WPF Mousemove is a noticeable lag

Question

I am making a UserControl called VolumeScrollBar to control the volume a video player I am working on. Now the problem I am having is when I slide my SwitchPath it moves noticeable slower than my mouse. How can I fix this ?

note: everything is working but the speed.

Also, I am not using the built in sliding bar because I do not like how it looks. So I designed my own Volume scroll bar in Adobe Illustrator.

here is my code behind:


  public partial class VolumeScrollBar : UserControl, INotifyPropertyChanged
    {
        
        private bool _handToolMove;
        private double _volume;
        private double _volumeOut;
        const double ValumeMaxHigh = 0.81;
        const double LocationMaxHigh = 0.69334;


        


        public double Volume
        {
            get => (double)GetValue(VolumeProperty);

            set
            {
                if (_volume == value) return;
                _volume = value;
                SetValue(VolumeProperty, value);
            }
        }


        public event PropertyChangedEventHandler PropertyChanged;
        private void OnPropertyChanged([CallerMemberName] string propName = "") =>
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propName));



        // Using a DependencyProperty as the backing store for LEDState.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty VolumeProperty =
            DependencyProperty.Register("Volume", typeof(double), typeof(VolumeScrollBar), new FrameworkPropertyMetadata(0.0, FrameworkPropertyMetadataOptions.AffectsRender, (o, e) => ((VolumeScrollBar)o).OnVolumeChanged()));
        
        private void OnVolumeChanged()
        {
           ChangeTheVolume(Volume);
        }


        private void ChangeTheVolume(double newVolume)
        {
            if (newVolume < 0 || newVolume > 100) return;

            newVolume = Math.Round(newVolume);
            double tempVolume = (ValumeMaxHigh * newVolume);
            ColorBarPath.Width = tempVolume;

            double pointX = (LocationMaxHigh * newVolume) + 46.11;
            Canvas.SetLeft(SwitchPath, pointX); // set the left position of rectangle to mouse X
            Displaytxb.Text = Convert.ToString(newVolume);

        }




        public VolumeScrollBar()
        {
            RenderOptions.ProcessRenderMode = RenderMode.SoftwareOnly;
            InitializeComponent();
          
        }

        private void SwitchPath_MouseDown(object sender, MouseButtonEventArgs e)
        {
            Cursor = Cursors.Hand;
            _handToolMove = true;
            SwitchPath.CaptureMouse();

        }

        private void SwitchPath_MouseMove(object sender, MouseEventArgs e)
        {
            if (_handToolMove)
            {
                Point v = e.GetPosition(VolumeScrollBarCanvas);
                Volume = 0.6933 * v.X + 1.24946035807;
            }

        }

        private void SwitchPath_MouseUp(object sender, MouseButtonEventArgs e)
        {
            if (_handToolMove)
            {
                Point v = e.GetPosition(VolumeScrollBarCanvas);
                Volume = 0.6933 * v.X + 1.25;
                SwitchPath.ReleaseMouseCapture();
                _handToolMove = false;
                Cursor = Cursors.Hand;
            }
           
           
        }
    }

here is my XAML code:

Accepted Answer

Hi,@Brandon Boone .Welcome Microsoft Q&A.

Generally, you can modify the control Slider through Style, Template and Dependency Property (Attached Property) to get the VolumeScrollBar you want in WPF.

The problem here is not the speed of rendering, but just in your geometric calculation. With the mouse movement, the volume did not zoom 1: 1. (In other words, as is y = mx+b, M needs to be 1).

Therefore, this line in SwitchPath_MouseMove -

  Volume = 0.6933 * v.X + 1.24946035807;

Would be better written as

  Volume = (v.X - 46.11) / ValumeMaxHigh;

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WPF Mousemove is a noticeable lag

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