Struct GpuPasses 

pub struct GpuPasses {
    pub prepass: Duration,
    pub main: Duration,
    pub composite: Duration,
    pub blit: Duration,
}

One frame’s real GPU time, split by the spans the frust-owned render engine names — the counterpart of the CPU spans in FramePasses, measured on the GPU’s own clock rather than inferred from CPU wall time around a submit.

Produced only in a build whose device asked for GPU timestamps; every other frame carries None and reports gpu_q=0. A span may legitimately read zero — a frame with no off-screen layer does no composite work — so a zero is a measurement, not a gap.

Fields

prepass: Duration

Work recorded ahead of the frame’s own passes (the glyph-atlas replay).

main: Duration

The frame’s own surface passes: clear, opaque strips, alpha strips, and the hole punch.

composite: Duration

Off-screen layer pages and filter passes.

blit: Duration

The present-side conversion or blit into the swapchain.

Implementations

impl GpuPasses

pub fn main_is_measured(&self) -> bool

Whether the main span carries a real measurement.

Every submitted frame records its opening surface pass into main, and a measured timestamp pair is strictly increasing, so a measured main is never exactly Duration::ZERO. A zero here therefore means the pair was never resolved (a clear-only opening pass that drew nothing has no valid pair on Metal), not that the pass took no time. The other three spans may legitimately be zero (a frame with no off-screen layer does no composite work), so only main can be judged this way.

pub fn total(&self) -> Duration

The sum of the four spans — the frame’s attributed GPU pass time.

Queue and driver gaps between passes belong to no pass and are not folded in, so this is a lower bound on the frame’s whole GPU cost rather than an estimate of it.

Trait Implementations

impl Clone for GpuPasses

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for GpuPasses

impl Debug for GpuPasses

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

Formats the value using the given formatter.

impl Default for GpuPasses

fn default() -> Self

Returns the “default value” for a type.

impl Eq for GpuPasses

impl PartialEq for GpuPasses

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for GpuPasses