Choose how often OnBar fires (once per closed bar, on every price change, or on every tick) and tell a close from an intra-bar update.

Calculation cadence

The Calculate property sets how often OnBar runs. Set it in OnInitialize. It uses the same CalculationMode enum and the same default as an indicator's Calculate. The default, OnBarClose, fires once per completed bar and suits most strategies: it is cheaper, deterministic, and free of noise from a bar that is still forming.

C#using SabrTrader.Pipeline.Indicators;   // CalculationMode

protected override void OnInitialize()
{
    Calculate = CalculationMode.OnEachTick;
}

The closing OnBar for a bar fires exactly once in every mode. An intra-bar mode adds callbacks and never removes one, so logic written for OnBarClose still gets its per-close call.

Telling a close from an intra-bar update

Under OnPriceChange and OnEachTick the same OnBar hook fires inside the forming bar and at its close, and during an intra-bar call CurrentBar is the developing bar. Two flags tell the calls apart:

• IsBarClosed: true on a closing callback (always true under OnBarClose), false during an intra-bar update. Gate once-per-bar work on it.
• IsFirstTickOfBar: true on the first intra-bar tick of a newly opened bar, false on a closing callback. Run "new bar opened" logic once with it.

C#protected override void OnBar()
{
    if (IsFirstTickOfBar) { /* a new bar just opened */ }

    // intra-bar: react to the developing close
    if (!IsBarClosed) { TightenStopIfNeeded(CurrentBar.Close); return; }

    // closed bar: the once-per-bar entry logic
    EvaluateSignal();
}

TryGetOrderFlowBar(0, …) returns false during an intra-bar call: only closed bars carry a final order-flow snapshot.