Module events

Event creation, evaluation, and batch manipulation utilities.

Covers RPE events (moveX, moveY, rotate, alpha, speed), color events, text events, gif events, and extended properties.

Key concepts

• Beat tuple [measure, numerator, denominator] — see toBeats / fromBeats.
• Event evaluation — use getEventValue to sample an event at a beat, or evaluateAllEventLayers for a full line state.
• Speed height — use computeHeight to get the accumulated scroll position from speed events (replicates Line.handleSpeed).
• Batch ops — offsetEvents, scaleEventTimes, scaleEventValues, keyframesToEvents, copyEvents.

Examples

import { toBeats, fromBeats, getTimeSec, createEvent, keyframesToEvents } from './events';

// Convert a beat tuple to a fractional beat
toBeats([2, 1, 4]); // 2.25

// Convert back
fromBeats(2.25); // [2, 1, 4]

// Create an event that moves a line from X=-675 to X=675 over beats 0Ⅎ4
const ev = createEvent(0, 4, -675, 675, 'cubicOut');

// Build keyframe animation: X moves 0→100→0 over beats 0Ⅎ2→4
const evs = keyframesToEvents([[0, 0], [2, 100], [4, 0]], 'sineInOut');
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