range(palette_count):
+		var tile_def := TileDef.new()
+		tile_def.id = _read_uint16(data, offset)
+		offset += 2
+
+		var asset_id_len := _read_uint16(data, offset)
+		offset += 2
+		tile_def.asset_id = data.slice(offset, offset + asset_id_len).get_string_from_utf8()
+		offset += asset_id_len
+
+		tile_def.solid = data[offset] != 0
+		offset += 1
+
+		tile_def.flags = _read_uint32(data, offset)
+		offset += 4
+
+		tile_def.variants = data[offset]
+		offset += 1
+
+		layer.palette.append(tile_def)
+
+	# tiles
+	var tile_count := _read_uint32(data, offset)
+	offset += 4
+	for i in range(tile_count):
+		layer.tiles.append(_read_uint16(data, offset))
+		offset += 2
+
+	result.tile_layers.append(layer)
+
+
+static func _parse_object_section(data: PackedByteArray, result: ChunkPayload) -> void:
+	var obj := WorldObjectData.new()
+	var offset := 0
+
+	# id (length-prefixed string)
+	var id_len := _read_uint16(data, offset)
+	offset += 2
+	obj.id = data.slice(offset, offset + id_len).get_string_from_utf8()
+	offset += id_len
+
+	# type (length-prefixed string)
+	var type_len := _read_uint16(data, offset)
+	offset += 2
+	obj.type = data.slice(offset, offset + type_len).get_string_from_utf8()
+	offset += type_len
+
+	# asset_id (length-prefixed string)
+	var asset_id_len := _read_uint16(data, offset)
+	offset += 2
+	obj.asset_id = data.slice(offset, offset + asset_id_len).get_string_from_utf8()
+	offset += asset_id_len
+
+	# position (3 × float32)
+	obj.position = Vector3(
+		_read_float32(data, offset),
+		_read_float32(data, offset + 4),
+		_read_float32(data, offset + 8)
+	)
+	offset += 12
+
+	# rotation (4 × float32)
+	obj.rotation = Vector4(
+		_read_float32(data, offset),
+		_read_float32(data, offset + 4),
+		_read_float32(data, offset + 8),
+		_read_float32(data, offset + 12)
+	)
+	offset += 16
+
+	# scale (3 × float32)
+	obj.scale = Vector3(
+		_read_float32(data, offset),
+		_read_float32(data, offset + 4),
+		_read_float32(data, offset + 8)
+	)
+	offset += 12
+
+	# dynamic (uint8)
+	obj.dynamic = data[offset] != 0
+	offset += 1
+
+	# properties (length-prefixed JSON string)
+	var props_len := _read_uint16(data, offset)
+	offset += 2
+	var props_str := data.slice(offset, offset + props_len).get_string_from_utf8()
+	offset += props_len
+	obj.properties = JSON.parse_string(props_str) or {}
+
+	# flags (ContentFlags)
+	obj.flags.violence = data[offset]
+	offset += 1
+	obj.flags.sexual = data[offset]
+	offset += 1
+	obj.flags.language = data[offset]
+	offset += 1
+	obj.flags.substance = data[offset]
+	offset += 1
+	obj.flags.gambling = data[offset]
+	offset += 1
+	obj.flags.horror = data[offset]
+	offset += 1
+	obj.flags.hate = data[offset]
+	offset += 1
+	obj.flags.custom = data[offset]
+	offset += 1
+	obj.flags.mature = data[offset] != 0
+	offset += 1
+
+	var source_count := _read_uint16(data, offset)
+	offset += 2
+	for _i in range(source_count):
+		var src_len := _read_uint16(data, offset)
+		offset += 2
+		obj.flags.sources.append(data.slice(offset, offset + src_len).get_string_from_utf8())
+		offset += src_len
+
+	result.objects.append(obj)
+
+
+static func _parse_flags_section(data: PackedByteArray, flags: ContentFlags) -> void:
+	flags.violence = data[0]
+	flags.sexual = data[1]
+	flags.language = data[2]
+	flags.substance = data[3]
+	flags.gambling = data[4]
+	flags.horror = data[5]
+	flags.hate = data[6]
+	flags.custom = data[7]
+	flags.mature = data[8] != 0
+
+	var offset := 9
+	var source_count := _read_uint16(data, offset)
+	offset += 2
+	for _i in range(source_count):
+		var src_len := _read_uint16(data, offset)
+		offset += 2
+		flags.sources.append(data.slice(offset, offset + src_len).get_string_from_utf8())
+		offset += src_len
+
+
+static func _parse_revision_meta_section(data: PackedByteArray, result: ChunkPayload) -> void:
+	var offset := 0
+	# created_at (int64 unix)
+	result.created_at = _read_int64(data, offset)
+	offset += 8
+	# updated_at (int64 unix)
+	result.updated_at = _read_int64(data, offset)
+	offset += 8
+	# revision (uint32)
+	result.revision = _read_uint32(data, offset)
+	offset += 4
+	# author (length-prefixed string)
+	var author_len := _read_uint16(data, offset)
+	offset += 2
+	result.author = data.slice(offset, offset + author_len).get_string_from_utf8()
+
+
+# ─── Section Builders ───────────────────────────────────────────────────────
+
+static func _build_metadata_section(payload: ChunkPayload) -> PackedByteArray:
+	var data := PackedByteArray()
+	data.append_array(_write_string(payload.world_id))
+	data.append_array(_write_string(payload.room_id))
+	data.append_array(_write_int32(payload.coord.x))
+	data.append_array(_write_int32(payload.coord.y))
+	data.append_array(_write_int32(payload.coord.z))
+	data.append_array(_write_float32(payload.bounds.position.x))
+	data.append_array(_write_float32(payload.bounds.position.y))
+	data.append_array(_write_float32(payload.bounds.position.z))
+	data.append_array(_write_float32(payload.bounds.size.x))
+	data.append_array(_write_float32(payload.bounds.size.y))
+	data.append_array(_write_float32(payload.bounds.size.z))
+	return data
+
+
+static func _build_tile_section(layer: TileLayerData) -> PackedByteArray:
+	var data := PackedByteArray()
+	data.append_array(_write_string(layer.name))
+	data.append_array(_write_uint16(layer.layer_id))
+	data.append_array(_write_uint16(layer.width))
+	data.append_array(_write_uint16(layer.height))
+	data.append_array(_write_uint16(layer.depth))
+	data.append_array(_write_uint16(layer.palette.size()))
+
+	for tile_def in layer.palette:
+		data.append_array(_write_uint16(tile_def.id))
