Question

I am trying to use an existing Bitmap image on a C# windows form which is a rendered MandleBrot Fractal. I want to implement colour cycling. It must be done with with the use of a pallete image. Here is my code I am stuck for days now and can’t get it to work. The code must be inside the timer method.

 private void timer1_Tick(object sender, EventArgs e)
    {
                   Bitmap bitmap2 = new Bitmap(640, 480,PixelFormat.Format8bppIndexed);

        ColorPalette palette = bitmap2.Palette;

        for (int i = 0; i < 256; i += 3)
        {
            Color b = new Color(); 
            b = Color.FromArgb(i);
            bitmap2.Palette.Entries.SetValue(b, i);
           //b = Color.FromArgb(palette[i], palette[i + 1], palette[i + 2]);
           // bitmap.Palette.Entries.SetValue(b, i);
            //bitmap.Palette = palette;
        } 

        mandelbrot();
    }

The original image is called bitmap and the palette needs to be bitmap2.
Thanks

Answer 1

ColorPalette palette = originalBitmap.Palette;
Color first = palette.Entries[0];
for (int i = 0; i < (palette.Entries.Length - 1); i++)
{
    palette.Entries[i] = palette.Entries[i + 1];
}
palette.Entries[(palette.Entries.Length - 1)] = first;
originalBitmap.Palette = palette;