C#

Simon Stevens wrote:

it'll automatically open with the disassembly of the current project.

protected override void OnPaint(PaintEventArgs pe)
{
    base.OnPaint(pe);
    Graphics g = pe.Graphics;

    //if background isnt already prerendered
    if (bmp_background == null)
    {
        RenderBackGround(); //renders bmp_background 
    }
    
    //only re draw region that changes
    Rectangle R = pe.ClipRectangle;
    g.DrawImage(bmp_background, R.X, R.Y, R, GraphicsUnit.Pixel);

    //draw point (the small circle)
    DrawPoint(g,DrawingArea);
    //the drawingarea is a rectangle inside the control
    //you should consider it as (the control bounds - the padding of the control)
    // + a correction of the aspect ratio of this inside rectangle (has to be 1 all the time)
    // is used for the background and as a reference for the circle drawing position
    // locaction of the circle is stored in another object (and set by some mouse events)
}  

Luc Pattyn wrote:

if you drag a character "O" over the text "ABC"
starting at A and ending on C, how will your approach ever repaint the B