Struct FrameHistogram 

pub struct FrameHistogram { /* private fields */ }

Rolling 120-frame timing histogram.

Stores the last 120 frame timings in a fixed-size ring buffer with zero heap allocation.

Example

use martensite_devtools::hud::{FrameHistogram, FrameTiming};

let mut hist = FrameHistogram::new();
hist.record(FrameTiming {
    layout_time_ns: 500_000,
    paint_time_ns: 300_000,
    gpu_wait_time_ns: 100_000,
    total_time_ns: 900_000,
});
assert_eq!(hist.len(), 1);
let avg = hist.average();
assert_eq!(avg.total_time_ns, 900_000);

Implementations

impl FrameHistogram

pub fn new() -> Self

Creates a new empty histogram.

Example

use martensite_devtools::hud::FrameHistogram;

let hist = FrameHistogram::new();
assert!(hist.is_empty());

pub fn record(&mut self, timing: FrameTiming)

Records a frame timing into the ring buffer.

Example

use martensite_devtools::hud::{FrameHistogram, FrameTiming};

let mut hist = FrameHistogram::new();
hist.record(FrameTiming { total_time_ns: 16_000_000, ..Default::default() });
assert_eq!(hist.len(), 1);

pub fn average(&self) -> FrameTiming

Returns the average frame timing across all recorded frames.

Example

use martensite_devtools::hud::{FrameHistogram, FrameTiming};

let mut hist = FrameHistogram::new();
hist.record(FrameTiming { total_time_ns: 10_000_000, ..Default::default() });
hist.record(FrameTiming { total_time_ns: 20_000_000, ..Default::default() });
assert_eq!(hist.average().total_time_ns, 15_000_000);

pub fn percentile(&self, p: f32) -> FrameTiming

Returns the timing at the given percentile (0.0–100.0).

p=50 gives the median, p=99 gives the 99th percentile.

Example

use martensite_devtools::hud::{FrameHistogram, FrameTiming};

let mut hist = FrameHistogram::new();
for i in 1..=100 {
    hist.record(FrameTiming { total_time_ns: i * 1_000_000, ..Default::default() });
}
let p50 = hist.percentile(50.0);
assert!(p50.total_time_ns >= 49_000_000 && p50.total_time_ns <= 51_000_000);

pub fn max(&self) -> FrameTiming

Returns the maximum recorded frame timing.

Example

use martensite_devtools::hud::{FrameHistogram, FrameTiming};

let mut hist = FrameHistogram::new();
hist.record(FrameTiming { total_time_ns: 10_000_000, ..Default::default() });
hist.record(FrameTiming { total_time_ns: 30_000_000, ..Default::default() });
hist.record(FrameTiming { total_time_ns: 20_000_000, ..Default::default() });
assert_eq!(hist.max().total_time_ns, 30_000_000);

pub fn frames(&self) -> &[FrameTiming]

Returns a slice of all recorded frame timings.

Note: After the ring buffer wraps (more than 120 frames recorded), the slice is in physical storage order, not chronological order. The newest frame may appear at any position. This is suitable for aggregation (average, max, percentile) but not for chronological display.

Example

use martensite_devtools::hud::{FrameHistogram, FrameTiming};

let mut hist = FrameHistogram::new();
hist.record(FrameTiming::default());
assert_eq!(hist.frames().len(), 1);

pub fn len(&self) -> usize

Returns the number of recorded frames.

pub fn is_empty(&self) -> bool

Returns true if no frames have been recorded.

pub fn clear(&mut self)

Clears all recorded frames.

Trait Implementations

impl Clone for FrameHistogram

fn clone(&self) -> FrameHistogram

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for FrameHistogram

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

Formats the value using the given formatter.

impl Default for FrameHistogram

fn default() -> Self

Returns the “default value” for a type.