+		data.append_array(_write_string(tile_def.asset_id))
+		data.append(tile_def.solid as int)
+		data.append_array(_write_uint32(tile_def.flags))
+		data.append(tile_def.variants)
+
+	data.append_array(_write_uint32(layer.tiles.size()))
+	for tile_id in layer.tiles:
+		data.append_array(_write_uint16(tile_id))
+
+	return _wrap_section(data, SECTION_TILE)
+
+
+static func _build_object_section(obj: WorldObjectData) -> PackedByteArray:
+	var data := PackedByteArray()
+	data.append_array(_write_string(obj.id))
+	data.append_array(_write_string(obj.type))
+	data.append_array(_write_string(obj.asset_id))
+	data.append_array(_write_float32(obj.position.x))
+	data.append_array(_write_float32(obj.position.y))
+	data.append_array(_write_float32(obj.position.z))
+	data.append_array(_write_float32(obj.rotation.x))
+	data.append_array(_write_float32(obj.rotation.y))
+	data.append_array(_write_float32(obj.rotation.z))
+	data.append_array(_write_float32(obj.rotation.w))
+	data.append_array(_write_float32(obj.scale.x))
+	data.append_array(_write_float32(obj.scale.y))
+	data.append_array(_write_float32(obj.scale.z))
+	data.append(obj.dynamic as int)
+
+	var props_json := JSON.stringify(obj.properties, "  ")
+	data.append_array(_write_string(props_json))
+
+	data.append(obj.flags.violence)
+	data.append(obj.flags.sexual)
+	data.append(obj.flags.language)
+	data.append(obj.flags.substance)
+	data.append(obj.flags.gambling)
+	data.append(obj.flags.horror)
+	data.append(obj.flags.hate)
+	data.append(obj.flags.custom)
+	data.append(obj.flags.mature as int)
+	data.append_array(_write_uint16(obj.flags.sources.size()))
+	for src in obj.flags.sources:
+		data.append_array(_write_string(src))
+
+	return _wrap_section(data, SECTION_OBJECT)
+
+
+static func _build_flags_section(flags: ContentFlags) -> PackedByteArray:
+	var data := PackedByteArray()
+	data.append(flags.violence)
+	data.append(flags.sexual)
+	data.append(flags.language)
+	data.append(flags.substance)
+	data.append(flags.gambling)
+	data.append(flags.horror)
+	data.append(flags.hate)
+	data.append(flags.custom)
+	data.append(flags.mature as int)
+	data.append_array(_write_uint16(flags.sources.size()))
+	for src in flags.sources:
+		data.append_array(_write_string(src))
+	return _wrap_section(data, SECTION_FLAGS)
+
+
+static func _build_revision_meta_section(payload: ChunkPayload) -> PackedByteArray:
+	var data := PackedByteArray()
+	data.append_array(_write_int64(payload.created_at))
+	data.append_array(_write_int64(payload.updated_at))
+	data.append_array(_write_uint32(payload.revision))
+	data.append_array(_write_string(payload.author))
+	return _wrap_section(data, SECTION_REVISION_META)
+
+
+static func _wrap_section(data: PackedByteArray, section_id: int) -> PackedByteArray:
+	var wrapped := PackedByteArray()
+	wrapped.append(section_id)
+	wrapped.append_array(_write_uint32(data.size()))
+	wrapped.append_array(data)
+	return wrapped
+
+
+# ─── Binary Helpers ─────────────────────────────────────────────────────────
+
+static func _read_uint16(data: PackedByteArray, offset: int) -> int:
+	return data[offset] | (data[offset + 1] << 8)
+
+static func _read_uint32(data: PackedByteArray, offset: int) -> int:
+	return (data[offset] | (data[offset + 1] << 8) |
+	        (data[offset + 2] << 16) | (data[offset + 3] << 24))
+
+static func _read_int32(data: PackedByteArray, offset: int) -> int:
+	var val := _read_uint32(data, offset)
+	if val >= 0x80000000:
+		return val - 0x100000000
+	return val
+
+static func _read_int64(data: PackedByteArray, offset: int) -> int:
+	var lo := _read_uint32(data, offset)
+	var hi := _read_uint32(data, offset + 4)
+	return hi * 0x100000000 + lo
+
+static func _read_float32(data: PackedByteArray, offset: int) -> float:
+	var bits := _read_uint32(data, offset)
+	return bits as float  # GDScript float is 64-bit; bits repr works for IEEE 754
+
+static func _read_hex_string(data: PackedByteArray, offset: int, length: int) -> String:
+	var hex_chars := "0123456789abcdef"
+	var result := ""
+	for i in range(length):
+		var byte_val := data[offset + i]
+		result += hex_chars[byte_val >> 4]
+		result += hex_chars[byte_val & 0x0F]
+	return result
+
+
+static func _write_uint16(val: int) -> PackedByteArray:
+	return PackedByteArray([(val & 0xFF), (val >> 8) & 0xFF])
+
+static func _write_uint32(val: int) -> PackedByteArray:
+	return PackedByteArray([
+		val & 0xFF, (val >> 8) & 0xFF, (val >> 16) & 0xFF, (val >> 24) & 0xFF
+	])
+
+static func _write_int32(val: int) -> PackedByteArray:
+	return _write_uint32(val)
+
+static func _write_int64(val: int) -> PackedByteArray:
+	var lo := val & 0xFFFFFFFF
+	var hi := (val >> 32) & 0xFFFFFFFF
+	return _write_uint32(lo) + _write_uint32(hi)
+
+static func _write_float32(val: float) -> PackedByteArray:
+	var bits := val as int
+	return _write_uint32(bits)
+
+static func _write_string(s: String) -> PackedByteArray:
+	var bytes := s.to_utf8_buffer()
+	return _write_uint16(bytes.size()) + bytes
+
+static func _hex_to_bytes(hex_str: String) -> PackedByteArray:
+	var result := PackedByteArray()
+	for i in range(0, hex_str.length(), 2):
+		var byte_val := int("0x" + hex_str.substr(i, 2), 16)
+		result.append(byte_val)
+	return result
+
+
+# ─── SHA-256 ────────────────────────────────────────────────────────────────
+
+static func _sha256_hex(data: PackedByteArray) -> String:
+	var sha256 := SHA256Hash.new()
+	sha256.start()
+	sha256.update(data)
+	var hash := sha256.finish()
+	var hex_chars := "0123456789abcdef"
+	var result := ""
+	for byte_val in hash:
+		result += hex_chars[(byte_val >> 4) & 0x0F]
+		result += hex_chars[byte_val & 0x0F]
+	return result

