Show tempo and tap tempo
Draft documentation: This document was created with the help of AI and has not yet been fully reviewed by a human.
Nightfall keeps one tempo for the whole show. The Tempo panel shows it as a BPM readout with a row of beat dots, where the larger dot is beat 1 of the bar, and holds the Tap pad and the controls below. Open it from the Command Palette, or keep it in your performance layout. To tap from a busking board, add a Tempo element to the board: it shows the BPM and beat dots, and pressing it taps. Everything that follows the tempo, such as the Show Tempo flow node and effects and sequences whose Timing is set to Beats in the FX Editor or Sequence Editor, reads this same clock.
Tapping a tempo
Press Tap in the Tempo panel on the beat. The button responds the moment you press it, so tap on the attack of the beat rather than on release.
- The first tap marks beat 1. If you haven't tapped for more than 3.5 seconds, your next tap is treated as a downbeat. It moves the bar so that tap becomes beat 1 and leaves the tempo unchanged.
- Each tap after that refines the tempo. From the second tap on, Nightfall fits a steady beat through your recent taps. The BPM comes from their spacing, and the beat is pulled into line with where you tapped.
- Only your last 8 taps count. Tapping longer does not keep averaging. Once you have tapped about 8 times, the tempo follows the most recent 8 taps (roughly two bars). That lets you keep tapping to follow a song that speeds up or slows down, and older taps stop influencing the result.
- A stray tap starts a fresh count. A tap that lands more than 40% early or late compared with the current beat spacing is not averaged in. A double tap or a skipped beat are typical examples. Nightfall keeps the current tempo and starts counting again from that tap, so the next few taps set the tempo.
- Taps are timed where you make them. The Tap button records the moment you pressed it on your own device, so network delay and the engine's frame rate do not change the tempo you tap. Taps from two devices are not mixed: a tap from a different device starts a fresh count.
- Stopping is safe. When you stop tapping, the tempo keeps running at the last value.
For the steadiest result, tap 8 or more beats evenly. To mark where the bar starts, pause for a few seconds and then tap on the "1".
Changes never jump
Tempo changes glide rather than jump, so chases and effects running on the beat keep playing smoothly instead of skipping or restarting.
- New tempos glide in over about one beat. Going from 120 to 128 BPM takes about half a second.
- Beat alignment changes from taps, Resync or Nudge are spread over about one bar. The beat runs slightly fast or slow until it lines up, never more than 25% off speed. Larger corrections take longer: in 4/4, shifting the beat by two whole beats takes about two bars.
Jump to next downbeat is the one exception. It moves straight to the start of the next bar.
Tempo controls
The Tempo panel has these controls next to the Tap pad.
| Control | What it does |
|---|---|
| Tempo (BPM) | Type a tempo between 20 and 300 BPM, or use the − and + buttons. Typed values apply when you press Enter, leave the field, or pause typing. |
| Beats per bar | Sets the bar length from 1 to 16 beats. The bar you are in keeps its downbeat and the bar count carries on, so changing the length mid-song does not shift where bars start. |
| Half time / Double time | Halves or doubles the tempo. |
| Resync to downbeat | Makes this moment beat 1 of a bar without changing the tempo. Use it when the tempo is right but the "1" has drifted. |
| Jump to next downbeat | Skips straight to the start of the next bar. |
Launch quantize
Launch quantize in the Tempo panel makes live clip launches land on the beat. It is a show setting with three choices:
- Off: clips start and stop as soon as you press them.
- Beat: starts, Go presses and stops wait for the next beat.
- Bar: they wait for the next downbeat.
A press that lands just after the beat or downbeat (within a twentieth of a beat) fires straight away rather than waiting a whole beat or bar. While a clip waits, its slot button and any board button for it pulse. Pressing the same button again before the beat cancels the launch, and stopping a clip that is still waiting to start cancels its start.
Launch armed clips now (the lightning button in the Tempo panel toolbar, also available as a mappable action) fires everything that is waiting straight away.
Held Flash and Swop buttons always act at once, and timeline and flow playback never wait.
Commands
The command line controls the same tempo.
tempo 128
tempo tap
tempo half
tempo double
tempo resync
tempo snap
tempo nudge -0.25
tempo bar 3
tempo snap jumps to the next downbeat. tempo nudge shifts the beat by a number of beats: a positive value moves the beat earlier, a negative value moves it later. tempo bar sets the beats per bar.
Because tempo, tap, half, double, resync, snap, nudge and bar are command words, they can't be used as custom attribute names.
MIDI and OSC
In the MIDI Input and OSC Input mapping tables, these actions control the tempo:
| Action | Effect |
|---|---|
TapTempo | One tap, with the same rules as the Tap button. |
ResyncTempo | Resync to downbeat. |
SetTempo(128) | Sets the tempo in BPM. |
MultiplyTempo(0.5) | Multiplies the tempo, for example 0.5 for half time and 2 for double time. |
NudgeTempo(-0.25) | Shifts the beat by the given number of beats. |
Tempo actions run when a button is pressed and ignore the release. Taps from a MIDI or OSC controller are timed the moment the message arrives.
Flows
The Show Tempo node outputs the current BPM, the Beat within the bar and the Bar count (both starting at 1), and the Phase through the current beat from 0 to 1. Its On Beat and On Bar triggers fire once for every beat and every downbeat.
Saved with the show
The tempo, beats per bar and launch quantize mode are saved in the showfile. Opening a show restores them straight away, without gliding from the previous tempo. A new show starts at 120 BPM in 4/4.