TimeDirection graph

A work college was wanting some trivial code to draw a time based direction plot, and insisted that I do it.

So here is my drawing class:

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Windows.Forms;

namespace LineCurve
{
    public class TimeDirection
    {
        public void Draw(Graphics g, Panel pnl, List<KeyValuePair<int,float>> data, int maxtime)
        {
            using (Brush brush = new SolidBrush(Color.Blue))
            {
                float halfx = pnl.Width / 2.0f;
                float halfy = pnl.Height / 2.0f;
                float scale = Math.Min(halfx, halfy) / (float)maxtime;

                foreach (KeyValuePair<int, float> kvp in data)
                {
                    int time = kvp.Key;
                    double dir = kvp.Value / 180.0 * Math.PI;

                    // subtrack y as 0 is top, and +y is bottom.
                    float fx = (float)(halfx + (Math.Sin(dir) * scale * time));
                    float fy = (float)(halfy - (Math.Cos(dir) * scale * time));

                    g.FillRectangle(brush,fx, fy, 1.0f, 1.0f);
                }
            }
        }
    }
}

And given the input:

List<KeyValuePair<int,float>> data = new List<KeyValuePair<int,float>>();
for (int i = 0; i < 40; i++)
{
    data.Add(new KeyValuePair<int, float>(i, i * 9.0f));
}

Looks like this:

time/direction based graph

This code is released under the MIT license, except it may not be used for web-based weather applications.

1 thought on “TimeDirection graph”

Comments are closed.