scripts/chunk_data_decoder.gd.uid

@@ -0,0 +1 @@
+uid://bv445xrd6f5tk

scripts/chunk_scene.gd

@@ -0,0 +1,170 @@
+class_name ChunkScene
+extends Node3D
+## A visual representation of a single loaded world chunk.
+##
+## This node is instantiated by [ChunkStreamManager] when a chunk is loaded.
+## It holds the tile layers, world objects, and metadata for one chunk of the
+## world. The scene is responsible for rendering the chunk's visual content
+## and exposing its gameplay objects to the rest of the game.
+##
+## ## Structure
+##
+## ```
+## ChunkScene (Node3D)
+##  ├── TileLayer (Node3D)  # one per tile layer (ground, walls, decor, ...)
+##  ├── StaticObject (Node3D)  # props, geometry, interactables
+##  └── DynamicObject (Node3D)  # spawnable entities (templates)
+## ```
+##
+## ## Lifecycle
+##
+## 1. [ChunkStreamManager] requests chunk data from the server.
+## 2. Server responds with binary payload.
+## 3. [ChunkStreamManager] decodes the payload and creates a [ChunkScene].
+## 4. [ChunkScene] populates itself with tile layers and objects.
+## 5. When the player moves out of range, [ChunkStreamManager] calls
+##    [method ChunkScene.queue_free] to unload it.
+
+## The chunk coordinate this scene represents.
+var coord: Vector3i = Vector3i.ZERO
+
+## The canonical chunk key.
+var key: String = ""
+
+## World-space bounding box of this chunk.
+var bounds: AABB = AABB()
+
+## Format version of the chunk data.
+var format_version: int = 1
+
+## Revision counter from the server.
+var revision: int = 0
+
+## List of tile layers in this chunk.
+var tile_layers: Array[TileLayer] = []
+
+## List of world objects (static + dynamic) in this chunk.
+var world_objects: Array[WorldObject] = []
+
+## Content moderation flags for this chunk.
+var content_flags: ChunkDataDecoder.ContentFlags = ChunkDataDecoder.ContentFlags.new()
+
+## Whether this chunk has been modified locally (not yet synced to server).
+var is_dirty: bool = false
+
+
+func _ready() -> void:
+	# Position this chunk scene at its world-space origin
+	global_position = bounds.position
+	# Set up collision shape for the chunk bounds
+	_setup_collision()
+
+
+func _setup_collision() -> void:
+	# Add a collision shape for the chunk's bounding box
+	var collision := CollisionShape3D.new()
+	var shape := BoxShape3D.new()
+	shape.size = bounds.size
+	collision.shape = shape
+	collision.name = "ChunkBounds"
+	add_child(collision)
+
+
+## Add a tile layer to this chunk scene.
+func add_tile_layer(layer: TileLayer) -> void:
+	tile_layers.append(layer)
+	var layer_node := TileLayerNode.new()
+	layer_node.tile_layer = layer
+	layer_node.chunk_coord = coord
+	add_child(layer_node)
+
+
+## Add a world object to this chunk scene.
+func add_object(obj: WorldObject) -> void:
+	world_objects.append(obj)
+	if obj.is_dynamic:
+		_add_dynamic_object(obj)
+	else:
+		_add_static_object(obj)
+
+
+func _add_static_object(obj: WorldObject) -> void:
+	var static_obj := StaticObjectNode.new()
+	static_obj.world_object = obj
+	static_obj.position = obj.position
+	static_obj.rotation = obj.rotation
+	static_obj.scale = obj.scale
+	static_obj.name = "static_%s" % obj.id
+	add_child(static_obj)
+
+
+func _add_dynamic_object(obj: WorldObject) -> void:
+	var dynamic_obj := DynamicObjectNode.new()
+	dynamic_obj.world_object = obj
+	dynamic_obj.position = obj.position
+	dynamic_obj.rotation = obj.rotation
+	dynamic_obj.scale = obj.scale
+	dynamic_obj.name = "dynamic_%s" % obj.id
+	add_child(dynamic_obj)
+
+
+## Get a world object by its ID.
+func get_object_by_id(object_id: String) -> WorldObject:
+	for obj in world_objects:
+		if obj.id == object_id:
+			return obj
+	return null
+
+
+## Get all static objects in this chunk.
+func get_static_objects() -> Array[WorldObject]:
+	var result: Array[WorldObject] = []
+	for obj in world_objects:
+		if not obj.is_dynamic:
+			result.append(obj)
+	return result
+
+
+## Get all dynamic object templates in this chunk.
+func get_dynamic_templates() -> Array[WorldObject]:
+	var result: Array[WorldObject] = []
+	for obj in world_objects:
+		if obj.is_dynamic:
+			result.append(obj)
+	return result
+
+
+## Mark this chunk as dirty (locally modified).
+func mark_dirty() -> void:
+	is_dirty = true
+
+
+## Clear all objects and tile layers from this chunk.
+func clear() -> void:
+	for child in get_children():
+		if child is TileLayerNode or child is StaticObjectNode or child is DynamicObjectNode:
+			child.queue_free()
+	tile_layers.clear()
+	world_objects.clear()
+
+
+## Get the world-space position of a tile within this chunk.
+func get_tile_world_position(tile_x: int, tile_y: int, tile_z: int = 0) -> Vector3:
+	return bounds.position + Vector3(
+		tile_x * 1.0,  # Tile size is 1 world unit
+		tile_y * 1.0,
+		tile_z * 1.0
+	)
+
+
+## Check if a world-space position is within this chunk's bounds.
+func contains_position(pos: Vector3) -> bool:
+	return bounds.has_point(pos)
+
+
+## Check if a chunk coordinate is adjacent to this chunk.
+func is_adjacent(other_coord: Vector3i) -> bool:
+	var dx := abs(coord.x - other_coord.x)
+	var dy := abs(coord.y - other_coord.y)
+	var dz := abs(coord.z - other_coord.z)
+	return dx <= 1 and dy <= 1 and dz <= 1 and (dx + dy + dz) > 0

