Thread: Basic image rotation method

Hey everyone, i am new here and to java. I am currently just starting to learn java and have a problem trying to figure out a simple method. I am writing methods to rotate images, i can do left and right, but cannot make it rotate 180 degree's. I thought it would be as easy as copying and pasting a few lines or multiplying some of the ints from one of my other methods(bottom method is from my rotate right method), any advice or suggestions?

Thanks

  public void copyPictureLeftRotation(Picture sourcePic)
{
  Picture targetPicture = this;
  Pixel sourcePixel = null;
  Pixel targetPixel = null;
  int targetX, targetY = 0;
  int width = sourcePic.getWidth();
  int height = sourcePic.getHeight();
// loop through the rows
  for (int sourceX = 0; sourceX < width; sourceX++)
  {
// loop through the colomns
    for (int sourceY = 0; sourceY < height; sourceY++)
    {
// set the target pixel color to the source pixel color
      sourcePixel = sourcePic.getPixel(sourceX,sourceY);
      targetX = sourceY;
      targetY = width - 1 - sourceX;
      targetPixel = targetPicture.getPixel(targetX,targetY);
      targetPixel.setColor(sourcePixel.getColor());
    }
 
  }
}

You can easily rotate a picture using an affine transformation (built into the standard JDK). Note that you'll have to take into account the fact that rotating the image at a non-right angle multiple will need a larger resultant image to fit the axis-aligned bounding box.

// angle is specified in radians, angle is measured from positive x axis
// I'm pretty sure this will work, I didn't actually try it
public BufferedImage rotateImage(BufferedImage original, double angle)
{
    BufferedImage result = new BufferedImage((int)(original.getWidth() * Math.abs(Math.cos(angle))), (int)(original.getHeight() * Math.abs(Math.sin(angle))));
    Graphics2D g = result.createGraphics();
    AffineTransform transform = new AffineTransform();
    transform.rotate(angle);
    g.drawImage(original, transform, null);
    return result;
}