echarts
Version:
Apache ECharts is a powerful, interactive charting and data visualization library for browser
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TypeScript
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();
/**
* Renders Heatmap and returns the rendered canvas
* @param data array of data, each has x, y, value
* @param width canvas width
* @param height canvas height
*/
update(data: number[][], width: number, height: number, normalize: (value: number) => number, colorFunc: Record<ColorState, ColorFunc>, isInRange?: (grad?: number) => boolean): HTMLCanvasElement;
/**
* get canvas of a black circle brush used for canvas to draw later
*/
_getBrush(): HTMLCanvasElement;
/**
* get gradient color map
* @private
*/
_getGradient(colorFunc: Record<ColorState, ColorFunc>, state: ColorState): Uint8ClampedArray;
}
export default HeatmapLayer;