LightningChart JS Releases

WebAssembly.Memory Utilization

• LightningChart JS can now allocate far more memory than a standard browser page allows, by making use of WebAssembly.Memory. This is a built-in, well supported browser capability, and in LightningChart JS it is enabled by passing a single flag.
• The practical effect is that the amount of data you can load is no longer governed by a hard browser limit. It is governed by the physical RAM in the machine running the application. Actual behaviour and performance vary between browsers, but across testing the pattern held: the more RAM the hardware has, the more data LightningChart JS can hold.

Automatic Data Sorting Within Batch

• From v9.1.0 onward, LightningChart JS automatically sorts incoming data when the data schema is declared as progressive.

Per-Data-Point Colouring for 3D Line Series

• LineSeries3D and PointLineSeries3D now support IndividualPointFill, so every data point in a 3D line series can be coloured separately and programmatically.
• This brings 3D line series into line with what was already possible in 2D, and it matters most when the colour is carrying a third or fourth variable: signal amplitude along a flight path, temperature along a pipe run, or classification state along a trajectory.

Heatmap solveNearest From an Axis Coordinate

• Heatmap series gain a new solveNearest syntax that resolves the nearest original data point to an arbitrary axis location given as X and Y.
• Previously this kind of lookup started from a screen position. Starting from an axis coordinate instead makes it straightforward to drive a heatmap readout from something other than the mouse: a shared cursor across several charts, a value typed into a field, or a position streamed in from another part of the application.

3D Series Interaction Events Report Original Data Samples

• User interaction events on 3D series, including pointermove, pointerenter, click and dblclick, now report full original data sample information, in the same way XY series have done for some time.
• The immediate benefit is synchronised interaction between 2D and 3D views of the same data. Hovering a point in a 3D scatter can now highlight the exact same sample in an XY time series beside it, without the application having to reverse-engineer which sample was hit.

Improved Gauge Chart Value-Settling Animations

• Gauge chart animations have been reworked so that the needle settles on a new value more smoothly. The difference is most visible on gauges driven by live data, where frequent small updates previously produced a busier movement than the underlying signal warranted.

Highlights:

