export declare class SpatialGrid {
    private _cells;
    private _xMin;
    private _yMin;
    private _cellSize;
    private _cols;
    constructor(xMin: number, xMax: number, yMin: number, yMax: number, cellSize: number);
    private _cellKey;
    insert(index: number, x: number, y: number): void;
    /**
     * Find the nearest point to (dataX, dataY) within the given radius,
     * measured in pixel distance using the provided scale factors.
     */
    query(dataX: number, dataY: number, radiusPx: number, pxPerDataX: number, pxPerDataY: number, xData: Float32Array, yData: Float32Array): number;
}