feat: enhance slow frame timing warning

Cargo.lock

@@ -663,7 +663,7 @@ checksum = "42f5e15c9953c5e4ccceeb2e7382a716482c34515315f7b03532b8b4e8393d2d"
 
 [[package]]
 name = "pacman"
-version = "0.78.2"
+version = "0.78.3"
 dependencies = [
  "anyhow",
  "bevy_ecs",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "pacman"
-version = "0.78.2"
+version = "0.78.3"
 authors = ["Xevion"]
 edition = "2021"
 rust-version = "1.86.0"

src/game.rs

@@ -714,12 +714,23 @@ impl Game {
             timings.add_total_timing(total_duration, new_tick);
 
             // Log performance warnings for slow frames
-            if total_duration.as_millis() > 20 {
-                // Warn if frame takes more than 20ms
+            if total_duration.as_millis() > 17 {
+                // Warn if frame takes too long
+                let slowest_systems = timings.get_slowest_systems();
+                let systems_context = if slowest_systems.is_empty() {
+                    "No specific systems identified".to_string()
+                } else {
+                    slowest_systems
+                        .iter()
+                        .map(|(id, duration)| format!("{} ({:.2?})", id, duration))
+                        .collect::<Vec<String>>()
+                        .join(", ")
+                };
+
                 warn!(
-                    duration_ms = total_duration.as_millis(),
-                    frame_dt = ?std::time::Duration::from_secs_f32(dt),
+                    total = format!("{:.3?}", total_duration),
                     tick = new_tick,
+                    systems = systems_context,
                     "Frame took longer than expected"
                 );
             }

src/systems/profiling.rs

@@ -52,6 +52,11 @@ impl TimingBuffer {
         self.last_tick = current_tick;
     }
 
+    /// Gets the most recent timing from the buffer.
+    pub fn get_most_recent_timing(&self) -> Duration {
+        self.buffer.back().copied().unwrap_or(Duration::ZERO)
+    }
+
     /// Gets statistics for this timing buffer.
     ///
     /// # Panics
@@ -248,6 +253,61 @@ impl SystemTimings {
         // Use the formatting module to format the data
         format_timing_display(timing_data)
     }
+
+    /// Returns a list of systems with their timings, likely responsible for slow frame timings.
+    ///
+    /// First, checks if any systems took longer than 2ms on the most recent tick.
+    /// If none exceed 2ms, accumulates systems until the top 30% of total timing
+    /// is reached, stopping at 5 systems maximum.
+    ///
+    /// Returns tuples of (SystemId, Duration) in a SmallVec capped at 5 items.
+    pub fn get_slowest_systems(&self) -> SmallVec<[(SystemId, Duration); 5]> {
+        let mut system_timings: Vec<(SystemId, Duration)> = Vec::new();
+        let mut total_duration = Duration::ZERO;
+
+        // Collect most recent timing for each system (excluding Total)
+        for id in SystemId::iter() {
+            if id == SystemId::Total {
+                continue;
+            }
+
+            if let Some(buffer) = self.timings.get(&id) {
+                let recent_timing = buffer.lock().get_most_recent_timing();
+                system_timings.push((id, recent_timing));
+                total_duration += recent_timing;
+            }
+        }
+
+        // Sort by duration (highest first)
+        system_timings.sort_by(|a, b| b.1.cmp(&a.1));
+
+        // Check for systems over 2ms threshold
+        let over_threshold: SmallVec<[(SystemId, Duration); 5]> = system_timings
+            .iter()
+            .filter(|(_, duration)| duration.as_millis() >= 2)
+            .copied()
+            .collect();
+
+        if !over_threshold.is_empty() {
+            return over_threshold;
+        }
+
+        // Accumulate top systems until 30% of total is reached (max 5 systems)
+        let threshold = total_duration.as_nanos() as f64 * 0.3;
+        let mut accumulated = 0u128;
+        let mut result = SmallVec::new();
+
+        for (id, duration) in system_timings.iter().take(5) {
+            result.push((*id, *duration));
+            accumulated += duration.as_nanos();
+
+            if accumulated as f64 >= threshold {
+                break;
+            }
+        }
+
+        result
+    }
 }
 
 pub fn profile<S, M>(id: SystemId, system: S) -> impl FnMut(&mut bevy_ecs::world::World)