• The DataSet Update:
  • The DataSet system has now been extended to cover 3D series and AreaRangeSeries, brought multi-threaded real-time FIFO data streaming, and gained new data property capabilities that make complex multi-series applications far simpler to architect.
• Updated MCP Server and Documentation:
  • The official LightningChart JS MCP Server makes it easier than ever to develop high-performance data visualization with AI agents. Install the MCP server and your agent switches from general-purpose open-source charting libraries to the most performance-optimized charts available for the web. The MCP server now supports both STDIO and HTTPS transport, making it compatible with the widest range of agent environments: Claude Code, Cursor, Windsurf, Cline, Roo Code, OpenAI Codex and VS Code tools.
• Negative Log Axes and Symlog Charts:
  • LightningChart JS logarithmic axes now support negative values. This is a frequently requested capability in scientific and financial visualization, where data spans both positive and negative domains but the magnitude of change is more meaningful than the absolute value.
  • Symlog charts: Combining negative log axis support with stacked axes and the DataSet API, it is now possible to build a symlog chart a single chart that applies negative logarithmic scaling below zero, a linear scale near zero, and positive logarithmic scaling above zero. This chart type is particularly valuable in financial analytics, chemistry, and any domain where data spans many orders of magnitude on both sides of zero.
• Multi-Threaded Real-Time Streaming:
  • It is now possible to separate data-receiving work from the browser's main thread using the Web Workers API, freeing the main thread entirely for rendering and user interaction.
  • In internal testing, this approach achieved 20 charts each with 10 trends at 50,000 Hz, sustained at 60 FPS. That is 10 million data points per second displayed in a single web application, a number that has never been achievable in a browser environment before.
  • The new multi-threaded streaming system supports both FIFO (first-in, first-out) scrolling and garbage-collected history management, so long-running sessions do not accumulate unbounded memory even at high data ingestion rates.
• Reworked AreaRangeSeries:
  • AreaRangeSeries has been fully migrated to the DataSet-based design used by XY line, point, and other series types.
  • Massively improved performance: AreaRangeSeries performance is now on par with XY line and point series. Previous versions used a separate rendering path that limited the amount of data AreaRangeSeries could handle smoothly. With the DataSet migration, AreaRangeSeries can visualize the same data volumes as any other series type, at the same frame rates.
  • DataSet connectivity and memory sharing: AreaRangeSeries can now connect directly to LC DataSet objects. A single DataSet can feed a line series, a point series, and an AreaRangeSeries simultaneously with zero memory duplication.
  • This is a backwards incompatible change.
• DataSet Follow Mode:
  • DataSets can now be built by adding additional data properties on top of an existing DataSet object. This is useful in architectures where you have a top-level data routing layer that receives and stores incoming streams, but which does not know how the data will be visualized.
  • With DataSet Follow mode, the visualization layer can hook up to an upstream DataSet and select any columns from it to display in any series type, without duplicating any memory.
• DataSet Derived Data Properties:
  • The Derived Properties API allows you to pass custom math functions to a DataSet object to automatically calculate additional data columns as source data is fed in. A practical example: adding a Simple Moving Average (SMA) column to an incoming price feed without manual calculation in your data pipeline.
• 3D Series DataSet Connection and Automatic Data Cleaning:
  • 3D line series and 3D point series now connect to LC DataSet objects, enabling the same management APIs as XY series: setMaxSampleCount, readBack, and all other DataSet operations. A single DataSet can now feed both a standard XY chart and a 3D chart simultaneously with no memory duplication.
  • This change is accompanied by heavy performance optimizations to 3D series rendering, particularly for PointSeries3D. LiDAR point clouds and other high-density 3D datasets will see significant performance improvements simply by upgrading to v9.0.0.
• Freeform 3D Camera Movement:
  • Chart3D user interaction now supports a Blender-style, freeform 3D camera movement scheme. Standard 3D chart interaction uses orbit controls where the camera rotates around a fixed point. Freeform camera movement lets the user navigate through the 3D scene freely, moving position and changing the view direction independently. Ideal for exploring 3D LiDAR scenes, volumetric medical data, or any 3D dataset where the user needs to navigate inside the data rather than orbit around it.
• BigInt64Array Storage Support:
  • LC DataSet objects now directly support storing BigInt data types via BigInt64Array typed arrays. This covers three common use cases:
    • Nanosecond timestamps: Standard JavaScript floats lose precision for nanosecond Unix timestamps. BigInt64 stores them exactly.
    • Parquet files: Apache Parquet's INT64 type maps directly to BigInt64Array for lossless data loading.
    • Generic large integer storage: Any use case where integer data does not fit in float64.
  • The LC series do not support direct visualization of BigInt data type, so there is still a conversion step that must be done before. For details refer to the nanosecond timestamps guide. This change makes it easy to store the original BigInt alongside the converted values for usage in cursors, readback, custom interactions, etc.

More Information:

• Added setDataSet and other DataSetXY APIs to PointSeries3D, PointCloudSeries3D, LineSeries3D and PointLineSeries3D.
• Added DataSet.readBackSingle, PointLineAreaSeries.readBackSingle.
• Added DataSetOptions.followDataSet.
• Added combineAttachables for combining several series into 1 shared legend entry.
• Added DataSet capability to store bigint data types.
  • This was previously possible via nonNumeric option, but this was not optimal as internally they would be stored in Array rather than BigInt64Array.
  • bigint properties can't be connected to series (they still have to be converted to Float64 or other format for visualization), but this addition makes it easy to store the original bigint sample values for easy lookup if required.
• Added derived dataset property feature.
  • Allows specifying a custom calculation callback in DataSet schema for automatically calculating derived properties.
  • Additionally, built-in options are accessible via builtInDataDerivations.
• Default axis type changed from linear to linear-highPrecision.
  • More details and migration instructions can be found in migration guide.
• Improved and made changes to Chart3D camera interactions.
  • Allow rotating past north/south poles.
  • Allow zooming closer in.
  • Added new interaction options (not enabled by default) that are suitable for free navigation 3D visualizations. The default interactions revolve around 0,0,0 as the origin of interest.
• Made some improvements to text shadow rendering.
• Automatically hide ParallelCoordinateChart axis titles that would overlap.
  • If the mouse is placed over an axis title, it forces that title to be shown only.

• Fixed cursor point marker not displaying series colors in some cases.
• Fixed PointLineAreaSeries render issue where sometimes if entire dataset is just 1 point, it is not rendered.
• Fixed captureFrame and saveToFile outputting 2 copies of charts drawn on top with one being flipped vertically. Issue was only visible with transparent chart backgrounds.
• Fixed some drag user interactions activating immediately (on pointerdown) rather than on first movement (pointermove).
• Fixed [violation] permissions policy violation unload is not allowed in this document.
• Fixed charts hard-overriding their container DIVs position property at creation time.
• Fixed setting text: '' to text figure showing "Text".

