send the initial state to clients

kennel/config.py

@@ -5,8 +5,8 @@ load_dotenv()
 
 
 class Config:
-    SIMULATION_WIDTH = int(os.getenv("SIMULATION_WIDTH", 1000))
-    SIMULATION_HEIGHT = int(os.getenv("SIMULATION_HEIGHT", 1000))
+    WORLD_WIDTH = int(os.getenv("WORLD_WIDTH", 1000))
+    WORLD_HEIGHT = int(os.getenv("WORLD_HEIGHT", 1000))
 
     HATECOMPUTERS_ENDPOINT = os.getenv(
         "HATECOMPUTERS_ENDPOINT", "https://hatecomputers.club"

kennel/engine/components/controllable.py

@@ -10,4 +10,5 @@ class Controllable(Component):
         return f"Controllable(by={self.by})"
 
     def dict(self) -> dict:
-        return {"by": self.by}
+        # don't serialize who owns this
+        return {}

kennel/engine/entities/entity.py

@@ -23,6 +23,13 @@ class Entity:
     def add_component(self, component: Component) -> None:
         self.components[component.component_type] = component
 
+    def to_dict(self) -> dict:
+        return {
+            "entity_type": self.entity_type,
+            "id": self.id,
+            "components": {k: v.dict() for k, v in self.components.items()},
+        }
+
 
 class EntityManager:
     def __init__(self):
@@ -58,3 +65,6 @@ class EntityManager:
 
     def get_entity(self, entity_id: str) -> Optional[Entity]:
         return self.entities.get(entity_id)
+
+    def to_dict(self) -> dict:
+        return {k: v.to_dict() for k, v in self.entities.items()}

kennel/engine/systems/network.py

@@ -6,6 +6,7 @@ import asyncio
 
 
 class EventType(str, Enum):
+    INITIAL_STATE = "INITIAL_STATE"
     ENTITY_BORN = "ENTITY_BORN"
     ENTITY_POSITION_UPDATE = "ENTITY_POSITION_UPDATE"
     ENTITY_DEATH = "ENTITY_DEATH"

kennel/engine/systems/system.py

@@ -5,6 +5,7 @@ from abc import abstractmethod
 
 class SystemType(str, Enum):
     NETWORK = "NETWORK"
+    WORLD = "WORLD"
 
 
 class System:

kennel/engine/systems/world.py

@@ -0,0 +1,24 @@
+from kennel.engine.systems.system import System, SystemType
+from kennel.engine.entities.entity import EntityManager
+from kennel.engine.components.component import ComponentType
+from kennel.app import logger
+
+
+class WorldSystem(System):
+    def __init__(self, width: int, height: int):
+        super().__init__(SystemType.WORLD)
+        self.width = width
+        self.height = height
+
+    async def update(self, entity_manager: EntityManager, delta_time: float):
+        entities = entity_manager.get_entities_with_component(ComponentType.POSITION)
+        for entity in entities:
+            position = entity.get_component(ComponentType.POSITION)
+            if position is None:
+                logger.error(f"Entity {entity} has no position component")
+                continue
+
+            position.x = max(0, min(self.width, position.x))
+            position.y = max(0, min(self.height, position.y))
+
+            entity.add_component(position)

kennel/kennel.py

@@ -10,6 +10,7 @@ from kennel.engine.systems.network import (
     Event,
     EventType,
 )
+from kennel.engine.systems.world import WorldSystem
 from kennel.config import config
 from .app import logger
 from typing import List
@@ -59,9 +60,6 @@ class KennelClientEventTransformer(ClientEventTransformer):
                 logger.error(f"Entity {id} does not exist")
                 return event
             for component_type in entity.components:
-                if component_type == ComponentType.CONTROLLABLE:
-                    # Do not send controllable components to clients
-                    continue
                 component = entity.get_component(component_type)
                 if component is not None:
                     event.data[component_type] = component.dict()
@@ -69,8 +67,9 @@ class KennelClientEventTransformer(ClientEventTransformer):
         return event
 
 
+system_manager.add_system(WorldSystem(config.WORLD_WIDTH, config.WORLD_HEIGHT))
 system_manager.add_system(
-    NetworkSystem(EventProcessor(), KennelClientEventTransformer())
+    NetworkSystem(EventProcessor(), KennelClientEventTransformer()),
 )
 
 kennel = Game(entity_manager, system_manager, config.MIN_TIME_STEP)

kennel/main.py

@@ -12,16 +12,16 @@ from fastapi.staticfiles import StaticFiles
 from kennel.engine.systems.system import SystemType
 from kennel.engine.systems.network import Event, Publishable, EventType
 from typing import Annotated, Optional
-from .kennel import (
+from kennel.kennel import (
     kennel,
     system_manager,
     entity_manager,
     create_session_controllable_entities,
 )
-from .app import app, templates, logger
-from .kennelcats import KennelCatService
-from .middleware import logger_middleware
-from .config import config
+from kennel.app import app, templates, logger
+from kennel.kennelcats import KennelCatService
+from kennel.middleware import logger_middleware
+from kennel.config import config
 import asyncio
 import uuid
 
@@ -83,8 +83,19 @@ async def websocket_endpoint(
     session: Annotated[str, Depends(get_cookie_or_token)],
 ):
     await websocket.accept()
-    session_entities = create_session_controllable_entities(session)
     logger.info(f"Websocket connection established for session {session}")
+
+    await websocket.send_json(
+        {
+            "event_type": EventType.INITIAL_STATE,
+            "data": {
+                "world": {"width": config.WORLD_WIDTH, "height": config.WORLD_HEIGHT},
+                "entities": kennel.entity_manager.to_dict(),
+            },
+        }
+    )
+
+    session_entities = create_session_controllable_entities(session)
     try:
         network_system = system_manager.get_system(SystemType.NETWORK)
         if network_system is None:
@@ -97,9 +108,8 @@ async def websocket_endpoint(
 
         network_system.add_client(session, WebSocketClient(websocket))
         while True:
-            network_system.client_event(
-                session, Event.from_dict(await websocket.receive_json())
-            )
+            message = await websocket.receive_json()
+            network_system.client_event(session, Event.from_dict(message))
     except Exception as e:
         logger.error(f"WebSocket exception {e}")
     finally:

templates/index.html

@@ -5,10 +5,10 @@
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <meta http-equiv="X-UA-Compatible" content="ie=edge">
     <title>Kennel Club</title>
+    <script src='https://unpkg.com/panzoom@9.4.0/dist/panzoom.min.js'></script>
   </head>
   <body>
     <div id="kennel-window"></div>
     <script src="{{ url_for('static', path='/index.js') }}"></script>
   </body>
 </html>
-