NmeaParser/src/SampleApp.WinDesktop/AltitudeGraph.xaml.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace SampleApp.WinDesktop
{
    /// <summary>
    /// Interaction logic for AltitudeGraph.xaml
    /// </summary>
    public partial class AltitudeGraph : UserControl
    {
        Queue<double> datapoints = new Queue<double>();
        double min = double.MaxValue;
        double max = double.MinValue;
        public AltitudeGraph()
        {
            InitializeComponent();
            MaxDatapoints = 150;
        }

        public void AddDataPoint(double value)
        {
            if (double.IsNaN(value))
                return;
            datapoints.Enqueue(value);
            min = Math.Min(value, double.IsNaN(min) ? value : min);
            max = Math.Max(value, double.IsNaN(max) ? value : max);
            if (datapoints.Count > MaxDatapoints)
            {
                double val = datapoints.Dequeue();
                //If this is the limiting value, recalculate min/max
                if (val == min)
                    min = datapoints.Min();
                if (val == max)
                    max = datapoints.Max();
            }
            UpdatePath();
            mintb.Text = min.ToString("0");
            maxtb.Text = max.ToString("0");
        }

        private void UpdatePath()
        {
            if(!datapoints.Any())
            {
                path.Data = null;
                return;
            }
            var data = datapoints.ToArray();
            List<PathSegment> segments = new List<PathSegment>();
            for(int i=1;i<data.Length;i++)
            {
                segments.Add(new LineSegment(new Point(i, max - data[i]), true));
            }
            PathFigure pf = new PathFigure(new Point(0, max - data[0]), segments, false);
            path.Data = new PathGeometry(new PathFigure[] { pf });

        }
        public int MaxDatapoints { get; set; }



        public double Value
        {
            get { return (double)GetValue(ValueProperty); }
            set { SetValue(ValueProperty, value); }
        }

        // Using a DependencyProperty as the backing store for Value.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty ValueProperty =
            DependencyProperty.Register("Value", typeof(double), typeof(AltitudeGraph), new PropertyMetadata(0d, OnValuePropertyChanged));

        private static void OnValuePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            ((AltitudeGraph)d).AddDataPoint((double)e.NewValue);
        }

        
    }
}