Method resetLayoutIterator

src/coord/matrix/MatrixDim.ts:371–392

* Iterate leaves (they are layout units) if dimIdx === this.dimIdx. * Iterate levels if dimIdx !== this.dimIdx.

(
        it: ListIterator<MatrixCellLayoutInfo> | NullUndefined,
        dimIdx: number,
        startLocator?: MatrixXYLocator | NullUndefined,
        count?: number | NullUndefined,
    )

     * Iterate levels if dimIdx !== this.dimIdx.
     */
    resetLayoutIterator(
        it: ListIterator<MatrixCellLayoutInfo> | NullUndefined,
        dimIdx: number,
        startLocator?: MatrixXYLocator | NullUndefined,
        count?: number | NullUndefined,
    ): ListIterator<MatrixCellLayoutInfo> {
        it = it || new ListIterator<MatrixCellLayoutInfo>();
        if (dimIdx === this.dimIdx) {
            const len = this._leavesCount;
            const startIdx = startLocator != null ? Math.max(0, startLocator) : 0;
            count = count != null ? Math.min(count, len) : len;
            it.reset(this._cells, startIdx, startIdx + count);
        }
        else {
            const len = this._levels.length;
            // Corner locator is from `-this._levels.length` to `-1`.
            const startIdx = startLocator != null ? Math.max(0, startLocator + len) : 0;
            count = count != null ? Math.min(count, len) : len;
            it.reset(this._levels, startIdx, startIdx + count);
        }
        return it;
    }

    resetCellIterator(
        it?: ListIterator<MatrixDimensionCell>