bevy/crates/bevy_ecs/examples/component_storage.rs
Carter Anderson 11b41206eb Add upstream bevy_ecs and prepare for custom-shaders merge (#2815)
This updates the `pipelined-rendering` branch to use the latest `bevy_ecs` from `main`. This accomplishes a couple of goals:

1. prepares for upcoming `custom-shaders` branch changes, which were what drove many of the recent bevy_ecs changes on `main`
2. prepares for the soon-to-happen merge of `pipelined-rendering` into `main`. By including bevy_ecs changes now, we make that merge simpler / easier to review. 

I split this up into 3 commits:

1. **add upstream bevy_ecs**: please don't bother reviewing this content. it has already received thorough review on `main` and is a literal copy/paste of the relevant folders (the old folders were deleted so the directories are literally exactly the same as `main`).
2. **support manual buffer application in stages**: this is used to enable the Extract step. we've already reviewed this once on the `pipelined-rendering` branch, but its worth looking at one more time in the new context of (1).
3. **support manual archetype updates in QueryState**: same situation as (2).
2021-09-14 06:14:19 +00:00

39 lines
1.4 KiB
Rust

use bevy_ecs::{
component::{ComponentDescriptor, StorageType},
prelude::*,
};
// This example shows how to configure the storage of Components.
// A system demonstrates that querying for components is independent of their storage type.
fn main() {
let mut world = World::new();
// Store components of type `i32` in a Sparse set
world
.register_component(ComponentDescriptor::new::<i32>(StorageType::SparseSet))
.expect("The component of type i32 is already in use");
// Components of type i32 will have the above configured Sparse set storage,
// while f64 components will have the default table storage
world.spawn().insert(1).insert(0.1);
world.spawn().insert(2);
world.spawn().insert(0.2);
// Setup a schedule and stage to add a system querying for the just spawned entities
let mut schedule = Schedule::default();
let mut update = SystemStage::parallel();
update.add_system(query_entities);
schedule.add_stage("update", update);
schedule.run(&mut world);
}
// The storage type does not matter for how to query in systems
fn query_entities(entities_with_i32: Query<&i32>, entities_with_f64: Query<&f64>) {
for value in entities_with_i32.iter() {
println!("Got entity with i32: {}", value);
}
for value in entities_with_f64.iter() {
println!("Got entity with f64: {}", value);
}
}