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https://github.com/bevyengine/bevy
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11b41206eb
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).
43 lines
1.1 KiB
Rust
43 lines
1.1 KiB
Rust
use bevy::{ecs::system::SystemParam, prelude::*};
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/// This example creates a SystemParam struct that counts the number of players
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fn main() {
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App::new()
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.insert_resource(PlayerCount(0))
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.add_startup_system(spawn)
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.add_system(count_players)
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.run();
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}
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pub struct Player;
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pub struct PlayerCount(usize);
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/// The SystemParam struct can contain any types that can also be included in a
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/// system function signature.
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///
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/// In this example, it includes a query and a mutable resource.
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#[derive(SystemParam)]
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struct PlayerCounter<'w, 's> {
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players: Query<'w, 's, &'static Player>,
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count: ResMut<'w, PlayerCount>,
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}
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impl<'w, 's> PlayerCounter<'w, 's> {
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fn count(&mut self) {
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self.count.0 = self.players.iter().len();
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}
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}
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/// Spawn some players to count
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fn spawn(mut commands: Commands) {
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commands.spawn().insert(Player);
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commands.spawn().insert(Player);
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commands.spawn().insert(Player);
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}
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/// The SystemParam can be used directly in a system argument.
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fn count_players(mut counter: PlayerCounter) {
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counter.count();
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println!("{} players in the game", counter.count.0);
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}
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