User Control input / output with dynamic graphic elements or better use form?

I want to create something like a tool to control light color and intensity along time axis.

There are waypoints (in this simple example two: a pure green and a pure blue one) with specified color and intensity (the height of the polygon). Between the waypoints light is smoothly blended (therefore the gradient story...)

As there can be hundreds of waypoints, I need to have a long polygonal shape that would look more or less like the teeth of a saw. Each waypoint should be moveable in x and / or y direction with something like a rectangle (or maybe a button) that can be clicked with the mouse and then should make the waypoint moveable.

I want to know, if I can create such dynamic editable polygon "thing", namely my graphical light timeline representation via a user control, or if this works only within the main form...

So I need a dynamic control that resizes / reshapes itself dependent on user editing.

If this is possible with the custom control, how can I send / receive data like polygon point coordinates to / from it?

I have the following code that was put to a custom control to avoid flickering! Flickering is an important issue and may not appear in my app, so if you answer, please keep the flickering issues in mind!

---

The code of the custom control with a simpel 2-waypoint-example with green-to-blue color gradient,
works really FLICKER-FREE:

using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Windows.Forms;

namespace Test
{
  /// <summary>
  /// Summary description for GradientPanel.
  /// </summary>
  public class GradientPanel : System.Windows.Forms.UserControl
  {
    /// <summary>
    /// Required designer variable.
    /// </summary>
    private System.ComponentModel.Container components = null;

    public GradientPanel()
    {
      // This call is required by the Windows.Forms Form Designer.
      InitializeComponent();

      // Add any initialization after the InitializeComponent call
      this.SetStyle( ControlStyles.UserPaint, true );
      this.SetStyle( ControlStyles.AllPaintingInWmPaint, true );
      this.SetStyle( ControlStyles.DoubleBuffer, true );
      this.SetStyle( ControlStyles.SupportsTransparentBackColor, true );

      this.BackColor = Color.Transparent;

    }

    /// <summary>
    /// Clean up any resources being used.
    /// </summary>
    protected override void Dispose( bool disposing )
    {
      if( disposing )
      {
        if(components != null)
        {
          components.Dispose();
        }
      }
      base.Dispose( disposing );
    }

    #region Component Designer generated code
    /// <summary>
    /// Required method for Designer support - do not modify
    /// the contents of this method with the code editor.
    /// </summary>
    private void InitializeComponent()
    {
      //
      // GradientPanel
      //
      this.Name = "GradientPanel";
      this.Size = new System.Drawing.Size(240, 212);
      this.Resize += new System.EventHandler(this.GradientPanel_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.GradientPanel_Paint);

    }
    #endregion

    private void GradientPanel_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {
   
      Graphics g = e.Graphics;

      Point[] PolyPoints = new Point[4];
      PolyPoints[0] = new Point(0, 0);
      PolyPoints[1] = new Point(this.Width, 0);
      PolyPoints[2] = new Point(this.Width, this.Height);
      PolyPoints[3] = new Point(0, this.Height / 2);

      LinearGradientBrush myBrush =
        new LinearGradientBrush(new Point(0,0), new Point(this.Width, 0),
        Color.Green, Color.Blue);

      g.FillPolygon(myBrush, PolyPoints, FillMode.Alternate);

      myBrush.Dispose();

    }

    private void GradientPanel_Resize(object sender, System.EventArgs e)
    {
      this.Invalidate();
    }

  }
}



*********************

The code of the simple demo app:


using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace Flicker1
{
       public class Form1 : System.Windows.Forms.Form
       {
                private Test.GradientPanel gradientPanel1;
                private System.ComponentModel.Container components = null;

                public Form1()
      {
             InitializeComponent();
           }

      protected override void Dispose( bool disposing )
      {
                  if( disposing )
              {
            if (components != null)
                         {
                  components.Dispose();
                       }
               }
                 base.Dispose( disposing );
        }

          #region
           private void InitializeComponent()
           {
            System.Resources.ResourceManager resources = new System.Resources.ResourceManager(typeof(Form1));
            this.gradientPanel1 = new Test.GradientPanel();
            this.SuspendLayout();
            //
            // gradientPanel1
            //
            this.gradientPanel1.BackColor = System.Drawing.Color.Transparent;
            this.gradientPanel1.Location = new System.Drawing.Point(40, 32);
            this.gradientPanel1.Name = "gradientPanel1";
            this.gradientPanel1.Size = new System.Drawing.Size(696, 176);
            this.gradientPanel1.TabIndex = 0;
            this.gradientPanel1.MouseMove += new System.Windows.Forms.MouseEventHandler(this.gradientPanel1_MouseMove);
            //
            // Form1
            //
            this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
            this.BackgroundImage = ((System.Drawing.Image)(resources.GetObject("$this.BackgroundImage")));
            this.ClientSize = new System.Drawing.Size(800, 422);
            this.Controls.Add(this.gradientPanel1);
            this.Name = "Form1";
            this.Text = "Form1";
            this.ResumeLayout(false);

        }
      #endregion
 
      [STAThread]
      static void Main()
       {
      Application.Run(new Form1());
       }

        private void gradientPanel1_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e)
        {
            gradientPanel1.Width = Cursor.Position.X;
            gradientPanel1.Refresh();    
        }
    }
}


Thank you very much for helping me with this issue!