Trait hecs::serialize::row::SerializeContext

pub trait SerializeContext {
    fn serialize_entity<S>(
        &mut self,
        entity: EntityRef<'_>,
        map: S
    ) -> Result<S::Ok, S::Error>
    where
        S: SerializeMap;

    fn component_count(&self, entity: EntityRef<'_>) -> Option<usize> { ... }
}

Available on crate feature row-serialize only.

Implements serialization of individual entities

Data external to the World can be exposed during serialization by storing references inside the struct implementing this trait.

Example

use hecs::{*, serialize::row::*};

#[derive(Serialize, Deserialize)]
enum ComponentId { Position, Velocity }

// Could include references to external state for use by `serialize_entity`
struct Context;

impl SerializeContext for Context {
    fn serialize_entity<S>(
        &mut self,
        entity: EntityRef<'_>,
        mut map: S,
    ) -> Result<S::Ok, S::Error>
    where
        S: serde::ser::SerializeMap,
    {
        // Call `try_serialize` for every serializable component we want to save
        try_serialize::<Position, _, _>(&entity, &ComponentId::Position, &mut map)?;
        try_serialize::<Velocity, _, _>(&entity, &ComponentId::Velocity, &mut map)?;
        // Or do something custom for more complex cases.
        map.end()
    }
}

Required Methods

fn serialize_entity<S>(
    &mut self,
    entity: EntityRef<'_>,
    map: S
) -> Result<S::Ok, S::Error>where
    S: SerializeMap,

Serialize a single entity into a map

Provided Methods

fn component_count(&self, entity: EntityRef<'_>) -> Option<usize>

Number of entries that serialize_entry will produce for entity, if known

Defaults to None. Must be overridden to return Some to support certain serializers, e.g. bincode.

Implementors