double ViewDistance = 0.9;
private int DrawSystems(List<Data.System> Systems, Rectangle ScreenRectangle)
{
    var DefaultOption = new SystemDrawOptions();
    int DrawnSystems = 0;
    List<Data.System> SystemsWithText = new List<Data.System>();

    var bitmap = new Bitmap(img);
    var bitmapData = bitmap.LockBits(
        new Rectangle(System.Drawing.Point.Empty, img.Size),
        ImageLockMode.ReadWrite, PixelFormat.Format32bppArgb);
    var bitsPerPixel = (((int)bitmapData.PixelFormat >> 8) & 0xFF) / 8;
    int bWidth = bitmap.Width,
        bHeight = bitmap.Height;

    unsafe
    {
        var pixelDataPointer = (byte*)bitmapData.Scan0;

        foreach (var system in Systems)
        {
            var Options = DefaultOption;
            if (Style.ContainsKey(system))
                Options = Style[system];

            int DrawSize = 2;
            if (Options.Size > 0)
                DrawSize = Options.Size;



            var DrawRect = GetSystemScreenRect(system, ScreenRectangle, DrawSize);
            var CheckRect = new Rectangle(new System.Drawing.Point(ScreenRectangle.X - DrawSize, ScreenRectangle.Y - DrawSize), new System.Drawing.Size(ScreenRectangle.Width + DrawSize * 2, ScreenRectangle.Height + DrawSize * 2));
            if (DrawRect.IntersectsWith(CheckRect))
            {

                if (DrawRect.X > 0 && DrawRect.X < bWidth &&
                    DrawRect.Y > 0 && DrawRect.Y < bHeight)
                {

                    var target = bitmapData.Stride * DrawRect.Y + 0 + DrawRect.X * bitsPerPixel;
                    pixelDataPointer[target] = (byte)(255 + pixelDataPointer[target]); //Blue
                    pixelDataPointer[target + 1] = (byte)(255 + pixelDataPointer[target + 1]); //Green
                    pixelDataPointer[target + 2] = (byte)(255 + pixelDataPointer[target + 2]); //Red

                }

                if (Options.ShowName || Options.Text != null)
                    SystemsWithText.Add(system);

                DrawnSystems++;
            }
        }

    }
    bitmap.UnlockBits(bitmapData);
    img = bitmap;
    graphics = Graphics.FromImage(img);
    foreach (var system in SystemsWithText)
    {
        var Options = DefaultOption;
        if (Style.ContainsKey(system))
            Options = Style[system];

        int DrawSize = 1;
        if (Options.Size > 0)
            DrawSize = Options.Size;

        var DrawRect = GetSystemScreenRect(system, ScreenRectangle, DrawSize);
        var CheckRect = new Rectangle(new System.Drawing.Point(ScreenRectangle.X - DrawSize, ScreenRectangle.Y - DrawSize), new System.Drawing.Size(ScreenRectangle.Width + DrawSize * 2, ScreenRectangle.Height + DrawSize * 2));
        if (DrawRect.IntersectsWith(CheckRect))
        {

            var Pos = DrawRect.Location + DrawRect.Size;
            if (Options.ShowName)
            {
                graphics.DrawString(system.name, System.Drawing.SystemFonts.DefaultFont, StarBrush, Pos);
                Pos.Y += 15;
            }

            if (Options.Text != null)
            {
                graphics.DrawString(Options.Text, System.Drawing.SystemFonts.DefaultFont, StarBrush, Pos);
            }
        }
    }


    return DrawnSystems;
}