JavaScript Spline Line Chart

This demo application belongs to the set of examples for LightningChart JS, data visualization library for JavaScript.

LightningChart JS is entirely GPU accelerated and performance optimized charting library for presenting massive amounts of data. It offers an easy way of creating sophisticated and interactive charts and adding them to your website or web application.

The demo can be used as an example or a seed project. Local execution requires the following steps:

• Make sure that relevant version of Node.js is installed

• Open the project folder in a terminal:

    npm install              # fetches dependencies
    npm start                # builds an application and starts the development server
  

• The application is available at http://localhost:8080 in your browser, webpack-dev-server provides hot reload functionality.

Description

This example shows how to draw and style spline-series.

First create the series using chart method.

// Add a spline series using default X and Y axes.
const splineSeries = chart.addSplineSeries()

Option 1: Styling using a style object.

The first option for styling of series is to create a new object that contains the necessary information about visual settings. In the case of line-series, the object must be type of SolidLine to be visible.

// Create a new instance of visible solid line-style.
const strokeStyle = new SolidLine()
    // Set desired fill style of the stroke.
    .setFillStyle(
        // SolidLine can have only SolidFill fill-style.
        new SolidFill().setColor(ColorRGBA(96, 204, 232)),
    )
    // Set thickness of the stroke.
    .setThickness(5.0)

// Apply styling settings to the series.
splineSeries.setStrokeStyle(strokeStyle)

Option 2: Styling using a mutator function.

Usually, it can be even more easy to simply modify the existing Style of a component, rather than constructing a new one. This is done using so-called mutator-functions. Here's an example:

// Modify the previous Stroke style of a SplineSeries, by overriding its previous thickness.
splineSeries.setStrokeStyle((strokeStyle) => strokeStyle.setThickness(1.0))

Our coding practices include fluent, self-returning API, which allows us to easily call multiple setters in one statement.

splineSeries
    .setStrokeStyle(strokeStyle)
    // 'transparentFill' is a static constant
    // that needs to be imported from the library in order to be used.
    // It is used to draw things with transparent fill that aren't disposable
    // - like the points of a PointLineSeries.
    .setPointFillStyle(transparentFill)

API Links

• Solid LineStyle
• Solid FillStyle
• Transparent FillStyle
• RGBA color factory
• XY cartesian chart
• Spline series
• Scroll strategies
• Progressive random data generator

Support

If you notice an error in the example code, please open an issue on GitHub repository of the entire example.

Official API documentation can be found on LightningChart website.

If the docs and other materials do not solve your problem as well as implementation help is needed, ask on StackOverflow (tagged lightningchart).

If you think you found a bug in the LightningChart JavaScript library, please contact sales@lightningchart.com.

Direct developer email support can be purchased through a Support Plan or by contacting sales@lightningchart.com.

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