GlobalMetric(ctx *traceContext, ev *trace.Event)

	// Goroutine parts.
	GoroutineLabel(ctx *traceContext, ev *trace.Event)
	GoroutineRange(ctx *traceContext, ev *trace.Event)
	GoroutineTransition(ctx *traceContext, ev *trace.Event)

	// Proc parts.
	ProcRange(ctx *traceContext, ev *trace.Event)
	ProcTransition(ctx *traceContext, ev *trace.Event)

	// User annotations.

func (e *Emitter) HeapAlloc(ts time.Duration, v uint64) {
	e.heapStats.heapAlloc = v
	e.emitHeapCounters(ts)
}

func (e *Emitter) Focus(id uint64) {
	e.focusResource = id
}

func (e *Emitter) GoroutineTransition(ts time.Duration, from, to GState) {
	e.gstates[from]--
	e.gstates[to]++
	if e.prevGstates == e.gstates {
		return
	}
	if e.tsWithinRange(ts) {
		e.OptionalEvent(&format.Event{