Poor performance when using VisualXcceleratorRenderSurface and IRenderContext.DrawPolygon

I’m experimenting with creating a CustomRenderableSeries.

I was expecting VisualXcceleratorRenderSurface to perform the fastest. But what I am finding is that it is noticeably slower than XamlRenderSurface. By slower, I mean interaction with zoom/pan becomes choppy and resizing the window is choppy. Which is surprising because I’m really not rendering much at all.

We plan on rendering a lot more than this, but it already appears to struggling. Can you shed some light?

public class MyDataSeries : XyDataSeries<double>
{
    public MyDataSeries()
    {

    }
}

public class MyRenderableSeries : CustomRenderableSeries
{
    public MyRenderableSeries()
    {

    }

    protected override void Draw(IRenderContext2D renderContext, IRenderPassData renderPassData)
    {
        base.Draw(renderContext, renderPassData);

        if (DataSeries is not MyDataSeries series)
            return;

        using (var brush = renderContext.CreateBrush(Brushes.Red))
        using (var pen = renderContext.CreatePen(Colors.Black, true, 1))
        {
            for (int i = 0; i < series.Count; ++i)
            {
                double pos = (double)series.XValues[i];

                var x = renderPassData.XCoordinateCalculator.GetCoordinate(pos);
                var y = renderPassData.YCoordinateCalculator.GetCoordinate(pos);
                var s = renderPassData.XCoordinateCalculator.GetCoordinate(0) - renderPassData.XCoordinateCalculator.GetCoordinate(1);

                var points = CreateCircle(new Point(x, y), s);
                renderContext.FillPolygon(brush, points);
            }
        }
    }

    private List<Point> CreateCircle(Point pos, double radius)
    {
        var points = new List<Point>();

        int count = 1000;
        for (int i = 0; i < count; ++i)
        {
            double angle = (360.0 / count * i) * (Math.PI / 180);
            double x = Math.Cos(angle) * radius;
            double y = Math.Sin(angle) * radius;

            points.Add(new Point(pos.X + x, pos.Y + y));
        }

        points.Add(points[0]);

        return points;
    }
}

public class MyRenderableSeriesViewModel : BaseRenderableSeriesViewModel
{
    public override Type ViewType => typeof(MyRenderableSeries);
}

public class MyViewModel : BaseViewModel
{
    public List<IRenderableSeriesViewModel> RenderableSeriesViewModels { get; }

    public MyViewModel()
    {
        RenderableSeriesViewModels = new List<IRenderableSeriesViewModel>
        {
            Generate(Enumerable.Range(0, 25).Select(x => (double)x).ToArray()),
        };
    }

    private IRenderableSeriesViewModel Generate(double[] data)
    {
        var dataSeries = new MyDataSeries();
        dataSeries.Append(data, data);

        return new MyRenderableSeriesViewModel
        {
            DataSeries = dataSeries,
            StyleKey = "mySeriesStyle"
        };
    }
}


<UserControl x:Class="SciChart.Examples.Examples.SeeFeaturedApplication.Histogram.ViolinView"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:s="http://schemas.abtsoftware.co.uk/scichart"
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
         xmlns:local="clr-namespace:SciChart.Examples.Examples.SeeFeaturedApplication.Histogram"
         mc:Ignorable="d">

<UserControl.Resources>
    <ResourceDictionary>
        <ResourceDictionary.MergedDictionaries>
            <ResourceDictionary Source="/SciChart.Charting;component/Themes/Default.xaml" />
        </ResourceDictionary.MergedDictionaries>

        <Style TargetType="{x:Type local:MyRenderableSeries}"
               BasedOn="{StaticResource MvvmDefaultRenderableSeriesStyle}"
               x:Key="mySeriesStyle">
        </Style>
    </ResourceDictionary>
</UserControl.Resources>

<s:SciChartSurface x:Name="SciChart"
                   RenderableSeries="{s:SeriesBinding RenderableSeriesViewModels}">
    <s:SciChartSurface.RenderSurface>
        <s:VisualXcceleratorRenderSurface />
    </s:SciChartSurface.RenderSurface>

    <s:SciChartSurface.XAxis>
        <s:NumericAxis />
    </s:SciChartSurface.XAxis>

    <s:SciChartSurface.YAxis>
        <s:NumericAxis />
    </s:SciChartSurface.YAxis>
    <s:SciChartSurface.ChartModifier>
        <s:ModifierGroup>
            <s:ZoomPanModifier />
            <s:RubberBandXyZoomModifier ExecuteOn="MouseRightButton" />
            <s:ZoomExtentsModifier ReceiveHandledEvents="False" />
            <s:MouseWheelZoomModifier />
        </s:ModifierGroup>
    </s:SciChartSurface.ChartModifier>
</s:SciChartSurface>

I have tested this on 3 machines, and all show the same behaviour.

**VisualXcceleratorEngine: Creating VisualXcceleratorRenderSurface Visual Xccelerator Engine v7.0.1.27055

GPU Capability Test ### Is BGRA feature required: TRUE

Examining Graphics Adapter: Intel(R) Iris(R) Xe Graphics VRAM:
128Mb DeviceId: 39497

Visual Xccelerator Engine Direct3D9 Compatibility
Determines whether the adapter is blacklisted due to its unstable work… FALSE
Trying to create Direct3D9 Device… SUCCESS

Visual Xccelerator Engine Direct3D11 Compatibility
Trying to create Direct3D9Ex Device (WPF Compatibility)… SUCCESS
Trying to create Direct3D11 Device… SUCCESS

Rank: 3000128 Points

Examining Graphics Adapter: NVIDIA T500 VRAM: 1928Mb DeviceId:
8123

Visual Xccelerator Engine Direct3D9 Compatibility
Determines whether the adapter is blacklisted due to its unstable work… FALSE
Trying to create Direct3D9 Device… FAILED

Visual Xccelerator Engine Direct3D11 Compatibility
Trying to create Direct3D9Ex Device (WPF Compatibility)… FAILED
Trying to create Direct3D11 Device… SUCCESS

Rank: 3001928 Points

Examining Graphics Adapter: Microsoft Basic Render Driver VRAM: 0Mb
DeviceId: 140

Visual Xccelerator Engine Direct3D9 Compatibility
Determines whether the adapter is blacklisted due to its unstable work… FALSE
Trying to create Direct3D9 Device… FAILED

Visual Xccelerator Engine Direct3D11 Compatibility
Trying to create Direct3D9Ex Device (WPF Compatibility)… FAILED
Trying to create Direct3D11 Device… SUCCESS

Rank: 2000000 Points

Selected Graphics Adapter, where DeviceId is: 8123 Is Direct3D9
Supported: FALSE Is Direct3D11 Supported: TRUE Is Blacklisted:
FALSE

Please find the log file here:
C:\dev\TestApps\SciChart_Violin\bin\Debug\net6.0-windows\GpuCapability.log

**VisualXcceleratorEngine: SUCCESS! VisualXcceleratorRenderSurface: attempt to initialize the engine with parameters: Use Direct3D9 –
False