scripts/chunk_scene.gd.uid

@@ -0,0 +1 @@
+uid://d4gh4h5iey6xb

scripts/chunk_stream_manager.gd

@@ -0,0 +1,358 @@
+class_name ChunkStreamManager
+extends Node
+## Manages loading and unloading of world chunks based on player position.
+##
+## This is the central orchestrator for the chunk streaming system. It monitors
+## the player's position, determines which chunks should be loaded, requests
+## chunk data from the server, instantiates ChunkScene nodes, and unloads
+## chunks that fall outside the streaming radius.
+##
+## ## Design
+##
+## - **Streaming radius** defines how many chunks around the player are kept
+##   loaded. Chunks beyond this radius are unloaded to save memory and CPU.
+## - **Load priority** ensures chunks closer to the player are loaded first,
+##   preventing visual pop-in at the edge of the view.
+## - **Server communication** uses the RPCs defined in docs/architecture/world.md
+##   (§5.3): `request_chunk`, `chunk_data`, `chunk_invalidated`.
+##
+## ## Usage
+##
+## Add this node to your scene tree and set the `player` reference:
+## ```gdscript
+## var stream_manager: ChunkStreamManager = $ChunkStreamManager
+## stream_manager.player = $Player
+## stream_manager.streaming_radius = 4  # chunks
+## ```
+
+## Number of chunks (radius) to keep loaded around the player.
+## A radius of 2 means a 5x5 grid of chunks centered on the player.
+## Higher values increase memory usage but reduce streaming pop-in.
+@export var streaming_radius: int = 3
+
+## Maximum number of chunks to load per frame. Prevents frame spikes during
+## rapid movement or when entering a new area.
+@export var max_loads_per_frame: int = 4
+
+## Maximum number of chunks to unload per frame.
+@export var max_unloads_per_frame: int = 4
+
+## Distance (in chunks) from the streaming radius edge before a chunk is
+## considered for unloading. Prevents rapid load/unload cycling.
+@export var unload_margin: int = 1
+
+## Emitted when a chunk finishes loading.
+signal chunk_loaded(chunk_coord: Vector3i, chunk_scene: Node)
+
+## Emitted when a chunk is unloaded.
+signal chunk_unloaded(chunk_coord: Vector3i)
+
+## Emitted when a chunk fails to load (e.g., server error).
+signal chunk_load_failed(chunk_coord: Vector3i, error: String)
+
+## Emitted when the player moves far enough to require a streaming update.
+signal streaming_updated
+
+## Reference to the player node. Must be set before the manager starts.
+var player: Node3D = null
+
+## The current player chunk coordinate.
+var _player_chunk_coord: Vector3i = Vector3i.ZERO
+
+## Map of loaded chunk coordinates to their scene nodes.
+var _loaded_chunks: Dictionary = {}
+
+## Queue of chunk coordinates pending load, sorted by distance from player.
+var _load_queue: Array[Vector3i] = []
+
+## Queue of chunk coordinates pending unload.
+var _unload_queue: Array[Vector3i] = []
+
+## Whether streaming is currently active (player is set and in game).
+var is_active: bool = false
+
+## The server RPC interface for chunk data. Set by the networking layer.
+var _server_rpc: Object = null
+
+## Internal: track which chunks are currently being loaded (to avoid duplicates).
+var _loading_in_progress: Dictionary = {}
+
+## Internal: time accumulator for throttled streaming updates.
+var _update_accumulator: float = 0.0
+
+## Internal: interval between streaming updates (seconds).
+const UPDATE_INTERVAL: float = 0.1
+
+
+func _ready() -> void:
+	# Streaming is driven from _process (main thread) so we can safely
+	# manipulate the scene tree. No background thread is used.
+	set_process(true)
+
+
+func _process(delta: float) -> void:
+	if not is_active or player == null:
+		return
+
+	_update_accumulator += delta
+	if _update_accumulator < UPDATE_INTERVAL:
+		return
+	_update_accumulator = 0.0
+
+	_update_streaming()
+	_process_load_queue()
+	_process_unload_queue()
+	streaming_updated.emit()
+
+
+func _update_streaming() -> void:
+	if player == null or not is_inside_tree():
+		return
+
+	var current_coord: Vector3i = Chunk.coord_for_position(player.global_position)
+	if current_coord == _player_chunk_coord:
+		return
+
+	_player_chunk_coord = current_coord
+	_rebuild_queues()
+
+
+func _rebuild_queues() -> void:
+	var target_set: Dictionary = _compute_target_chunks()
+
+	# Determine which chunks need to be loaded
+	var to_load: Array[Vector3i] = []
+	for coord in target_set:
+		if not _loaded_chunks.has(coord) and not _loading_in_progress.has(coord):
+			to_load.append(coord)
+
+	# Sort by distance from player (closest first)
+	to_load.sort_custom(_compare_distance)
+	_load_queue = to_load
+
+	# Determine which chunks need to be unloaded
+	var to_unload: Array[Vector3i] = []
+	for coord in _loaded_chunks:
+		if not target_set.has(coord):
+			to_unload.append(coord)
+
+	to_unload.sort_custom(_compare_distance)
+	_unload_queue = to_unload
+
+
+func _compute_target_chunks() -> Dictionary:
+	"""Compute the set of chunk coordinates that should be loaded."""
+	var target: Dictionary = {}
+	var half: int = streaming_radius
+	for dx in range(-half, half + 1):
+		for dy in range(-half, half + 1):
+			for dz in range(-half, half + 1):
+				var coord: Vector3i = Vector3i(
+					_player_chunk_coord.x + dx,
+					_player_chunk_coord.y + dy,
+					_player_chunk_coord.z + dz
+				)
+				target[coord] = coord
+	return target
+
+
+func _compare_distance(a: Vector3i, b: Vector3i) -> bool:
+	"""Compare chunk coordinates by distance from player chunk."""
+	var dist_a: int = _chunk_distance_squared(_player_chunk_coord, a)
+	var dist_b: int = _chunk_distance_squared(_player_chunk_coord, b)
+	return dist_a < dist_b
+
+
+func _chunk_distance_squared(a: Vector3i, b: Vector3i) -> int:
