Struct FrameRateMonitor 

pub struct FrameRateMonitor {
    capacity: usize,
    window: VecDeque<Duration>,
    warn_threshold: f64,
    recover_threshold: f64,
    in_warn_state: bool,
}

Sliding-window frame-rate monitor.

Constructed once per preview pipeline; observe is called every frame with the current wall-clock timestamp. The internal buffer caps at capacity to keep memory bounded.

Fields

capacity: usize

window: VecDeque<Duration>

warn_threshold: f64

recover_threshold: f64

in_warn_state: bool

true when we’ve already emitted the low-fps warning and haven’t recovered yet. Suppresses repeat warns.

Implementations

impl FrameRateMonitor

pub fn new(capacity: usize, warn_threshold: f64, recover_threshold: f64) -> Self

Build a monitor with the given window size + thresholds.

pub fn observe(&mut self, timestamp: Duration) -> Option<Transition>

Record a frame timestamp + return Some(fps) when the window crosses a threshold and the caller should emit a warn/recover log line. None for the common case where no transition happened.

pub fn current_fps(&self) -> f64

Snapshot the current sustained fps over the window.

Trait Implementations

impl Debug for FrameRateMonitor

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for FrameRateMonitor

fn default() -> Self

Returns the “default value” for a type.