PassTimings

interface PassTimings

import type { PassTimings } from '@driftengine/core';

In depth

Not a widening of gpuTimer.ts, and that is deliberate. That class is a WebGL2 query pool over TIME_ELAPSED_EXT, partitioning a frame into three fixed brackets — shadows, reflection, rest — and it is right for what it measures. A graph pass is not one of three brackets: there are as many as the frame composes, they are named at record time, and on WebGPU the sample comes from a timestamp query rather than an elapsed-time extension. Two different measurements with two different shapes; widening one into the other would leave a class that does neither well.

What it does inherit from that class is its best rule: unmeasured is not zero. A device without timestamp queries, or a pass that ran no work, must not read as "took no time" — a profiler that cannot distinguish those two is a profiler that sends somebody optimising a pass that never ran. passMs returns null for unmeasured and a number for measured, including zero.

Labels persist and timings reset. A pass that did nothing this frame keeps its name and reports unmeasured, so the profiler's rows stop jumping about as quality settings toggle passes on and off — which is exactly when somebody is reading it.

Properties