+	var dx: int = a.x - b.x
+	var dy: int = a.y - b.y
+	var dz: int = a.z - b.z
+	return dx * dx + dy * dy + dz * dz
+
+
+func _process_load_queue() -> void:
+	var count: int = 0
+	while count < max_loads_per_frame and not _load_queue.is_empty():
+		var coord: Vector3i = _load_queue.pop_front()
+		_load_chunk(coord)
+		count += 1
+
+
+func _process_unload_queue() -> void:
+	var count: int = 0
+	while count < max_unloads_per_frame and not _unload_queue.is_empty():
+		var coord: Vector3i = _unload_queue.pop_front()
+		_unload_chunk(coord)
+		count += 1
+
+
+func _load_chunk(coord: Vector3i) -> void:
+	if _loading_in_progress.has(coord):
+		return
+
+	_loading_in_progress[coord] = true
+
+	# Request chunk data from server via RPC
+	if _server_rpc != null and _server_rpc.has_method("request_chunk"):
+		_server_rpc.request_chunk(Chunk.build_key(
+			"", "", coord
+		))
+	else:
+		# Fallback: try to load from local cache or create empty chunk
+		_instantiate_chunk_scene(coord)
+
+
+func _on_chunk_data_received(key: String, binary_data: PackedByteArray) -> void:
+	"""Called by the networking layer when chunk data arrives from server."""
+	var coord: Vector3i = _parse_coord_from_key(key)
+	if coord == null:
+		return
+
+	_loading_in_progress.erase(coord)
+
+	# Decode the binary chunk data
+	var chunk_data: ChunkDataDecoder.ChunkPayload = ChunkDataDecoder.decode_binary(binary_data)
+	if chunk_data == null:
+		chunk_load_failed.emit(coord, "Failed to decode chunk data")
+		return
+
+	# Instantiate the chunk scene with the decoded data
+	_instantiate_chunk_scene_with_data(coord, chunk_data)
+
+
+func _on_chunk_load_error(coord: Vector3i, error_msg: String) -> void:
+	"""Called when the server reports a chunk load error."""
+	_loading_in_progress.erase(coord)
+	chunk_load_failed.emit(coord, error_msg)
+
+
+func _instantiate_chunk_scene(coord: Vector3i) -> void:
+	"""Create an empty chunk scene for the given coordinate."""
+	var chunk_scene: ChunkScene = ChunkScene.new()
+	chunk_scene.coord = coord
+	chunk_scene.key = Chunk.build_key("", "", coord)
+	chunk_scene.bounds = Chunk.compute_bounds(coord)
+	_add_loaded_chunk(coord, chunk_scene)
+
+
+func _instantiate_chunk_scene_with_data(coord: Vector3i, data: ChunkDataDecoder.ChunkPayload) -> void:
+	"""Create a chunk scene populated with server data."""
+	var chunk_scene: ChunkScene = ChunkScene.new()
+	chunk_scene.coord = coord
+	chunk_scene.key = data.key
+	chunk_scene.bounds = data.bounds
+	chunk_scene.format_version = data.format_version
+	chunk_scene.revision = data.revision
+
+	# Add tiles
+	for layer in data.tile_layers:
+		var tile_layer: TileLayer = TileLayer.new()
+		tile_layer.name = layer.name
+		tile_layer.layer_id = layer.layer_id
+		tile_layer.width = layer.width
+		tile_layer.height = layer.height
+		tile_layer.depth = layer.depth
+		tile_layer.palette = layer.palette
+		tile_layer.tiles = layer.tiles
+		chunk_scene.add_tile_layer(tile_layer)
+
+	# Add objects
+	for obj_data in data.objects:
+		var world_obj: WorldObject = WorldObject.new()
+		world_obj.id = obj_data.id
+		world_obj.type = obj_data.type
+		world_obj.asset_id = obj_data.asset_id
+		world_obj.position = obj_data.position
+		world_obj.rotation = obj_data.rotation
+		world_obj.scale = obj_data.scale
+		world_obj.properties = obj_data.properties
+		world_obj.is_dynamic = obj_data.dynamic
+		world_obj.flags = obj_data.flags
+		chunk_scene.add_object(world_obj)
+
+	# Add content flags
+	chunk_scene.content_flags = data.flags
+
+	_add_loaded_chunk(coord, chunk_scene)
+
+
+func _add_loaded_chunk(coord: Vector3i, chunk_scene: Node) -> void:
+	_loaded_chunks[coord] = chunk_scene
+	add_child(chunk_scene)
+	_loading_in_progress.erase(coord)
+	chunk_loaded.emit(coord, chunk_scene)
+
+
+func _unload_chunk(coord: Vector3i) -> void:
+	if not _loaded_chunks.has(coord):
+		return
+
+	var chunk_scene: Node = _loaded_chunks[coord]
+	if is_instance_valid(chunk_scene):
+		chunk_scene.queue_free()
+
+	_loaded_chunks.erase(coord)
+	chunk_unloaded.emit(coord)
+
+
+func _on_player_position_changed() -> void:
+	"""Call this when the player position changes significantly."""
+	if player != null:
+		_update_streaming()
+
+
+func set_server_rpc(rpc_interface: Object) -> void:
+	"""Set the server RPC interface for chunk requests."""
+	_server_rpc = rpc_interface
+
+
+func get_loaded_chunk(coord: Vector3i) -> Node:
+	"""Get a loaded chunk scene by coordinate, or null if not loaded."""
+	return _loaded_chunks.get(coord, null)
+
+
+func is_chunk_loaded(coord: Vector3i) -> bool:
+	"""Check if a chunk is currently loaded."""
+	return _loaded_chunks.has(coord)
+
+
+func get_loaded_chunk_count() -> int:
+	"""Get the number of currently loaded chunks."""
+	return _loaded_chunks.size()
+
+
+func get_all_loaded_coords() -> Array[Vector3i]:
+	"""Get all currently loaded chunk coordinates."""
+	var coords: Array[Vector3i] = []
+	for key in _loaded_chunks:
+		coords.append(key)
+	return coords
+
+
+func force_reload_chunk(coord: Vector3i) -> void:
+	"""Force reload a specific chunk (e.g., after server update)."""
+	if _loaded_chunks.has(coord):
+		_unload_chunk(coord)
+	if not _loading_in_progress.has(coord):
+		_load_chunk(coord)
+
+
+func clear_all_chunks() -> void:
+	"""Unload all chunks immediately."""
+	var coords: Array[Vector3i] = get_all_loaded_coords()
+	for coord in coords:
+		_unload_chunk(coord)
+	_load_queue.clear()
+	_unload_queue.clear()
+
+
+func _parse_coord_from_key(key: String) -> Variant:
+	"""Parse chunk coordinate from a canonical chunk key."""
+	var parts: Array[String] = key.split(":")
+	if parts.size() < 5:
+		return null
+	return Vector3i(
+		int(parts[2]),
+		int(parts[3]),
+		int(parts[4])
+	)

