How to change the startX on a UniformHeatmapDataSeries?

Hi Paul

The UniformHeatmapDataSeries doesn’t have a way to modify or change the xStart, xStep, yStart, yStep properties after construction. However, the heatmap simply wraps a 2d array so the overhead to create a new UniformHeatmapDataSeries and assign it to the RenderableSeries is quite low.

This is how you might update the heatmap series position dynamically:

    const zValues: number[][] = ...

    const heatmapData = new UniformHeatmapDataSeries(webAssemblyContext, { 
        xStart: 0,
        xStep: 1,
        yStart: 0,
        yStep: 1,
        zValues
    });

    const heatmapRenderSeries = new UniformHeatmapRenderableSeries(webAssemblyContext, { dataSeries: heatmapData });

    // Later, you want to update data but not recreate the chart
    heatmapRenderSeries.dataSeries = new UniformHeatmapDataSeries(webAssemblyContext, {
        xStart: 100,
        xStep: 1,
        yStart: 100,
        yStep: 1,
        zValues
    }); 

Any time you assign a new UniformHeatmapDataSeries to the RenderableSeries.DataSeries property the chart will redraw.

Note: you can have multiple heatmap series on a single SciChartSurface (tiling is possible). I would suggest as well as paging to tile and create new heatmap RenderableSeries/DataSeries pairs and add them on to the chart, removing when the chart zooms them out of scope. The memory is held in the zValues[][] array passed into UniformHeatmapDataSeries constructor so if you want to be memory efficient, re-use that array.

Lastly, don’t forget if you do remove and discard any RenderableSeries/DataSeries from a SciChartSurface to call .delete() on them to ensure any native memory is freed.

Let me know if this helps

Best regards,
Andrew