An entity component system for panda3d + additional bloat!
Sandbox tucks away some of the initial panda3d setup boiler code.
Sandbox can be installed via pip:
pip install git+https://github.com/croxis/sandbox.git
To begin using sandbox, import it and initialize with your desired log level.
import sandbox
if __name__ == '__main__':
# Configure any panda prc settings here
sandbox.init(log_level='info')
# Initiate sandbox and panda3d's game loop.
sandbox.run()sandbox.init() must be called before any entity, components, or systems can be added.
Sandbox implements an entity-component-system similar to what is described on t-machines.
To create a new entity:
import sandbox
sandbox.init()
entity = sandbox.create_entity()Components are a specific aspect of an entity to define what it is. Generally components only contain variables and no functions themselves.
import sandbox
from panda3d.core import NodePath
class PhysicsComponent:
x = 0
y = 0
z = 0
class GraphicsComponent:
node_path = None
if __name__ == '__main__':
# Configure any panda prc settings here
sandbox.init(log_level='info')
entity = sandbox.create_entity()
component = PhysicsComponent()
entity.add_component(component)
component = GraphicsComponent()
component.node_path = NodePath()
# Initiate sandbox and panda3d's game loop.
sandbox.run()Systems manipulate components. Systems run in a panda3d task that operates every frame. A system must inherit from sandbox.EntitySystem
Custom setup is done by overriding sandbox.EntitySystem.init(), NOT __init__.
There are several functions that are called by sandbox on an EntitySystem.
EntitySystem.init(): called when the system is added to the system manager EntitySystem.begin(): called once each frame before any entities are processed EntitySystem.process(entity): called for each entity being processed. If not overridden an error is thrown. EntitySystem.end(): called once each frame after all entities have been processed
An entity is passed to the process function, not the component. This allows a system to watch for multiple component, but requires for the component(s) to be manually obtained.
The component classes the system is interested in listening for are passed in the constructor.
import sandbox
from panda3d.core import NodePath
class PhysicsComponent:
x = 0
y = 0
z = 0
class GraphicsComponent:
node_path = None
class PhysicsSystem(sandbox.EntitySystem):
def init(self):
# Set up bullet world or other physics systems here
pass
def process(self, entity):
physics_component = entity.get_component(PhysicsComponent)
physics_component.x += 1
class GraphicsSystem(sandbox.EntitySystem):
def process(self, entity):
graphics_component = entity.get_component(GraphicsComponent)
physics_component = entity.get_component(PhysicsComponent)
graphics_component.node_path.set_pos(physics_component.x, physics_component.y, physics_component.z)
if __name__ == '__main__':
# Configure any panda prc settings here
sandbox.init(log_level='info')
entity = sandbox.create_entity()
component = PhysicsComponent()
entity.add_component(component)
component = GraphicsComponent()
component.node_path = NodePath()
# Set up systems and register them with the system manager
physics_system = PhysicsSystem(PhysicsComponent)
sandbox.add_system(physics_system)
graphics_system = GraphicsSystem(graphicsComponent)
sandbox.add_system(graphics_component)
# Initiate sandbox and panda3d's game loop.
sandbox.run()