Function packDataPointsWithXOffset

src/data/createDataStore.ts:98–116

(points: ReadonlyArray<DataPoint>, xOffset: number)

  const isTupleDataPoint = (p: DataPoint): p is DataPointTuple => Array.isArray(p);

  const packDataPointsWithXOffset = (points: ReadonlyArray<DataPoint>, xOffset: number): Float32Array => {
    if (!points || points.length === 0) return new Float32Array(0);

    const buffer = new ArrayBuffer(points.length * 2 * 4);
    const f32 = new Float32Array(buffer);

    // Hot path: keep logic minimal (validation happens elsewhere in option resolution).
    for (let i = 0; i < points.length; i++) {
      const p = points[i]!;
      const x = isTupleDataPoint(p) ? p[0] : p.x;
      const y = isTupleDataPoint(p) ? p[1] : p.y;

      // Subtracting before the Float32 cast preserves sub-ULP deltas for large x magnitudes.
      f32[i * 2 + 0] = x - xOffset;
      f32[i * 2 + 1] = y;
    }

    return f32;
  };

  const assertNotDisposed = (): void => {
    if (disposed) {