Extension method on Bitmap for creating a mirrored (tile) image

I needed a tiled background for something I was working on and decided to revisit my mirror program. I’ve lost the source code to my original program from 2005, but it wasn’t too hard to rewrite it.

I decided to implement this one as an extension method on the Bitmap class. Here is the code for the extension:

namespace MirrorMirror 
{ 
    public static class Utilities { 
        public static Bitmap CreateMirrorImage(this Bitmap srcImage) 
        {
            int dblWidth = srcImage.Width * 2;
            int dblHeight = srcImage.Height * 2; // create an image 2 times the size of the original
            Bitmap newImage = new Bitmap(dblWidth, dblHeight);
            using (Graphics canvas = Graphics.FromImage(newImage)) 
            { 
                // place the original image in the top left corner             
                canvas.DrawImage(srcImage, new Point { X = 0, Y = 0 });

                // rotate and flip the image to create a mirror
                srcImage.RotateFlip(RotateFlipType.RotateNoneFlipX);
                canvas.DrawImage(srcImage, new Point { X = srcImage.Width, Y = 0 });
                srcImage.RotateFlip(RotateFlipType.Rotate180FlipNone);
                canvas.DrawImage(srcImage, new Point { X = 0, Y = srcImage.Height});
                srcImage.RotateFlip(RotateFlipType.RotateNoneFlipX);
                canvas.DrawImage(srcImage, new Point { X = srcImage.Width, Y = srcImage.Height });
                canvas.Save(); 
            } 
            return newImage; 
        } 
    } 
}

To use this code, simply do the following:

openFileDialog1.ShowDialog();
Bitmap srcImage = new Bitmap(openFileDialog1.FileName);
pictureBox1.Image = srcImage.CreateMirrorImage();

As you can see, you’ll need a picture box and an open file dialog on the form for the sample code to work.

This is much simpler than my original program. Here are a few samples of what you can create using it…

Here is the original image:

Here is the first pass of the tile:

And the second pass of the tile: