bevy_diagnostic/
frame_time_diagnostics_plugin.rs

1use crate::{Diagnostic, DiagnosticPath, Diagnostics, RegisterDiagnostic};
2use bevy_app::prelude::*;
3use bevy_core::FrameCount;
4use bevy_ecs::prelude::*;
5use bevy_time::{Real, Time};
6
7/// Adds "frame time" diagnostic to an App, specifically "frame time", "fps" and "frame count"
8///
9/// # See also
10///
11/// [`LogDiagnosticsPlugin`](crate::LogDiagnosticsPlugin) to output diagnostics to the console.
12#[derive(Default)]
13pub struct FrameTimeDiagnosticsPlugin;
14
15impl Plugin for FrameTimeDiagnosticsPlugin {
16    fn build(&self, app: &mut App) {
17        app.register_diagnostic(Diagnostic::new(Self::FRAME_TIME).with_suffix("ms"))
18            .register_diagnostic(Diagnostic::new(Self::FPS))
19            .register_diagnostic(Diagnostic::new(Self::FRAME_COUNT).with_smoothing_factor(0.0))
20            .add_systems(Update, Self::diagnostic_system);
21    }
22}
23
24impl FrameTimeDiagnosticsPlugin {
25    pub const FPS: DiagnosticPath = DiagnosticPath::const_new("fps");
26    pub const FRAME_COUNT: DiagnosticPath = DiagnosticPath::const_new("frame_count");
27    pub const FRAME_TIME: DiagnosticPath = DiagnosticPath::const_new("frame_time");
28
29    pub fn diagnostic_system(
30        mut diagnostics: Diagnostics,
31        time: Res<Time<Real>>,
32        frame_count: Res<FrameCount>,
33    ) {
34        diagnostics.add_measurement(&Self::FRAME_COUNT, || frame_count.0 as f64);
35
36        let delta_seconds = time.delta_secs_f64();
37        if delta_seconds == 0.0 {
38            return;
39        }
40
41        diagnostics.add_measurement(&Self::FRAME_TIME, || delta_seconds * 1000.0);
42
43        diagnostics.add_measurement(&Self::FPS, || 1.0 / delta_seconds);
44    }
45}
bevy_diagnostic/frame_time_diagnostics_plugin.rs

bevy_diagnostic/
frame_time_diagnostics_plugin.rs