scripts/chunk_stream_manager.gd.uid

@@ -0,0 +1 @@
+uid://8yokqwe23c23

scripts/dynamic_object_node.gd

@@ -0,0 +1,68 @@
+class_name DynamicObjectNode
+extends Node3D
+## A visual representation of a dynamic (spawnable) world object template.
+##
+## This node is instantiated by [ChunkScene] for each dynamic [WorldObject].
+## Dynamic objects are stored as *templates* in the chunk; their runtime state
+## (position, health, inventory) is managed by the entity system, not by this
+## node. This node renders the template's visual representation so the object
+## is visible in the world.
+##
+## ## Structure
+##
+## ```
+## DynamicObjectNode (Node3D)
+##  └── MeshInstance3D  # the object's visual mesh
+## ```
+
+## The world object data this node represents.
+var world_object: WorldObject = null
+
+## The loaded mesh instance (or placeholder).
+var _mesh_instance: MeshInstance3D = null
+
+
+func _ready() -> void:
+	if world_object == null:
+		return
+	_load_mesh()
+
+
+## Load and attach the object's mesh.
+func _load_mesh() -> void:
+	_mesh_instance = MeshInstance3D.new()
+	_mesh_instance.name = "mesh"
+
+	var mesh := _load_asset_mesh(world_object.asset_id)
+	if mesh == null:
+		mesh = _make_placeholder_mesh()
+
+	_mesh_instance.mesh = mesh
+	add_child(_mesh_instance)
+
+
+## Attempt to load a mesh from the asset path.
+func _load_asset_mesh(asset_id: String) -> Mesh:
+	if asset_id.is_empty():
+		return null
+	var path := "res://assets/%s" % asset_id
+	if ResourceLoader.exists(path):
+		var res := load(path)
+		if res is Mesh:
+			return res
+	return null
+
+
+## Create a simple placeholder sphere mesh when the real asset is unavailable.
+func _make_placeholder_mesh() -> Mesh:
+	var mesh := SphereMesh.new()
+	mesh.radius = 0.5
+	mesh.height = 1.0
+	return mesh
+
+
+## Get the world object's display name.
+func get_display_name() -> String:
+	if world_object == null:
+		return ""
+	return world_object.get_display_name()

scripts/dynamic_object_node.gd.uid

@@ -0,0 +1 @@
+uid://dyjqcstdnr4u1

scripts/main_menu.gd

@@ -1,14 +0,0 @@
-extends Control
-
-
-func _ready():
-	pass
-
-
-func _on_play_button_pressed():
-	# No gameplay scene exists yet — wire this to the real scene once one lands.
-	print("Play pressed — no gameplay scene yet")
-
-
-func _on_quit_button_pressed():
-	get_tree().quit()

scripts/static_object_node.gd

@@ -0,0 +1,67 @@
+class_name StaticObjectNode
+extends Node3D
+## A visual representation of a static world object within a chunk.
+##
+## This node is instantiated by [ChunkScene] for each static (non-dynamic)
+## [WorldObject]. It renders the object's mesh (referenced by `asset_id`) at
+## the object's transform. If the asset is not yet loaded, a placeholder mesh
+## is shown.
+##
+## ## Structure
+##
+## ```
+## StaticObjectNode (Node3D)
+##  └── MeshInstance3D  # the object's visual mesh
+## ```
+
+## The world object data this node represents.
+var world_object: WorldObject = null
+
+## The loaded mesh instance (or placeholder).
+var _mesh_instance: MeshInstance3D = null
+
+
+func _ready() -> void:
+	if world_object == null:
+		return
+	_load_mesh()
+
+
+## Load and attach the object's mesh.
+func _load_mesh() -> void:
+	_mesh_instance = MeshInstance3D.new()
+	_mesh_instance.name = "mesh"
+
+	# Try to load the asset by its id (path). Fall back to a placeholder.
+	var mesh := _load_asset_mesh(world_object.asset_id)
+	if mesh == null:
+		mesh = _make_placeholder_mesh()
+
+	_mesh_instance.mesh = mesh
+	add_child(_mesh_instance)
+
+
+## Attempt to load a mesh from the asset path.
+func _load_asset_mesh(asset_id: String) -> Mesh:
+	if asset_id.is_empty():
+		return null
+	var path := "res://assets/%s" % asset_id
+	if ResourceLoader.exists(path):
+		var res := load(path)
+		if res is Mesh:
+			return res
+	return null
+
+
+## Create a simple placeholder box mesh when the real asset is unavailable.
+func _make_placeholder_mesh() -> Mesh:
+	var mesh := BoxMesh.new()
+	mesh.size = Vector3(1.0, 1.0, 1.0)
+	return mesh
+
+
+## Get the world object's display name.
+func get_display_name() -> String:
+	if world_object == null:
+		return ""
+	return world_object.get_display_name()