• Added isUITick and isUIPointableTextBox type guards.
• Changed recommended approach for realizing nano/microsecond timestamp use cases.
  • You should use new dedicated method setDateOriginNanos.

• Fixed high resolution displays sometimes showing white border around charts.
• Fixed default heatmap cursor formatter always referring to charts default axis (title, units, etc.).
• Fixed DateTime label formatting sometimes being wrong in microsecond zoom level.

• Fixed ChartXY preventing use of normal Ctrl+C, Ctrl+V and other standard key bindings on the page.
• Fixed DateTime Axis formatting hours/minutes/seconds wrong in cursor. Bug was introduced in v8.3.0.
• Fixed some performance degradations on GPU usage on chart rendering especially with high resolution screens. Introduced in v8.3.0.
• Fixed XY series being able to show even while one of their axes is hidden with setVisible.
• Fixed htmlTextRenderer not showing text shadows (actually more like text borders).
• Fixed visible range only axis fitting not working properly in case where same axis has several series and one of them is completely outside view.

• Added SunBurstChart.
• Added axis.setZebraStripes to help visually distinguish different regions of the chart based on axis values.
• Added useAxisLayouts option to ZoomBandChart for mirroring axis layout from attached charts.
• Added RectangleSeries.setCursorBehavior.
• Added MapChart.setSeparateRegionVisible method to change visibility of separate regions on the MapChart.
• Added new alterSamplesByMatch syntax for altering all samples with specific property=value match.
• Added BarChart.setBaseline.
• Added PublicEngine.setOpacity, getOpacity.
• Added multi-threading performance optimizations as a built-in functionality.
• Bumped minimum TypeScript requirement from v4.1 to v4.3.
• Optimized chart resize operations to be more efficient.
• Reworked default theme styles and text shadow rendering for improved color contrast out of box.
• Improved ChartXY auto layout with limited space.
• Improved default colors for Light theme axis gridstrokes.
• Removed appendSamples offsetLookupValues and other equivalent parameters as well as readBack ids. These were replaced with offset back in v8.0 but some non-functioning references were mistakenly left in the typings.

• Fixed microseconds not included in DateTime cursor formatting until zooming to nanoseconds level.
• Fixed issues where cursor can stay visible after mouse moves away from chart (Pie chart, Funnel chart, Pyramid chart, Parallel coordinate chart).
• Fixed low resolution point borders with Circle point shape and point sizes larger than 100 pixels.
• Fixed date time cursor formatting errors on millisecond zoom level showing wrong hour depending on time zone.
• Fixed scaleTheme not affecting legend paddings and spacing between entries correctly.
• Fixed clicking on browser auto suggestion input field options sometimes firing restoreDefault interaction in charts.
• Fixed SurfaceScrollingGridSeries3D sometimes throwing unhandled errors with addValues and invalidateValues.

• Upgraded dependency of immutable from 4.0.0 to 4.3.8 in response to a vulnerability.

• Added LinearGaugeChart.
• Added high precision axis support to Chart3D.
• Added AxisTickStrategy.setCustomTickPlacement:
  • Allows specifying custom logic to override placement of axis ticks.
• Added PointLineAreaSeries.setRenderTransform:
  • New beta feature targeted to use cases where application often requires applying an affine transformation (scale+offset) to XY visualizations.
  • Render transform can be changed very rapidly and doesn't require any heavy recalculations.
• Added nonNumeric option to DataSetXY schema:
  • Allows storing arbitrary string values within library's internal data storage.
• Added API for adjusting sensitivity of points appearing with zooming of PointLineAreaSeries.
• Added chart.setPauseRendering.
• Added DataSetXYOptions.useSharedArrayBuffers.
• Added new map types for Nordic countries, Middle East, and Southeast Asia.

• Fixed BarChart value axis title positioned incorrectly when logarithmic.
• Fixed creating ZoomBandChart with candlesticks shown as line shows dataset warning.
• Fixed <code>PointLineAreaSeries</code> render error with progressive data when zoomed out extremely far, no data is shown at all.
• Fixed <code>PointLineAreaSeries</code> render error when axis has large margins, sometimes data is not rendered around the margin edge area even if there is data there.
• Fixed Polar printing out warnings to console.
• Fixed <code>ChartXY</code> pan interaction not working on mobile.
  • Bug introduced in v7.1.0.
• Fixed data mapping having value <code>undefined</code> resulting in "data supply error" Error.