declare type ColorFunc = (grad: number, fastMode: boolean, output: number[]) => void; declare type ColorState = 'inRange' | 'outOfRange'; declare class HeatmapLayer { canvas: HTMLCanvasElement; blurSize: number; pointSize: number; maxOpacity: number; minOpacity: number; private _brushCanvas; private _gradientPixels; constructor(); update(data: number[][], width: number, height: number, normalize: (value: number) => number, colorFunc: Record, isInRange?: (grad?: number) => boolean): HTMLCanvasElement; _getBrush(): HTMLCanvasElement; _getGradient(colorFunc: Record, state: ColorState): Uint8ClampedArray; } export default HeatmapLayer;