How to move a certain part of a picture box using Visual Studio c#

Question

I would like to only move a certain part of my picture box however I could move only that certain part. Currently I can move it from left to right but I only want to move the tip of it only.

    private float angle = 0.0f;
    Image image;

    private void Form1_KeyDown(object sender, KeyEventArgs e)
    {
        if (e.KeyCode == Keys.Right) angle += 1;
        else if (e.KeyCode == Keys.Left) angle -= 1;

        int a = pictureBox1.Location.X;
        int b = pictureBox1.Location.Y;

        if (e.KeyCode == Keys.Right) a += 5;
        else if (e.KeyCode == Keys.Left) a -= 5;

        pictureBox2.Location = new Point(a, b);

        RotateImage(pictureBox1, image, angle);
    }

    private void RotateImage(PictureBox pb, Image img, float angle)
    {
        //Store our old image so we can delete it
        Image oldImage = pb.Image;
        pb.Image = RotateImage(img, angle);

        if (oldImage != null)
            oldImage.Dispose();
    }

    public static Bitmap RotateImage(Image image, float angle)
    {
        return RotateImageFinal(image, new PointF((float)image.Width / 2, (float)image.Height / 2), angle);
    }

    public static Bitmap RotateImageFinal(Image image, PointF offset, float angle)
    {
        //create a new empty bitmap to hold rotated image
        Bitmap rotatedBmp = new Bitmap(image.Width, image.Height);
        rotatedBmp.SetResolution(image.HorizontalResolution, image.VerticalResolution);

        //make a graphics object from the empty bitmap
        Graphics g = Graphics.FromImage(rotatedBmp);

        //Put the rotation point in the center of the image
        g.TranslateTransform(offset.X, offset.Y);

        //rotate the image
        g.RotateTransform(angle);

        //move the image back
        g.TranslateTransform(-offset.X, -offset.Y);

        //draw passed in image onto graphics object
        g.DrawImage(image, new PointF(0, 0));

        return rotatedBmp;
    }

    private void Form1_Load(object sender, EventArgs e)
    {   //Just to store the address of the 'arrow' image.
        string path = Directory.GetCurrentDirectory();
        image = new Bitmap(path + "/img/arrow.bmp");
    } 

A PS of the object that I want to tilt, I'm interested in fixating the bottom part meanwhile only moving the top http://imgur.com/H2ic2g7

Answer 1

I was really interested in your question and so I decided to spend some time to search more about image rotation in C#. So here goes the result.

    private float angle = 0.0f;
    Image image;

    private void Form1_KeyDown(object sender, KeyEventArgs e)
    {
        if (e.KeyCode == Keys.Right) angle+=1;
        else if (e.KeyCode == Keys.Left) angle-=1;

        int a = ballPB.Location.X;
        int b = ballPB.Location.Y;

        if (e.KeyCode == Keys.Right) a += 5;
        else if (e.KeyCode == Keys.Left) a -= 5;

        ballPB.Location = new Point(a, b);

        RotateImage(arrowPB, image, angle);
    }

    private void RotateImage(PictureBox pb, Image img, float angle)
    {
        //Store our old image so we can delete it
        Image oldImage = pb.Image;
        pb.Image = RotateImage(img, angle);

        if (oldImage != null)
            oldImage.Dispose();
    }

    public static Bitmap RotateImage(Image image, float angle)
    {
        return RotateImageFinal(image, new PointF((float)image.Width / 2, (float)image.Height / 2), angle);
    }

    public static Bitmap RotateImageFinal(Image image, PointF offset, float angle)
    {
        //create a new empty bitmap to hold rotated image
        Bitmap rotatedBmp = new Bitmap(image.Width, image.Height);
        rotatedBmp.SetResolution(image.HorizontalResolution, image.VerticalResolution);

        //make a graphics object from the empty bitmap
        Graphics g = Graphics.FromImage(rotatedBmp);

        //Put the rotation point in the center of the image
        g.TranslateTransform(offset.X, offset.Y);

        //rotate the image
        g.RotateTransform(angle);

        //move the image back
        g.TranslateTransform(-offset.X, -offset.Y);

        //draw passed in image onto graphics object
        g.DrawImage(image, new PointF(0, 0));

        return rotatedBmp;
    }

    private void Form1_Load(object sender, EventArgs e)
    {   //Just to store the address of the 'arrow' image.
        string path = Directory.GetCurrentDirectory();
        image = new Bitmap(path + "\\img\\arrow.png");
    }

The credits for the logic goes to MusicMonkey5555 ( http://www.codeproject.com/Articles/58815/C-Image-PictureBox-Rotations ). You can even download the source code from the link in case the above code isn't really clear. Good luck!