regecs 1.0.0

Rust Extended Generic ECS (REGECS)
Documentation
// Copyright (c) 2021, BlockProject 3D
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//! REGECS object and entity layer

use std::boxed::Box;
use std::any::Any;

use crate::event::EventContext;
use crate::event::EventResult;

/// Type alias for object references
/// 
/// *serves also as entry point into REGECS entity layer*
pub type ObjectRef = u32;

/// Low-level object interface to represent all dynamic objects managed by a scene
pub trait LowObject<TState, TComponentManager>
{
    fn on_event(&mut self, event: Box<dyn Any>, context: EventContext<TState, TComponentManager>) -> Option<EventResult>;
    fn on_init(&mut self, ptr: ObjectRef, components: &mut TComponentManager);
    fn on_remove(&mut self, ptr: ObjectRef, components: &mut TComponentManager);
}

/// High-level object interface
pub trait Object<TState, TComponentManager>
{
    type EventType: Any;

    fn event(&mut self, event: &Self::EventType, context: EventContext<TState, TComponentManager>) -> Option<EventResult>;
    fn init(&mut self, ptr: ObjectRef, components: &mut TComponentManager);
    fn remove(&mut self, ptr: ObjectRef, components: &mut TComponentManager);
}

impl <TState, TComponentManager, EventType: Any, O: Object<TState, TComponentManager, EventType = EventType>> LowObject<TState, TComponentManager> for O
{
    fn on_event(&mut self, event: Box<dyn Any>, context: EventContext<TState, TComponentManager>) -> Option<EventResult>
    {
        if let Ok(ev) = event.downcast::<EventType>()
        {
            return self.event(&ev, context);
        }
        return None;
    }

    fn on_init(&mut self, ptr: ObjectRef, components: &mut TComponentManager)
    {
        self.init(ptr, components);
    }

    fn on_remove(&mut self, ptr: ObjectRef, components: &mut TComponentManager)
    {
        self.remove(ptr, components);
    }
}