scripts/static_object_node.gd.uid

@@ -0,0 +1 @@
+uid://chf6mruev1kc4

scripts/tile_def.gd

@@ -0,0 +1,42 @@
+class_name TileDef
+extends RefCounted
+## A single tile definition (palette entry) within a tile layer.
+##
+## Maps a tile ID to its asset reference and gameplay flags. See
+## docs/architecture/world.md §3.2.
+
+## Tile ID (index into the layer palette). 0 is reserved for empty/air.
+var id: int = 0
+
+## Reference to the tile/terrain asset.
+var asset_id: String = ""
+
+## Whether this tile has collision.
+var solid: bool = false
+
+## Bitmask flags: bit 0 = walkable, bit 1 = climbable, bit 2 = liquid.
+var flags: int = 0
+
+## Number of visual variants for this tile.
+var variants: int = 1
+
+
+func _init(p_id: int = 0, p_asset_id: String = "", p_solid: bool = false,
+		p_flags: int = 0, p_variants: int = 1) -> void:
+	id = p_id
+	asset_id = p_asset_id
+	solid = p_solid
+	flags = p_flags
+	variants = p_variants
+
+
+func is_walkable() -> bool:
+	return (flags & 0x01) != 0
+
+
+func is_climbable() -> bool:
+	return (flags & 0x02) != 0
+
+
+func is_liquid() -> bool:
+	return (flags & 0x04) != 0

scripts/tile_def.gd.uid

@@ -0,0 +1 @@
+uid://bavmpbmthilbx

scripts/tile_layer.gd

@@ -0,0 +1,83 @@
+class_name TileLayer
+extends RefCounted
+## A single tile layer within a chunk.
+##
+## Holds the dense grid of tile IDs, the palette mapping tile IDs to tile
+## definitions, and the layer metadata. This is the runtime representation of
+## the `TileLayer` from the chunk data format (see docs/architecture/world.md
+## §3.2).
+
+## Layer name (e.g. "ground", "walls", "decor").
+var name: String = ""
+
+## Numeric layer id, unique within the chunk.
+var layer_id: int = 0
+
+## Grid dimensions in tiles.
+var width: int = 0
+var height: int = 0
+var depth: int = 1
+
+## Palette mapping tile IDs to tile definitions (shared per layer).
+var palette: Array[TileDef] = []
+
+## Dense, row-major tile IDs. Length = width * height * depth.
+var tiles: PackedInt32Array = PackedInt32Array()
+
+
+func _init(
+	p_layer_name: String = "",
+	p_layer_id: int = 0,
+	p_width: int = 0,
+	p_height: int = 0,
+	p_depth: int = 1
+) -> void:
+	name = p_layer_name
+	layer_id = p_layer_id
+	width = p_width
+	height = p_height
+	depth = p_depth
+
+
+## Total number of tiles in this layer.
+func tile_count() -> int:
+	return width * height * depth
+
+
+## Get the tile ID at (x, y, z). Returns 0 (empty) for out-of-bounds.
+func get_tile(x: int, y: int, z: int = 0) -> int:
+	if x < 0 or x >= width or y < 0 or y >= height or z < 0 or z >= depth:
+		return 0
+	var idx := (z * height + y) * width + x
+	if idx < tiles.size():
+		return tiles[idx]
+	return 0
+
+
+## Set the tile ID at (x, y, z). No-op if out of bounds.
+func set_tile(x: int, y: int, z: int, tile_id: int) -> void:
+	if x < 0 or x >= width or y < 0 or y >= height or z < 0 or z >= depth:
+		return
+	var idx := (z * height + y) * width + x
+	if idx < tiles.size():
+		tiles[idx] = tile_id
+
+
+## Get the tile definition for a tile ID, or null if not in the palette.
+func get_tile_def(tile_id: int) -> TileDef:
+	for def in palette:
+		if def.id == tile_id:
+			return def
+	return null
+
+
+## Whether the tile at (x, y, z) is solid (collision).
+func is_solid(x: int, y: int, z: int = 0) -> bool:
+	var def := get_tile_def(get_tile(x, y, z))
+	return def != null and def.solid
+
+
+## Whether the tile at (x, y, z) is walkable.
+func is_walkable(x: int, y: int, z: int = 0) -> bool:
+	var def := get_tile_def(get_tile(x, y, z))
+	return def != null and def.is_walkable()

scripts/tile_layer.gd.uid

@@ -0,0 +1 @@
+uid://came2ygke3ajs

scripts/tile_layer_node.gd

@@ -0,0 +1,112 @@
+class_name TileLayerNode
+extends Node3D
+## A visual representation of a single tile layer within a chunk.
+##
+## This node is instantiated by [ChunkScene] for each tile layer in a chunk.
+## It renders the layer's tiles as instanced meshes (one per tile definition
+## in the palette) using [MultiMeshInstance3D] for efficiency.
+##
+## ## Structure
+##
+## ```
+## TileLayerNode (Node3D)
+##  └── MultiMeshInstance3D  # one per palette entry (tile definition)
+## ```
+
+## The tile layer data this node renders.
+var tile_layer: TileLayer = null
+
+## The chunk coordinate this layer belongs to (for world positioning).
+var chunk_coord: Vector3i = Vector3i.ZERO
+
+## Tile size in world units (each tile is 1x1x1).
+const TILE_SIZE: float = 1.0
+
+## Cache of MultiMeshInstance3D nodes, keyed by tile definition id.
+var _mesh_instances: Dictionary = {}
+
+
+func _ready() -> void:
+	if tile_layer == null:
+		return
+	_build_meshes()
+
+
+## Build the MultiMesh instances for each tile definition in the palette.
+func _build_meshes() -> void:
+	for tile_def in tile_layer.palette:
+		if tile_def.id == 0:
+			continue  # Tile 0 is "empty/air", no mesh needed
+		_create_mesh_for_tile(tile_def)
+
+
+func _create_mesh_for_tile(tile_def: TileDef) -> void:
+	# Count how many cells use this tile definition
+	var count := 0
+	for tile_id in tile_layer.tiles:
+		if tile_id == tile_def.id:
+			count += 1
+
+	if count == 0:
+		return
+
+	var multi_mesh := MultiMesh.new()
+	multi_mesh.transform_format = MultiMesh.TRANSFORM_3D
+	multi_mesh.mesh = _make_unit_cube_mesh()
+	multi_mesh.instance_count = count
+
+	var instance_idx := 0
+	for z in range(tile_layer.depth):
+		for y in range(tile_layer.height):
+			for x in range(tile_layer.width):
+				var tile_id := tile_layer.get_tile(x, y, z)
+				if tile_id != tile_def.id:
+					continue
+				var world_pos := _tile_to_world(x, y, z)
+				var xform := Transform3D(Basis(), world_pos)
+				multi_mesh.set_instance_transform(instance_idx, xform)
+				instance_idx += 1
+
+	var mesh_instance := MultiMeshInstance3D.new()
+	mesh_instance.multimesh = multi_mesh
+	mesh_instance.name = "tiles_%d" % tile_def.id
+	add_child(mesh_instance)
+	_mesh_instances[tile_def.id] = mesh_instance
+
+
+## Convert a tile grid coordinate to a world-space position (center of tile).
+func _tile_to_world(x: int, y: int, z: int) -> Vector3:
+	var origin := Vector3(
+		chunk_coord.x * tile_layer.width,
+		chunk_coord.y * tile_layer.height,
+		chunk_coord.z * tile_layer.depth
+	)
+	return origin + Vector3(
+		x * TILE_SIZE + TILE_SIZE * 0.5,
+		y * TILE_SIZE + TILE_SIZE * 0.5,
+		z * TILE_SIZE + TILE_SIZE * 0.5
+	)
+
+
+## Create a simple unit cube mesh for tile rendering.
+func _make_unit_cube_mesh() -> Mesh:
+	var mesh := BoxMesh.new()
+	mesh.size = Vector3(TILE_SIZE, TILE_SIZE, TILE_SIZE)
+	return mesh
+
+
+## Get the tile definition at a grid position, or null if empty.
+func get_tile_def_at(x: int, y: int, z: int = 0) -> TileDef:
+	if tile_layer == null:
+		return null
+	var tile_id := tile_layer.get_tile(x, y, z)
+	if tile_id == 0:
+		return null
+	return tile_layer.get_tile_def(tile_id)
+
+
+## Clear all rendered meshes.
+func clear() -> void:
+	for child in get_children():
+		child.queue_free()
+	_mesh_instances.clear()

