feat: add profiling

src/systems/profiling.rs

@@ -0,0 +1,32 @@
+use bevy_ecs::prelude::Resource;
+use bevy_ecs::system::{IntoSystem, System};
+use parking_lot::Mutex;
+use std::collections::HashMap;
+use std::time::Duration;
+
+#[derive(Resource, Default, Debug)]
+pub struct SystemTimings {
+    pub timings: Mutex<HashMap<&'static str, Duration>>,
+}
+
+pub fn profile<S, M>(name: &'static str, system: S) -> impl FnMut(&mut bevy_ecs::world::World)
+where
+    S: IntoSystem<(), (), M> + 'static,
+{
+    let mut system: S::System = IntoSystem::into_system(system);
+    let mut is_initialized = false;
+    move |world: &mut bevy_ecs::world::World| {
+        if !is_initialized {
+            system.initialize(world);
+            is_initialized = true;
+        }
+
+        let start = std::time::Instant::now();
+        system.run((), world);
+        let duration = start.elapsed();
+
+        if let Some(mut timings) = world.get_resource_mut::<SystemTimings>() {
+            timings.timings.lock().insert(name, duration);
+        }
+    }
+}