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use crate::engine::d2::util::Disposable;
use super::EntityID;
/// Components are bits of data and logic that can be added to entities.
#[derive(Default, Copy, Clone, Debug, PartialEq)]
pub struct Component {
/// The entity this component is attached to, or None
pub owner: Option<EntityID>,
// The owner's next component, for iteration
// pub next: Box<Option<Component>>,
// /// The component's name, generated based on its class. Components with the same name replace
// /// eachother when added to an entity.
// pub name: String,
pub flags: u32,
}
impl Component {
// Component flags
pub const STARTED: u32 = 1 << 0;
pub const NEXT_FLAG: u32 = 1 << 1; // Must be last!
}
pub trait ComponentExt {
/// Called after this component has been added to an entity.
fn on_added(&self) {}
/// Called just before this component has been removed from its entity.
fn on_removed(&self) {}
/// Called just before this component's first update after being added. This is the best place to
/// put initialization logic that requires accessing other components/entities, since it waits
/// until the rest of the entity hierarchy is accessible.
///
/// Note that on_start may be delayed until the next frame after adding a component, depending on
/// where in the update step it was added.
fn on_start(&self) {}
/// Called just before this component will be removed from its entity, if on_start was previously
/// called.
fn on_stop(&self) {}
/// Called when this component receives a game update.
/// @param dt The time elapsed since the last frame, in seconds.
fn on_update(&self, dt: f32) {}
fn name(&self) -> Option<String> {
// Subclasses will automagically implement this
None
}
}
impl ComponentExt for Component {}
impl Disposable for Component {
/// Removes this component from its owning entity.
fn dispose(&self) {
if let Some(ref owner) = self.owner {
todo!("shold get entity from storage");
// owner.remove(self);
}
}
}