scripts/tile_layer_node.gd.uid

@@ -0,0 +1 @@
+uid://d1x05tq8h43gm

scripts/world_object.gd

@@ -0,0 +1,135 @@
+class_name WorldObject
+extends RefCounted
+## A world object (static or dynamic) within a chunk.
+##
+## This is the runtime representation of a WorldObject from the chunk data
+## format (see docs/architecture/world.md §3.3). It holds the object's
+## identity, transform, properties, and moderation flags.
+
+## Stable object ID, unique within the chunk.
+var id: String = ""
+
+## Object type (e.g. "prop", "interactable", "spawn_point", "door").
+var type: String = ""
+
+## Reference to the object's mesh/glTF asset.
+var asset_id: String = ""
+
+## World-space position.
+var position: Vector3 = Vector3.ZERO
+
+## World-space rotation as a quaternion (x, y, z, w).
+var rotation: Vector4 = Vector4(0, 0, 0, 1)
+
+## World-space scale.
+var scale: Vector3 = Vector3.ONE
+
+## Type-specific key/value properties.
+var properties: Dictionary = {}
+
+## Whether this is a spawnable dynamic entity (true) or static (false).
+var is_dynamic: bool = false
+
+## Per-object content moderation flags.
+var flags: ChunkDataDecoder.ContentFlags = ChunkDataDecoder.ContentFlags.new()
+
+## Whether this object has been modified locally.
+var is_dirty: bool = false
+
+
+func _init(
+	p_id: String = "",
+	p_type: String = "",
+	p_asset_id: String = "",
+	p_position: Vector3 = Vector3.ZERO,
+	p_rotation: Vector4 = Vector4(0, 0, 0, 1),
+	p_scale: Vector3 = Vector3.ONE,
+	p_properties: Dictionary = {},
+	p_dynamic: bool = false,
+	p_flags: ChunkDataDecoder.ContentFlags = null
+) -> void:
+	id = p_id
+	type = p_type
+	asset_id = p_asset_id
+	position = p_position
+	rotation = p_rotation
+	scale = p_scale
+	properties = p_properties
+	is_dynamic = p_dynamic
+	if p_flags != null:
+		flags = p_flags
+
+
+## Get a property value by key.
+func get_property(key: String) -> Variant:
+	return properties.get(key)
+
+
+## Set a property value.
+func set_property(key: String, value: Variant) -> void:
+	properties[key] = value
+	is_dirty = true
+
+
+## Check if this object is walkable (based on properties).
+func is_walkable() -> bool:
+	return properties.get("walkable", true)
+
+
+## Check if this object is climbable (based on properties).
+func is_climbable() -> bool:
+	return properties.get("climbable", false)
+
+
+## Check if this object is interactable.
+func is_interactable() -> bool:
+	return type == "interactable" or properties.get("interactable", false)
+
+
+## Get the object's display name.
+func get_display_name() -> String:
+	return properties.get("display_name", id)
+
+
+## Serialize this object to a dictionary (for networking).
+func to_dict() -> Dictionary:
+	return {
+		"id": id,
+		"type": type,
+		"asset_id": asset_id,
+		"position": [position.x, position.y, position.z],
+		"rotation": [rotation.x, rotation.y, rotation.z, rotation.w],
+		"scale": [scale.x, scale.y, scale.z],
+		"properties": properties,
+		"dynamic": is_dynamic,
+	}
+
+
+## Create a WorldObject from a dictionary (for networking).
+static func from_dict(d: Dictionary) -> WorldObject:
+	var pos := Vector3(
+		d.get("position", [0, 0, 0])[0],
+		d.get("position", [0, 0, 0])[1],
+		d.get("position", [0, 0, 0])[2]
+	)
+	var rot := Vector4(
+		d.get("rotation", [0, 0, 0, 1])[0],
+		d.get("rotation", [0, 0, 0, 1])[1],
+		d.get("rotation", [0, 0, 0, 1])[2],
+		d.get("rotation", [0, 0, 0, 1])[3]
+	)
+	var scl := Vector3(
+		d.get("scale", [1, 1, 1])[0],
+		d.get("scale", [1, 1, 1])[1],
+		d.get("scale", [1, 1, 1])[2]
+	)
+	return WorldObject.new(
+		d.get("id", ""),
+		d.get("type", ""),
+		d.get("asset_id", ""),
+		pos,
+		rot,
+		scl,
+		d.get("properties", {}),
+		d.get("dynamic", false),
+	)

scripts/world_object.gd.uid

@@ -0,0 +1 @@
+uid://cxut2ghbsvobn