README

Visual-Heatmap Js

Open source javascript module for rendering high performance, large scale heatmap.

Visual Heatmap is based on advanced graphical rendering context - WebGL/Shaders. It can render 500,000+ data points with a good framerate.

Click me Click me Click me

Installing

If npm

npm i visual-heatmap --save

Download source code from below links

Visual-Heatmap is written in ES6 Modules. To import use below syntax

Importing everthing into namespace

import Heatmap from 'visual-heatmap'

VisualHeatmapJs - API

visualHeatmap()

visualHeatmap provides a API to create context WebGL. API accepts containerId and config as an input. A layer will be created under the provided Div #containerId.

let instance = Heatmap('#containerId', {
        size: 30.0,
        max: 100,
        blur: 1.0,
        gradient: [{
            color: [0, 0, 255, 1.0],
            offset: 0
        }, {
            color: [0, 0, 255, 1.0],
            offset: 0.2
        }, {
            color: [0, 255, 0, 1.0],
            offset: 0.45
        }, {
            color: [255, 255, 0, 1.0],
            offset: 0.85
        }, {
            color: [255, 0, 0, 1.0],
            offset: 1.0
        }]
    });

ContainerId CSS Query selector which identifies container.

Config Object with config properties.

{
size : Radius of the data point, in pixels.
max : Max data Value for relative gradient computation.
blur : Blur factor.
opacity : Opacity factor.
rotationAngle : Rotation angle.
translate : translate vector [x, y].
zoom : Zoom Factor.
gradient : Color Gradient, array of objects with color value and offset.
}

instance.renderData([])

Accepts an array of data points with 'x', 'y' and 'value'. Demo

instance.addData([], transformationIntactflag);

Accepts an array of data points with 'x', 'y' and 'value' and a flag to specify to apply existing canvas transformations on the newly added data points. Try Example

instance.setMax()

To set max data value, for relative gradient calculations.

instance.setTranslate()

Api to perform translate transformation on the canvas. Accepts array[x, y] as an input. Try Example

instance.setZoom()

Api to perform zoom transformation on the canvas. Accepts float value as an input. Try Example

instance.setRotationAngle()

Api to perform rotation transformation on the canvas. Accepts angle in radians. Try Example

instance.setSize()

Api to set point radius. Accepts float value as an input. Try Example

instance.setBlur()

Api to set Blur factor. Accepts float value as an input. Try Example

instance.setOpacity()

Api to set Opacity factor. Accepts float value as an input. Try Example

instance.clear()

Api to clear canvas.

Usage no npm install needed!